|Year : 2017 | Volume
| Issue : 5 | Page : 33-64
|Date of Web Publication||4-Dec-2017|
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
. Poster Presentation. Indian J Nucl Med 2017;32, Suppl S1:33-64
| Clinical Nuclear Medicine|| |
| PP 1:083058|| |
Relationship between regional gastric emptying (proximal and distal stomach) with total gastric emptying in patients with dyspepsia
Arpana Arbind, Shwetal Pawar, Suruchi Shetye, Mangala Ghorpade
Department of Nuclear Medicine and PET Imaging, Seth S. G. Medical College and KEM Hospital, Mumbai, Maharashtra, India
Rationale: The fundus (proximal stomach) acts for accommodation and antrum (distal stomach) contraction cause grinding and trituration. The purpose of the study was to find out if these areas individually affected total gastric emptying. Materials and Methods: A total of 28 patients with dyspepsia(19 men and 9 women of median age 42 years and 8 control) were given solid meal (4 idlis with 5 g butter; calories – 284 kcal, proteins – 8.2 g, carbohydrates 53.9 g, fats 6.4 g) labeled with 99mTc-sulfur colloid. Anterior, posterior serial images of the abdomen taken at 1, 5, 15, 30, 45, 60, and 120 min using Dual head gamma camera mounted with LEHR collimator. Region of interest (ROI) over the whole stomach, proximal and distal compartments were drawn. Total, proximal, and distal gastric retention (%) at 1 and 2 h and linear fit T½ (min) were calculated. A P< 0.05 was considered statistically significant. Result: Out of 28 patients, 18 patients showed delayed total gastric emptying, 17 (60.7%) showed delayed proximal, and 21 (75%) showed delayed distal gastric emptying at 2 h. There was a significant difference (P < 0.05) found in retention of cases and control at 2 h in all total, proximal, and distal; however, there was no significant difference (P = 0.39) in proximal and distal stomach retention at 2 h in cases. Conclusion: Process of accommodation of proximal stomach or the contraction of antrum (distal stomach) does not individually affect the total gastric emptying.
| PP 2:093008|| |
Comparison of 18F-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography and 131-I-metaiodobenzylguanidine in paraganglioma and pheochromocytoma
Priyanka Verma, Sunita Sonavane, Gaurav Malhotra, Ankita Tiwari1, Anurag Leela, Tushar Bandgar, Ramesh V. Asopa, Nalini S. Shah1
Radiation Medicine Centre, Bhabha Atomic Research Centre, 1Department of Endocrinology, King Edward Memorial Hospital, Mumbai, Maharashtra, India
Rationale: Pheochromocytoma (PCC) and paraganglioma (PGL) are rare chromaffin cell tumors that are born to be imaged by functional imaging even though anatomical imaging (computed tomography [CT]/magnetic resonance imaging) aid in their precise localization. Studies comparing glucose transporter expression (18F-fluoro-2-deoxy-D-glucose [18-F FDG]) and 131-metaiodobenzylguanidine (MIBG) uptake in these tumors are lacking. Methodology: This is a retrospective study of 22 patients (10 male, 12 female; age range 14–66 years; mean age: 39 years) of proven or suspected PGL/PCC who underwent both 131 MIBG scan and 18-F FDG positron emission tomography (PET)/CT within 15 days' time interval between the two studies in the last 1 year, as per the institution protocol. Correlative anatomic imaging, postoperative histopathology, and follow-up evaluation were utilized to arrive at the final diagnosis. PET/CT images were evaluated qualitatively and semi-quantitatively. Lesion-based sensitivities were compared between FDG and MIBG scans. Key Results: Of 22 patients, 16 patients showed 22 positive lesions on either scan (17 primary, 1 pancreatic neuroendocrine tumor [NET], 3 nodal, and 1 vertebral metastases). MIBG and FDG both detected true primary tumors. However, lesion-based sensitivity was higher for FDG than MIBG (100% [22/22] and 81.8% [18/22], respectively). Maximum standardized uptake value for the lesions ranged from 5 to 17 (median: 7.03). 131-I MIBG showed false negative in small-sized nodal metastases and pancreatic NET. There was also 1 false positive with MIBG which was due to infective changes in the lungs. Six patients were found to have no PCC or PGL on close follow-up (true negative), and both imaging modalities were negative in these patients. Research Highlights: MIBG and FDG PET/CT detected the primary tumors accurately. F-18 FDG PET/CT detected more number of lesions compared to MIBG. The performance of PET/CT is superior to that of MIBG scintigraphy in patients with PCC/PGL, mainly for familial, extra-adrenal, and metastatic diseases. However, MIBG remains important in selected clinical contexts and selecting patients suitable for 131-I-MIBG therapy.
| PP 3:192928|| |
Radioactive iodine 131 therapy in a case of carcinoma thyroid with distant metastases on initial presentation in a serving soldier of Indian army
Army Hospital R and R, New Delhi, India
Rationale: The objective is to study the role of radioactive iodine treatment in a case of thyroid carcinoma with distant metastases in a case of serving soldier of Indian army who initially presented with a sacral mass which on evaluation was found as distant metastases of thyroid carcinoma. Methodology: High-dose radioactive iodine therapy was given to a serving soldier who presented with an initial presentation of a sacral mass and brain metastasis and later on evaluation was diagnosed as a case of thyroid carcinoma. Posttherapy, the serving army soldier, clinically improved very significantly. Results: High-dose radioactive iodine therapy was very effective in patient of thyroid carcinoma with distant metastases at initial presentation. Research Highlights: This case of a serving soldier with inoperable distant metastases at presentation from thyroid carcinoma was well treated with high dose radio-iodine therapy.
| PP 4:185038|| |
Outlook of newly inducted residents toward radiation specialties: Nuclear medicine, radiation oncology, and radiology
Sanchay Jain, Ashok Kumar, Vandana Kumar Dhingra
All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India
Rationale: As a relatively unknown subject at undergraduate level, we felt the need to assess the outlook of new postgraduate entrants toward the radiation specialties 2 months since joining their course is and analyze it from their perspective. Methodology: Questionnaires related to perception of their specialty were filled by new postgraduate entrants in the radiation specialties. Replies were either in choices of “Yes” or “No.” Category I included questions based on knowledge about their specialty before choosing it, Category II included questions based on satisfaction regarding their specialty, and Category III was related to concerns about radiation exposure. Key Results: Out of 11 respondents, 72.7% were male. 33.4%, 49.1%, and 52.7% respondents replied affirmatively or as “Yes” in Category I, II, and III, respectively. Research Highlights: More males chose radiation specialties. Majority of candidates had no prior knowledge about their field. At 2 months since joining, nearly half of the candidates were satisfied with their chosen field but had concerns about radiation exposure. Concerns about radiation exposure should be dealt with by ensuring early training on safe radiation practices. We incorporated integrated teaching to address this issue. Increasing exposure to radiation specialties during undergraduate level can further improve informed decision-making and thus student outcomes professionally and psychologically.
| PP 5:232726|| |
Comparison of single-sample and two-sample methods of glomerular filtration rate measurement using technetium-99m diethylene triaminepentaacetic acid in pediatric patients
Jyoti Mishra, R. Gopinath, H. Dhanapathi, Nandini Pandit, Madhusudhanan Ponnusamy
Department of Nuclear Medicine, JIPMER, Puducherry, India
Introduction: Glomerular filtration rate (GFR) is a very sensitive measure of kidney function. It is helpful in assessing the progression of disease and planning timely intervention in chronic kidney injury patients, for assessing global renal function in patients receiving nephrotoxic chemotherapeutic agents and also in voluntary kidney donors. Russell's two-sample slope-intercept method (measured GFR [mGFR]) using technetium-99m (Tc-99m) diethylene-triamine-pentaacetate acid (DTPA) is one of the novel methods for measuring GFR. However, this method requires bolus injection of tracer, followed by collection of venous blood samples at 60 and 180 min, which is cumbersome in pediatric patients. Hence, we have compared the effectiveness of single sample methods with mGFR. Aim: To estimate the correlation between mGFR and Russell's single sample (GFR[R]) and Fleming's single sample (GFR[F]) methods of GFR calculation. Materials and Methods: We retrospectively evaluated GFR measurements from pediatric patients referred to the Department of Nuclear Me dicine between January 2015 and October 2016. Patients were administered bolus intravenous injection of Tc-99m DTPA injection; venous blood samples were collected after 1 h and 3 h. mGFR was calculated and normalized to body surface area (BSA). Three-hour plasma sample values were only used for calculating GFR[R] and GFR[F]. Data were entered and analyzed in Microsoft Excel 2007. After checking normality, Pearson's correlation was done. Bland–Altman analysis was done to assess the average bias and agreement. Results: A total of 101 subjects who underwent GFR measurement were included for analysis. GFR[R] for 73 subjects turned up to be uninterpretable. They were excluded from analysis. No such data were noted for GFR[F]. Mean age of patients was 4.04 years (standard deviation [SD] 3.6). Mean mGFR value was 68.01 ml/min/1.73 sq. m BSA (SD - 35.34). Mean GFR[R] value was 78.75 ml/min/1.73 sq. m BSA (SD - 34.33). Mean GFR[F] value was 85ml/min/1.73 sq. m BSA (SD - 35.2). Pearson's correlation for mGFR and GFR[F] was 0.538 (strong correlation) and for GFR[R] and mGFR was 0.151 (poor correlation). Bland–Altman analysis showed mean bias of 17.31 for mGFR and GFR[F] and 5.809 for GFR[R] and mGFR. Although the mean bias between GFR[R] and mGFR was 5.809, the values are scattered far from the line of equality. Conclusion: Strong correlation was seen between mGFR and GFR[F], but bias was significant. Poor correlation was seen between mGFR and GFR[R]. Although bias was minimal compared to GFR[F], points were scattered from line of equality stating poor agreement. Compared to Russell's single-sample method, Fleming method is better for GFR calculation.
| PP 6:230853|| |
Prevalence of skeletal metastasis in patient with prostate cancer with different prostate-sensitive antigen levels
Farheen, Satyawati Deswal, Dhananjay Kumar Singh, Shaswat Verma
Dr. Ram Manohar Lohiya Institute of Medical Sciences, Lucknow, Uttar Pradesh, India
Rationale: Bone scintigraphy is the best diagnostic choice for detection of skeletal metastasis in prostate cancer; nowadays, a well-known tumor markers serum for prostate cancer is available that is prostate sensitive antigen (PSA); in this study, we determine the utility of PSA for predicting the presence of skeletal metastasis with different PSA levels to avoid unnecessary investigation and to avoid physical burden on patient. Methodology: A retrospective study was performed on 150 consecutive prostate cancer patients with age group 40–80 years, who had undergone through bone scintigraphy and also evaluated the serum PSA. Result: Bone scan was found to be positive in 90 patients and negative in 60 patients; of positive cases, 90% had serum PSA >100 ng/ml and 10% had PSA 20–100 ng/ml; all the patients with PSA >00 ng/ml have multiple metastasis; in negative bone scan patients, 95% had PSA <20 ng/ml and remaining 5% had 20–80 ng/ml. Research Highlights: With the higher level of serum PSA, the probability of multiple skeletal metastases is higher.
| PP 7:225938|| |
Comparison of glomerular filtration rate estimated by the technetium-99m diethylene-triamine-pentaacetic acid and that from from effective renal plasma flow with technetium-99m-ethylenedicysteine in voluntary kidney donor patients
Chandra Shekher Kumar, Satyawati Deswal, Dhananjay Kumar Singh
Dr. RMLIMS, Lucknow, Uttar Pradesh, India
Rationale: The study was to compare glomerular filtration rate (GFR) estimated by the technetium-99m diethylene-triamine-pentaacetate acid (99mTc DTPA) and calculated effective renal plasma flow (ERPF) with 99mTc-ethylenedicysteine (EC) in voluntary kidney donor patients. Methodology: This study group comprised of 15 patients, out of which were 8 male and 7 female (age range 25–55 years). The estimated GFR by the 99mTc DTPA and 99mTc-EC and each of both compare with the gold standard technique of 24 h of urine creatinine clearance. Categorical variable shall be compared using Chi-square test. Continuous variable shall be compared using t-tests or ANOVA. Key Result: GFR calculated from ERPF value obtained with 99mTc-EC correlated well with an estimated by 99mTc DTPA in voluntary kidney donor patients (i.e., at normal serum creatinine level). Research Highlight: Calculation of GFR from ERPF value with the help of 99mTc-EC can be reliable and alternative of 99mTc-DTPA method in voluntary kidney donor patients.
| PP 8:225708|| |
Effect of region of interest on glomerular filtration rate estimated by camera-based Gates method at various serum creatinine level
Dheeraj Kumar Pandey, Satyawati Deshwal, Dhananjay Kumar Singh, Shashwat Verma
Department of Nuclear Medicine, Dr. Ram Manohar Lohia Institute of Medical Sciences, Lucknow, Uttar Pradesh, India
Rationale: The study was to estimate glomerular filtration rate (GFR) by drawing circular background region of interest (ROI) and compare it with elliptical background ROI and correlate with the various serum (sr.) creatinine levels using Gates formula. Methodology: Three groups of patients are taken: Group 1 - sr. creatinine value between 0 mg/dl and 1 mg/dl; Group 2 - sr. creatinine value between 1 mg/dl and 2 mg/dl; and Group 3 - sr. creatinine value above 2. GFR is calculated by drawing circular background ROI using Gates formulae, values of GFR are compared with GFR calculated by elliptical background ROI, results are then correlated with various sr. creatinine value groups, and Modification of Diet in Renal Disease (MDRD) values are also determined. Key Results: It is seen that patients with higher sr. creatinine value GFR with circular background ROI correlates well with MDRD formulae. The study suggests circular background ROI for GFR calculation in higher creatinine value using camera-based Gates formulae.
| PP 9:200323|| |
Comparison of estimated glomerular filtration rate equations with measured glomerular filtration rate in pediatric patients with chronic kidney injury
R. Vishnukumar, R. Gopinath, Madhusudhanan Ponnusamy, H. Dhanapathi, Nandini Pandit
Department of Nuclear Medicine, JIPMER, Puducherry, India
Introduction: Technetium-99m diethylene-triamine-pentaacetate acid (Tc-99m DTPA) plasma clearance technique is considered reference radionuclidic method of GFR measurement. Various GFR equations are employed in clinical practice for estimating GFR. However, validity of these equations in predicting the most appropriate value varies with equations, age group, etc. In this study, we compared GFR estimated using Schwartz1976 (eGFR [O]) and updated Schwartz equations (eGFR [N]) with Russell's two-sample slope-intercept method (measured GFR [mGFR]). Aims and Objectives: To estimate the correlation between Russell's two-sample slope-intercept method, Schwartz1976 (eGFR [O]), and updated Schwartz (eGFR [N]) equations in pediatric chronic kidney injury patients. Materials and Methods: We retrospectively evaluated GFR measurements (mGFR) carried out among pediatric patients with chronic kidney injury referred to our department between April 2015 and August 2017. GFR measurements were done by bolus intravenous injection Tc-99m DTPA, two venous blood samples were collected at 60 and 180 min postinjection. GFR values were normalized to body surface area (BSA). Serum (S.) creatinine values were measured using Modified Jaffe's method. S. creatinine values measured within 8 weeks of GFR measurement were included. eGFR [O] and eGFR [N] were calculated by using S. creatinine values and height measured in meters. Data were analyzed using IBM SPSS version 21.0. After checking normality, Pearson's correlation was applied. mGFR calculated by Russell's two-sample slope-intercept method was kept as reference GFR. Bland–Altman plot analysis was performed to evaluate the bias between the mean differences of both the estimated GFR methods with reference method (Russell's method). Results: A total of 85 cases were analyzed. Mean age was 4.2 years (standard deviation [SD]-3.9 years). Mean S. creatinine values were 0.9 mg/dl (SD-0.72 mg/dl). Mean mGFR was 68.08 ml/min/1.73 sq. m BSA (SD-28.15), mean eGFR [O]was 86.97ml/min/1.73 sq. m BSA (SD-34.86), and mean eGFR [N] was 51.3 ml/min/1.73 sq. m BSA (SD-20.56). Pearson's correlation coefficient for both mGFR–eGFR [O] and mGFR–eGFR [N] equations was 0.730, showing strong correlation between eGFR [O] values, eGFR [N] values, and mGFR values. Bland–Altman plot analysis of mGFR–eGFR [O] and mGFR–eGFR [N] showed average bias 18.8 ml/min and −16.77, respectively, which are significantly deviated from mGFR values. Conclusion: The study shows good correlation between mGFR and eGFR values obtained by both Schwartz1976 and updated Schwartz equations. However, there was significant bias between eGFR values obtained by both equations and mGFR. This leads to significant error in clinical application.
| PP 10:145033|| |
Evaluation of differential renal function on technetium-99m-dimercaptosuccinic acid and technetium-99m-L, L-ethylenedicysteine in unilateral hydronephrosis: A comparative study
Anukritti Mary Lakra, Madhavi Tripathi, Rajeev Kumar, Minu Bajpai1, Prabhjot Singh2, Prabudh Goel1, Nishikant A. Damle, Chandrasekhar Bal
Departments of Nuclear Medicine, 1Pediatric Surgery and 2Urology, AIIMS, New Delhi, India
Rationale: Differential renal function (DRF) is an important parameter assessed in unilateral hydronephrosis, especially for deciding on the need for surgical intervention. Although this parameter is usually assessed on the renal dynamic study (RDS) with technetium-99m-L, L-ethylenedicysteine (99mTc-LLEC), cortical function can most reliably be assessed on technetium-99m-dimercaptosuccinic acid (99mTc DMSA) scintigraphy. We therefore undertook this study to assess DRF calculated on 99mTc-LLEC versus that on 99mTc DMSA. Methodology: A total of 20 patients with unilateral hydronephrosis, age ranges from 5 to 50 years, underwent both 99mTc DMSA and 99mTc-LLEC scintigraphy within 14 days. Computer-based calculation of DRF was carried out by drawing whole-kidney regions of interest (ROI) and subrenal background ROI. The Wilcoxon paired signed-rank test was used to test for significance of difference between the DRF on 99mTc DMSA and 99mTc LLEC. Key Results: DRF of the hydronephrotic kidney in each patient was compared between the two radiopharmaceuticals. The values of DRF of unilateral hydronephrotic kidney on Tc-99m-LLEC and Tc-99m-DMSA images were 46.0 ± 17.8 and 46.9 ± 17.0, respectively. There were no significant difference between (P = 0.91) the two. Research Highlights: This study suggests that DRF calculated in hydronephrotic kidney s with 99mTc-LLEC and 99mTc DMSA is comparable. Thus, DRF on 99mTc-LLEC RDS can be reliably used for preoperative evaluation and follow-up of hydronephrotic kidneys.
| PP 11:144225|| |
A pilot study to assess the role of early dynamic positron emission tomography/computed tomography with 18F-fluoro-choline in imaging of parathyroid adenomas
Garima Kumari, Meghana Prabhu1, Nishikant Avinash Damle1, Madhavi Tripathi1, Chandrasekhar Bal1, Praveen Kumar1, Rajeev Kumar1, Ravi Kant Gupta1, Rajesh Khadgawat2, K. Devasenathipathy3
Departments of 1Nuclear Medicine, 2Endocrinology and 3Radiodiagnosis, AIIMS, New Delhi, India
Rationale: To assess the utility of early dynamic positron emission tomography/computed tomography (PET/CT) with 18F-fluoro-choline (FCH PET/CT) in imaging of parathyroid adenomas and to generate tracer kinetic parameters. Methodology: In this prospective study, five patients with biochemical evidence of primary hyperparathyroidism and positive technetium-99m (99mTc)-Sestamibi scan have been included till date. Dynamic FCH PET/CT images were taken after injection of 5–8 mCi (185–296 MBq) from angle of mandible to heart, at 1 min per frame for 15 min. Then, static images of 2–3 min per bed position were taken between 45 and 60 min. Three-dimensional regions of interest were plotted on known parathyroid adenoma, cervical lymph node, and thyroid. Dynamic and static images were interpreted by two expert nuclear medicine physicians independently, and the following parameters were calculated for parathyroid adenoma and cervical lymph node - maximum standardized uptake value (SUVmax), time-activity curve for SUVmax, tpeak. Then, adenoma to thyroid ratio and cervical lymph node to thyroid ratio were calculated for each dynamic and static image. Key Results: Five patients were included (4 females and 1 male; 4 adults and 1 child). Median age of the study group is 36 years. Mean serum parathyroid hormone level was 134.8 pg/mL and mean serum calcium level was 11.4 mg/dL. All patients showed a higher SUVmax for adenomas and cervical lymph nodes in dynamic images as compared to static images. Mean difference in SUVmax between dynamic and static images in adenoma was 70.6% and in cervical lymph node was 55.4%. Mann–Whitney U-test was used to compare the ratios obtained. It revealed no significant difference between dynamic and static adenoma/thyroid uptake ratio but showed a significant difference between uptake in the adenomas as compared to lymph nodes. Time to peak SUVmax in adenoma was seen within first 6 min in all patients while it was after 6 min in the lymph nodes. Research Highlights: Significant difference in SUVmax between adenomas and nodes was seen on both dynamic and static images. Furthermore, early dynamic imaging could suffice, without the need for a delayed image. This technique of FCH PET could adequately differentiate a parathyroid adenoma from a cervical lymph node. This is a pilot study with a small group. We intend to continue the study on a larger scale and review the results.
| PP 12:121404|| |
Dacryoscintigraphy by pediatric dropper technique: A user-friendly instillation procedure
Anurag Jain, Deepak Aheer, Braj Kishore, Arun R. John
Army Hospital R and R, Delhi Cantt, India
Rationale: Instillation or application of the radiotracer over the tear film is one of the important parts of dacryoscintigraphy. Our study explains the value of an improvised dropper technique so that desired amount of radioactivity in desired volume can be instilled over the tear film. The aim of the study is to introduce a simple and convenient instillation method based on dropper technique for performing dacryoscintigraphy. This improvised dropper technique can be used so that desired amount of radioactivity in desired volume can be instilled over the tear film. The objectives of this experiment are to measure the volume and activity of each drop from the dropper. Methodology: Experiment of volume and activity measurement standardization was carried out in two parts. In the first part, we calculated volume of each drop indirectly to standardize the volume of drop. In the second part, we standardized the activity in each drop by measuring it in a dose calibrator. In this study, we used a common pediatric dropper of approximately 1 ml capacity, radioactivity (99mTcO4 – pertechnetate), sample vial (container), vial holder, a pair of nonsterile gloves, dose calibrator, etc. Experiments of volume and radioactivity standardization were carried out in two parts. The first part of experiment calculated volume of each drop indirectly, and in second, we standardized the activity in each drop by measuring it in dose calibrator. Statistical Analysis Used: ANOVA test was used to calculate the correlation of readings by same individual as well as among the three individuals. Key Results: After analysis of result obtained, it was understood that there was no significant difference found in volume and activity of each drop in the readings recorded by the same individual as well as among the three individuals. The calculated activity and observed activity were 86.64 μCi and 79.16 μCi, respectively. The difference was only 8.63% lying within acceptable limits. Research Highlights: The aim of the study is to introduce a simple and convenient instillation method based on dropper technique for performing dacryoscintigraphy. This improvised dropper technique can be used so that desired amount of radioactivity in desired volume can be instilled over the tear film. The objectives of this experiment are to measure the volume and activity of each drop from the dropper.
| PP 13:110852|| |
Symptom profile of patients in the nuclear medicine thyroid clinic
Ashok Kumar, Sanchay Jain, Vandana Kumar Dhingra
All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India
Rationale: Nuclear medicine thyroid clinic was started recently at our institute. We observed a pattern of symptoms among the initial patients and this led us to study and analyze the common presenting symptoms in patients with thyroid disorders. Methodology: This was an observational cross-sectional study of the symptoms of initial patients attending the nuclear medicine thyroid clinic. We evaluated the symptoms and correlated them with their diagnoses. Key Results: Total number of patients was 78 with 70 females. Of the various symptoms observed, the most common were musculoskeletal (myalgia, fatigue, joint pain), constitutional (heat/cold intolerance, appetite changes, and fever), chest (breathlessness and chest discomfort), and menstrual (oligomenorrhea and menorrhagia), which were found to be in the frequency of 48.71%, 76.92%, 38.46%, and 22.85%, respectively. Symptoms were seen to occur more commonly in hypothyroid patients, i.e., 63.33%, 73.69%, 61.53%, and 87.5%, respectively. There was overlap in symptomatology among both the hypothyroid and hyperthyroid patients with regard to musculoskeletal and constitutional symptoms. Research Highlights: Overall symptomatology of hypothyroid or hyperthyroid patients showed considerable overlap with musculoskeletal and constitutional symptoms as the most common complaints in patients coming to a nuclear medicine thyroid clinic. A larger study of detailed symptomatology is required.
| PP 14:194903|| |
To validate the radiolabeled idli (savory cake) as an ideal alternate vegetarian meal in comparison with routinely used other meals for gastric emptying scintigraphy for solids
Prathamesh Rajai, Natasha Singh, Amit Abhyankar
Department of Nuclear Medicine and PET-CT, P. D. Hinduja National Hospital and MRC, Mumbai, Maharashtra, India
Rationale: To validate an ideal vegetarian well uniformly radiolabeled solid meal for gastric emptying scintigraphy (GES), which is easily fully consumed by patients in view of their common symptoms in such indications, and in keeping with Indian food culture. Methodology: Following various types of solid meal preparations were labeled with 1 mCi of technetium-99m (99mTc) sulfur colloid and image of each meal was acquired on GE Infinia Hawkeye 4 camera. (1) Meal of four slice bread + 20 g butter with calorific value ≈ 356 kcal. (2) Four slice bread + 30 g jam with calorific value ≈ 332 kcal. (3) Four slice bread + 70 ml of milk with calorific value ≈ 243 kcal. (4) 150 g of sagu (sabudana) + 5 ml refined vegetable oil + 10 g peanuts (sagu kichadi) with calorific value ≈ 324 kcal. (5) Four idlis + 2 tablespoons green chutney with calorific value ≈ 280 kcal. (6) 70 g wheat +50 ml water + 5 ml refined vegetable oil with calorific value ≈ 237 kcal. (7) Meal of 75 g of idli mix + 80 ml water + 10 g butter with calorific value ≈ 310 kcal. Key Result: Idli meal prepared with radiotracer added to batter mixture itself, with calorific value ≈ 310 kcal, showed highest uniform Tc99m sulfur colloid distribution in comparison to all other meal preparations. Research Highlights: Radiolabeled idli (savory cake) prepared with radiotracer added to the batter mixture itself appears to be ideal vegetarian meal in comparison to all other meal preparations, for GES studies, especially among patients with specific dietary restrictions.
| Cardiology|| |
| PP 15:222706|| |
Evaluation of distinctly variable myocardial uptake of 68Ga-DOTATATE in neuroendocrine tumor patients undergoing 177Lu therapy
Sutapa Rakshit, Basant L. Malpani, Sunita Sonawane, Nawab Singh Baghel, Sandip Basu, Sharmila Banerjee
Radiation Medicine Centre, BARC, Mumbai, Maharashtra, India
Introduction: Neuroendocrine tumors (NETs) have distinct biological and clinical characteristics. Role of noble PET tracer 68Ga-DOTATATE to detect NET has already been established. It is reported that 68Ga-DOTATATE as an efficacious marker of atherosclerotic inflammation with excellent macrophage specificity and better uptake property to discriminate high-risk versus low-risk coronary lesions. Patients undergoing 68Ga-DOTATATE scan for evaluation of various neural crest tumors, pre- and post-177Lu therapy were randomly selected to observe myocardium uptake. Mean standardized uptake value (SUVmean)/maximum SUV (SUVmax) is a useful measure for characterizing benign versus malignant lesions which is used to calculate variable uptake in myocardium. Aims and Objectives: To evaluate variable myocardial uptake in NET patients undergoing 177Lu therapy and compare with lung uptake as background. Materials, Methods, and Patients: Whole-body positron emission tomography-computed tomography (PET-CT) scans were acquired in 32 patients at about 1 h postinjection of 2–3 mCi of 68Ga-DOTATATE in 16 slice PHILIPS time-of-flight PET-CT scanner. Both visual analysis and quantitative analysis were performed to identify the nature of uptake and its distribution. Region of interest was drawn on myocardium and apical region of lung in coronal slices of the reconstructed images. Average SUV and SUVmax were noted for each region. Heart-to-lung (H/L) ratio was calculated to understand variable uptake pattern in visually normal and abnormal myocardium. Results: Most of the patients selected in this study group had received 177Lu-DOTATATE therapy in one or more sittings. Based on the visual interpretation of the image and age of patients, the myocardial uptake of the study population was graded as normal, uniform, patchy myocardium and patchy aorta to understand the nature of the uptake. Six young patients (age 17–25 years) with no anticipated myocardial disease were selected to serve as normal controls. The average H/L ratio was noted as 1.82, 0.19 (mean, standard deviation [SD]). Thirteen patients showed uniformly increased myocardial uptake 4.46, 1.37 (mean, SD); five patients showed patchy myocardial uptake 3.10, 1.60 (mean, SD); whereas eight patients had patchy aortic uptake 2.25, 0.73 (mean, SD). Conclusions: This study shows distinctly variable myocardial uptake in NET patients undergoing 177Lu therapy. The reason for increased myocardial uptake cannot be assessed without correlative evidences. Since, 68Ga-DOTATATE is reported to be excellent marker for atherosclerotic inflammations, prospective evaluation of cardiac uptake in a selected group of patients with coronary artery disease will provide more useful information.
| PP 16:141102|| |
Analysis of risk factors for coronary artery disease in patients undergoing screening with myocardial perfusion imaging: A preliminary analysis
Suneel Kumar Malipedda, Ankur Pruthi, Promila Pankaj, Ritu Verma, Ethel S. Belho, Harsh Mahajan
Department of Nuclear Medicine and PET CT, Mahajan Imaging, Sir Ganga Ram Hospital, New Delhi, India
Background: The study aimed to evaluate the distribution of various risk factors in patient population undergoing technetium-99m (Tc 99m) sestamibi myocardial perfusion imaging for screening of coronary artery disease. Methodology: A total of 30 patients (22 males, 8 females; mean age 50.2 ± 11.9 years; range 47–75 years) who underwent 99m Tc sestamibi myocardial perfusion imaging in our department between June 1, 2017, and September 26, 2017, were prospectively analyzed. The presence of various risk factors such as diabetes, hypertension, smoking history, positive family history, obesity (body mass index [BMI]), deranged renal function dyslipidemia, and sedentary lifestyle was analyzed in this population to study its distribution among patients. Appropriate statistical tests were employed to study the significance. Key Results: Out of the total 30 patients, 21 were found to be having significant reversible myocardial ischemia. Out of the 21 patients diagnosed with reversible ischemia, 33% had diabetes mellitus, 66% had hypertension, 33% had smoking history, 55% had positive family history of coronary artery disease, 25% were obese (BMI 30 or more), 16% had deranged renal function, 61.5% had dyslipidemia, and 30% had sedentary lifestyle. Conclusion: In patients, where evidence of reversible ischemia was found, having significantly higher number had risk factors such as hypertension, diabetes, positive family history and dyslipidemia. These are the most important risk factors to predict the occurrence of coronary artery diseases.
| PET-MR/PET-CT/SPECT|| |
| PP 17:235442|| |
Role of fluoro-ethyl-tyrosine positron emission tomography-computed tomography for the detection of noncerebral tumors
Hitesh Aggarwal, Maria D'Souza, Puja Panwar Hazari1, Santosh Pandey, Harish Rawat, Sanjeev Saw, Yachna Solanki, Mita Dutta, Tarakant, Sachin Soni1, Rajnish Sharma, Anil K. Mishra1
Division of Nuclear Medicine and PET Imaging, MIRC, Institute of Nuclear Medicine and Allied Sciences, 1Division of Cyclotron and Radiopharmaceutical Sciences, MIRC, Institute of Nuclear Medicine and Allied Sciences, Delhi, India
Rationale: O-(2-18F-fluoroethyl)-L-tyrosine (18F-FET) positron emission tomography (PET) has shown promising results in brain tumor diagnosis. The aim of this prospective study was to evaluate 18F-FET PET in comparison with 18F-fluorodeoxyglucose (FDG) PET in patients with extracerebral tumors. Methodology: Whole-body FDG and FET scans were done for two patients. One of which was diagnosed as primary lung squamous cell carcinoma with brain metastasis. And, the other is diagnosed as primary breast carcinoma with skull metastasis. The FET and FDG images were compared for both patients. Key Results: Strikingly similar uptake in both FDG and FET scans were noted with FET showing slightly lower SUV max values and higher background distribution, i.e., in muscles. However, FET tumor uptake was found to be more specific for tumor and no increased uptake was noted in inflammatory lymph nodes and bowel loops. Research Highlights: Our preliminary results suggest rather selective uptake of 18F-FET in squamous cell lung and breast carcinomas. In addition, compared with 18F-FDG PET, 18F-FET PET may allow a better distinction between tumors and inflammatory tissues in patients with squamous cell carcinomas. However, it should be kept in mind that the sensitivity of FET PET-CT scan can be low because of lower standard uptake values.
| PP 18:234747|| |
To estimate the normal liver maximum standardized uptake value and mean standardized uptake value in patients who underwent simultaneous positron emission tomography magnetic resonance imaging in our institute
R. Gopinath, S. Dinesh Kumar, Raman Kumar Joshi, Chandana Nagaraj, M. Sandhya, A. K. Gupta
Department of Neuro Imaging and Interventional Radiology, National Institute of Mental Health and Neurosciences, Bengaluru, Karnataka, India
Rationale: To estimate the normal liver maximum standardized uptake value (SUV max) and mean standardized uptake value (SUV mean) in patients who underwent simultaneous positron emission tomography magnetic resonance imaging (PET MRI) in our institute. The results were compared to standard PET-computed tomography (CT) normal liver SUV max and SUV mean. Methodology: Our study was a retrospective analysis of 105 patients (52 male and 53 female) with age ranging from 18 to 77 years who underwent whole-body simultaneous PET MRI (Siemens Biograph mMR) in our institute between January 8th, 2016, and August 16th, 2017. Out of the 105 patients, 12 patients were excluded from this study (due to preexisting liver disease or liver mas detected postscan, extravasation of 18F-fluorodeoxyglucose [F18 FDG] and scans with motion artifacts). Thus, the study included 93 patients (46 males and 47 females) with age ranging from 18–77 years in whom SUV max and SUV mean in normal liver were calculated using the three-dimensional region of interest (3D ROI) method. All of these patients underwent simultaneous PET MRI postintravenous injection of F18 FDG (8–10 mCi). All the whole-body simultaneous PET MRI scans were acquired 60 + 10 min postintravenous injection of F18 FDG. The acquisition parameters were 5–7 beds with image matrix (172 × 172) and images were reconstructed using three iterations with 21 subsets and Gaussian filters. VIBE DIXON sequence was used for attenuation correction for PET. The scans acquired were analyzed and the ROI was drawn in right lobe liver (standard 3D ROI area 10 cm2) and SUV max and SUV mean for normal liver were calculated. Key Results: The 93 patient's scans were analyzed and SUV max and SUV mean in normal liver were calculated using the 3D ROI method. The calculated SUV max for the normal liver uptake is 2.47 ± 0.55 and SUV mean is 1.78 ± 0.77. Research Highlights: In our study, we found that the normal liver uptake following simultaneous PET MRI is comparable to the normal liver uptake following PET CT which is a standardized useful reference parameter in quantitative analysis and also for quantifying therapy response on PET imaging.
| PP 19:115703|| |
Pelvic imaging in positron emission tomography-computed tomography scan
A. Meenakshi, B. Maheshwari, E. R. Radhakrishnan, I. V. Upadhya, F. R. Kingsley, Jephy Joseph, Raghi Jose, Kamaleswaran, Ajit Shinto
Department of Nuclear Medicine and PET CT, Kovai Medical Centre and Hospital, Coimbatore, Tamil Nadu, India
Aim: To delineate the pelvic lesions by pelvic imaging after diuretic administration. Introduction: The pelvic lesions are generally masked because of the radioactive urine in the positron emission tomography (PET) imaging. In this study, the utility of immediate imaging of pelvic region will be evaluated. Materials and Equipment Required: PET scanner, Lasix, 18F-fluorodeoxyglucose (18FDG) were used. Methods: The patient will be administrated with 18FDG; the routine whole-body PET-computed tomography (CT) protocol is followed without the administration of diuretic. The acquisition protocol will be as follows: topogram for pelvic region, CT without contrast, injection of 18FDG PET CT pelvic (2 beds, 2.5 min/bed). Result and Conclusion: As this is a prospective ongoing study, the accumulated results will be presented during the meeting, conclusion drawn thereof.
| PP 20:213049|| |
Positron emission tomography-computed tomography in refractory epilepsy: An institutional experience
Abhishek Mahato, Braj Kishore
Army Hospital Research and Referral, Delhi, India
18F-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG PET CT) is an established modality for evaluation of a case of refractory seizures. By study of the glucose metabolism in brain, it helps in lateralization and localization of epileptogenic foci in presurgical candidates, refractory to medical management. PET-CT is a useful adjunct increasing the detection efficiency along with electroencephalography (EEG) and magnetic resonance imaging (MRI). PET-CT has also been used to evaluate candidates with inconclusive EEG and MRI. Other than localization of seizure focus it also provides additional information on the functional status of the rest of the brain. Methodology: Patients referred for the PET imaging were asked to have early dinner and report on the day of the test empty stomach. The patient were also counseled to avoid tea, coffee, alcohol, sedatives, narcotics, corticosteroids, or other drugs which interfere with brain glucose metabolism. On the day of the investigation, a random blood sugar was taken and scan was carried out only if it was <150 mg/dl. The patients were injected with 18F-FDG according to their body weight (0.14–0.20 mCi/kg) body weight in children and 10 mCi for adults. The patients were asked to relax in the postinjection room which was dimly lit and quiet. The scan begins 30 min after the injection and lasts for 15–20 min. The images were reconstructed by iterative method. A visual semi-quantitative interpretation of the images was carried out. Key Results: Interictal PET images correlated well with the findings of MRI and EEG. In addition, in certain cases, areas of hypometabolism were noted earlier than the MRI. PET-CT also picked up areas of hypometabolism far away from the site of seizure focus – diaschisis. These areas of hypometabolism signified loss of function in a portion of the brain connected to the distant seizure focus. Research Highlights: The series of cases presented by means of poster showcase PET-CT features classical of various spectrum of causes of refractory seizures.
| PET/MR/CT/Neuro-oncology|| |
| PP 21:115205|| |
Role of C-11-methionine positron emission tomography-computed tomography in low-grade astrocytoma
Yachna Solanki, Harish Rawat, Sanjeev Saw, Santosh Pandey, Mita Dutta, Tarakant, Maria D'Souza, Puja Panwar Hazari1, Sachin Soni1, Rajnish Sharma, Anil K. Mishra1
Division of Nuclear Medicine and PET Imaging, MIRC, Institute of Nuclear Medicine and Allied Sciences, 1Division of Cyclotron and Radiopharmaceutical Sciences, MIRC, Institute of Nuclear Medicine and Allied Sciences, Delhi, India
Introduction: (11)C-methionine (MET) is the most popular amino acid tracer used in positron emission tomography (PET) imaging of brain tumors. Because of its characteristics, MET PET provides a high detection rate of brain tumors and good lesion delineation. This study focuses on the role of MET-PET in imaging low-grade astrocytoma. Rationale: PET-CT using 11C-MET has been reported to detect brain tumors with high sensitivity and specificity. In this study, we have evaluated the potential of 11C-MET in recurrent low-grade astrocytoma. Comparison of 18F-fluorodeoxyglucose (F 18-FDG) with 11C-MET has also been done. Methodology: Thirty-three subjects of brain tumor treated by surgery, chemotherapy and or radiotherapy were subjected to [18F]-FDG, [11C]-MET, and magnetic resonance imaging (MRI) scan. The lesions were analyzed semi-quantitatively using tumor to normal contralateral ratio. Diagnosis was confirmed by surgery, stereotactic biopsy, clinical follow-up, MRI, or computed tomography scans. Key Results: Tumor re-recurrence was found in 8 out of 33 patients on [F-18] FDG scan while [11C]-MET was able to detect re-recurrence in 27 out of 33 patients in low-grade astrocytoma. Five of these patients were false positive for presence of re-recurrence of tumor and later found to be harboring necrosis. On semi-quantitative analysis, mean target/nontarget (T/NT) ratio was found to be 2.91 ± 0.91 for lesions positive for recurrence of tumors and 0.71 ± 0.22 for lesions negative for recurrence of tumor on [11C]-MET scan. While the ratio for FDG scan on semi-quantitative analysis was found to be 1.09 ± 0.17 for lesions positive for recurrence of tumors and 0.51 ± 0.15 for lesions negative for recurrence of tumors. Research Highlights: The study highlights that [11C]-MET is superior to [18F]-FDG PET scans to detect recurrence in low-grade astrocytoma. A cutoff value of T/NT value of 1.52 is a useful parameter to distinguish benign from malignant lesion on a [11C]-MET Scan. [11C]-MET scan should be used for evaluation of recurrent low-grade astrocytoma.
| PP 22:140342|| |
Micro-positron emission tomography/computed tomography imaging of in-house synthesized [18F]-based radiopharmaceuticals: An INMAS experience
Ankur Kaul, Puja P. Hazari, A. K. Mishra
Division of Cyclotron and Radiopharmaceutical Sciences, Institute of Nuclear Medicine and Allied Sciences, Delhi, India
Objective: Animal experimentation has been a vital component of exploratory biomedical research. Furthermore, with advancement in computer hardware and software competence, the development of the sophisticated compact whole-body animal imaging system has been facilitated. Methods: We, at INMAS, have a small animal system with an ability to achieve high spatial-resolution and high-sensitivity positron emission tomography (PET) scans with an adequate computed tomography (CT) image quality for anatomic localization and attenuation correction purposes. Besides, this system is also capable of acquiring dual isotope highly sensitive single photon emission computed tomography imaging. The available on-site cyclotron at INMAS provided the requisite PET radionuclide: 18F for the indigenous synthesis of a variety of 18F-based PET-based radiopharmaceuticals (RPs). The PET scan then was obtained on the system following the administration of 18F-labeled RPs such as 18F-fluorodeoxyglucose ([18F]-FDG), 18F-misonidazole, 18F-dihydroxyphenylalanine (DOPA), [18F]-choline for application in oncological and neurological research. The various murine models studied were of BALB/c mice, Sprague–Dawley rats, and tumor-grafted nude mice. Results: In oncological application, the micro PET-CT images of [18F]-FDG and [18F]-choline in murine models mimicked the in vivo pharmacodynamics of these RPs in clinics and these RPs accurately pinpoint the grafted malignant lesions while 18F-fluoromisonidazole scans could further delineate hypoxia region in murine onco models. In neurological studies also, the micro PET-CT scan of 6-fluoro-(18F)-L-3,4-dihydroxyphenylalanine was able to precisely map DOPA receptors in murine brain. Conclusion: We at INMAS have utilized the potential of the small animal system for its advantages of simultaneous molecular and anatomical imaging in vivo. The prospective application of this noninvasive imaging system in neuroscience imaging is enormous owing to the possibilities of longitudinal imaging protocols for improved scientific information.
| PP 23:111346|| |
Pelvic imaging in 68Ga prostate-specific membrane antigen positron emission tomography-computed tomography scan
M. Sowmiya, R. Yurekha, E. R. Radhakrishnan, I. V. Upadhya, F. R. Kingsley, Jephy Joseph, Raghi Jose, KK Kamaleshwaran, Ajit Shinto
Department of Nuclear Medicine and PET CT, Kovai Medical Centre and Hospital, Coimbatore, Tamil Nadu, India
Aim: To delineate the pelvic lesions by pelvic imaging after immediate administration of radiopharmaceutical. Introduction: The pelvic lesions are generally masked because of the radioactive urine in the positron emission tomography (PET) imaging. In this study, the utility of immediate imaging of pelvic region will be evaluated. Materials and Equipment Required: PET scanner, Lasix, Ga68 prostate-specific membrane antigen (PSMA). Methods: The patient will be administrated with Ga68 PSMA radiopharmaceutical. In some cases, immediate pelvic image acquisition will be performed, soon after the injection in the camera room. Then, the routine protocol is followed after the administration of the lasix. The acquisition protocol will be as follows: Topogram for pelvic region. Computed tomography (CT) without contrast injection of Ga68 PSMA, PET CT pelvic (2 beds, 2.5 min/ bed). Result and Conclusion: As this is a prospective ongoing study, the accumulated results will be presented during the meeting, conclusion drawn thereof.
| PP 24:165055|| |
Therapeutic effects of low-dose fractionated X-irradiation on the amyloidβ-based rat model of Alzheimer's disease
Anna Ara Khan, Rozy Kamal1, Vijayta D. Chadha, D. K. Dhawan2
Centre for Nuclear Medicine, Panjab University, 2Department of Biophysics, Panjab University, Chandigarh, 1Department of Nuclear Medicine, Manipal University, Manipal, Karnataka, India
Rationale: Amyloid-β (Aβ) burden has been closely linked to cognitive decline in Alzheimer's disease (AD) patients. The conventional pharmacologic interventions target symptoms but fall short of addressing underlying contributing factors for AD; thus, this study was designed to investigate the therapeutic role of low dose fractionated X-irradiation in targeting β amyloid deposits in Aβ-based animal model of AD. Methodology: Sprague–Dawley (S.D.) female rats received an intracerebroventricular injection of Aβ peptide (1–42) at stereotaxically defined points. Animals were segregated into four groups: sham-operated, β-amyloid injected (1 μg/μl), β-amyloid injection followed by cranial X-irradiation (10 Gy fractionated dose 2 Gy × 5 days) and only cranial X-irradiated group. Aβ plaques assessment was performed in histological sections. Neurobehavioral studies (Elevated Plus maze, Morris water maze, and Active and Passive Avoidance tests) were undertaken to confirm memory impairment along with biochemical indices involved in the antioxidant defense system. Key Results: Significant decrease in the amyloid deposits was observed in the postirradiated group confirmed by histopathological sections of the cerebral cortex. These results were in concordance with the neurobehavioral tests that showed a significant improvement in Aβ-induced memory impairment in the animals subjected to the fractionated dose. Restoration of activity of enzymes involved in the antioxidant defense system (lipid peroxidation, glutathione [GSH], catalase, superoxide dismutase, and GSH reductase) further supported our results. Research Highlights: This study highlights the unexplored role of radiation in treatment of neurodegenerative diseases as it reduces the amyloid plaque burden suggesting a novel treatment for AD-associated pathologies.
| Radiopharmacy|| |
| PP 25:101452|| |
Development of an in vitro technique for assessing the biological behavior of technetium-99m-ethylene cysteine dimer
Soumen Das, Preethi Nair, Anupam Mathur, R. Vanaja, S. S. Sachdev
Radiopharmaceuticals Program, Board of Radiation and Isotope Technology, Navi Mumbai, Maharashtra, India
Introduction: Kit for the preparation of technetium-99m (99mTc)-ethylene cysteine dimer (ECD kit) is a regular product of Board of Radiation and Isotope Technology which is used for brain perfusion imaging. 99mTc-ECD crosses the blood–brain barrier and undergoes enzymatic hydrolysis only inside the brain cells of primates and gets trapped leading to images providing useful clinical information. Thus, the aim of the present work was to develop an in vitro method that, instead of primate testing, would be able to ascertain the biological efficacy of 99mTc-ECD prepared from the kit before injection in patients. Methods: An in vitro enzymatic reaction method was developed, which involved incubating the 99mTc-ECD complex with pig liver esterase enzyme at 37°C and monitoring their action kinetics using high-pressure liquid chromatography (HPLC). The effect of different concentrations of the enzyme (5–50 mg/mL) with 99mTc-ECD substrate kept for various incubation periods (1–4 h) were studied and characterized. Further, to establish the identity of radioactive peaks observed in HPLC spectrum, ECD ligand hydrolysis with the same enzyme was carried and subsequently labeled with 99mTc. Results: HPLC characterization confirmed mono-ester hydrolysis where an additional peak was observed exactly midway between the peaks of 99mTc-diester, 99mTc-diacid, and 99mTc-EC. The simultaneous diester hydrolysis kinetics was poor as increased concentrations of enzyme incubated even for 1 day could not produce 99mTc-diacid product in appreciable yield. However, both the ester groups of ECD ligand got hydrolyzed rapidly on incubation with the enzyme as the crude ECD hydrolyzed product on 99mTc labeling matched with 99mTc-diacid complex. Conclusion: A new in vitro enzymatic method has been developed which can now be used as a means of quality control testing of the ECD kit before using the labeled product in patients.
| PP 26:191544|| |
Process for making sterile evacuated clear colorless glass vials: Used in radiopharmaceuticals production
Arpit Mitra1, Sangita Lad2, Savita Kulkarni2, M. G. R. Rajan3, Sharmila Banerjee1,2
1BRIT, 2Radiation Medicine Centre, BARC, 3Department of Atomic Energy, RRF, Mumbai, Maharashtra, India
Rationale: Producing sterile, pyrogen-free, evacuated colorless glass vials plays critical role in the production of generator-based radiopharmaceuticals (RPs) and dispensing positron emission tomography (PET) RPs in closed lead shielded automated dispenser. In this study, we have developed a process for making sterile, pyrogen-free ready to use USP type-I glass vials without any gamma ray (γ), electron beam (EB), or ethylene oxide (EO) sterilization after evacuation in lyophilizer. Methodology: USP type-I glass vials washed, rinsed (ultrapure water), dried, wrapped (25 μm Al foil) and depyrogenated (250°C 1 h) inside hot air oven. Aseptically, inside clean room (Class 100), bromobutyl rubber closure (γ-irradiated) was placed on vials mouth with depyrogenated forceps. Vials loaded in lyophilizer with shelf and ice condenser temperature preset at −10°C and −55°C, respectively. Pressure was brought down by maintaining vacuum between 0.1 and 0.5 mbar for 45 min, simultaneously the shelf temperature increased to +10°C to extract vapor from vacuum. vial was autosealed under vacuum and aerated using sterile PTFE filter. Vacuumed vials crimped and tested for vacuum integrity by glow discharge method. In accordance with USP/IP, 10% of batch size was tested for sterility, apyrogenecity (gel-clot), and acidity/alkalinity (bromothymol-blue titration). Key Results: All 18,000 evacuated vials produced by in-house developed method comply sterility and pH, while endotoxin limit is <0.06 EU/ml without any γ, EB, or EO treatment. Produced vials had internal vacuum <0.5 mbar with 1% rejections. Research Highlights: We could successfully use these in-housed produced sterile, pyrogen-free, evacuated clear colorless glass vials for automated dispensing and elution of radiopharmaceuticals at our facility.
| PP 27:141442|| |
Insight into small animal imaging in nuclear medicine
Ambika Parmar Jaswal, Anil K. Mishra, Puja P. Hazari
Division of Cyclotron and Radiopharmaceutical Sciences, Institute of Nuclear Medicine and Allied Sciences, Delhi, India
Rationale: From the past 100 years, small animal studies have been an essential element in biomedical research but have been limited to in vitro studies of cellular processes and ex vivo tissue examination from suitable animal models of disease. The need to understand the active biological processes in live small animals has encouraged the development of nuclear imaging modalities with high resolution for preclinical applications. These modalities facilitated the quantitative and radiological evaluation of various preclinical models. Materials and Methods: The intended significance of this study is to highlight the practical use of in-house Trifoil FLEX Triumph Micro-positron emission tomography (PET)/ single photon emission computed tomography (SPECT)/computed tomography (CT), a triple modality system. Co-registered images are acquired without removing the animal from imaging system thereby preserving co-registration. In-house modality use is extensively implemented in radiopharmaceutical screening, assessing pharmacokinetics, biodistributions, and evaluating drug effects to markedly reduce the costs and time required for the new drug development. The small imaging experiments carried out includes both static and dynamic PET/SPECT studies. The various imaging studies such as brain, bone, lung, tumor, and infection were carried out in-house. Various models employed in studies include tumor models, lung hypoxia models, arthritic bone models, and infection models. Results: High-resolution reconstructed, processed, and CT coregistered images were generated. Time-activity curves and standard uptake values too were obtained. Quantitative analysis of the images was performed using AMIRA4.1.1 software. Conclusion: Micro-PET/SPECT/CT system provides a new insight into small animal imaging in nuclear medicine. Above all the system facilitates minimal use of small animal in research.
| PP 28:103543|| |
Synthesis of L-[methyl-11C]methionine
Sachin Sony, Puja Panwar Hazari, Nitin Kumar, Kuldeep K. Panchal, Swatantra, Ram Gopal Meena, Anil Kumar Mishra
Division of Cyclotron and Radiopharmaceutical Sciences, Institute of Nuclear Medicine and Allied Sciences, Delhi, India
Introduction: The majority of positron emission tomography (PET) studies are oncological and use 2-[18F]fluoro-2-deoxy-D-glucose (FDG), but the uptake of this radiotracer is not specific to malignant tissue and indeed uptake may depend on factors other than glycolysis alone. Moreover, high FDG accumulation has been observed recently not only in viable cancer cells but also in inflammatory cells and granulation tissue. Because of this lack of specificity of FDG, other metabolic tracers such as positron emitter-labeled amino acids L-[methyl-11C]methionine are being widely used as indicators of tumor activity. This report describes the synthesis of L-[methyl-11C]methionine in pure form using FXC module. The compound was prepared routinely about 300 times with less than 10 failures. The total time for synthesis was approximately 24 min. Methods: We synthesized 11C-methionine via 11C methylation from L-cysteine thiolactone in solution using the “bubbling” method. 11CO2 was produced by 14N(p,α) 11C reaction. Target gases were passed through cryogenic trap, where 11CO2 was deposited at −165°C. Then, 11CO2 was converted to methane (H2/Ni, 400°C) and 11C-methyliodide was synthesized by passing the 11C-CH4 over iodine in a triplicate loop at an elevated temperature (720°C) and trapping on a Porapak column (dry method). Thermally desorbed 11CH3I was bubbled into the reactor with L-homocysteine thiolactone (2 mg) in a 300 μL solution of 2:1:1 (v/v) 1 M NaOH, ethanol and water at ambient temperature (85°C, 5 min). The product was then purified by semi-preparative high-pressure liquid chromatography (C18 column, 0.05 M NaH2 PO4+ 2% EtOH as mobile phase) with a total wet-synthesis time of 20 min. The final product was formulated with phosphate buffer, passed through a 0.22 μm filter, and dispensed in automatic module DDS-Vials. Result: The synthesis was finished in approximately 25 min and produced 85 mCi with approximately 20% radiochemical yield. Radiochemical purity and radionuclide purity were >98% and >99%, respectively. Conclusion: The final product was free from main radionuclide and chemical impurities. The proposed 11C-methionine synthesis is a reliable tool for routine manufacturing in clinical applications and animal studies.
| PP 29:205158|| |
Rapid physicochemical and biological quality control tests for technetium-99m radiopharmaceuticals: Adapting at nuclear pharmacy
Sangita Lad1, Arpit Mitra2, H. H. Shimpi1, Sharmila Banerjee1,2, Savita Kulkarni1
1Radition Medicine Centre, BARC, 2Medical Cyclotron Facility, BRIT, Mumbai, Maharashtra, India
Rationale: Technetium-99m radiopharmaceuticals (99mTc-RPs) intended for human administration and quality control (QC) tests become important to ensure the safety of these formulations in nuclear pharmacies before patient injections. In this study, we have developed single strip miniaturized chromatography procedures for determining radiochemical purity (RCP) and rapid gel-clot bacterial endotoxin (GC-BE) assay to quantify endotoxin limit (EL) for wide range of 99mTc-RPs. Methodology: 99mTc-RPs (99mTc-MIBI, 99mTc-HYNIC-TOC, 99mTc-EC, etc.,) were labeled as per the standard procedures. Single strip miniaturized ascending chromatography was performed using either TLC-SG (1 cm × 7 cm) or Whatman-3 (0.7 cm × 8 cm) in different solvent system. RCP was evaluated using radio-chromatogram scanner. GC-BE assay was performed for 99mTc-RPs at 5 λ concentration with CaCl2(60 mM). Key Results: For all the studied 99mTc-RPs, various radiochemical impurities (free 99mTcO4−, 99m TcO2, and 99mTc-polar moiety) were well separated along with desired 99mTc-RPs in single strip miniaturized chromatogram on scanning (distinguishable Rf). Modified GC-BE for 99mTc-RPs exhibit solid coagulin gel in positive control while no gel formation in negative control tubes on incubation at 37°C for 25 min. Both of these QC tests could be completed before patient injections within 25 min. Consistent RCP and GC-BE results (RCP: >90% and EL: <25 EU/ml) were obtained for each of the studied 99mTc-RPs (n = 11). Research Highlights: Our results indicate the feasibility of adapting this rapid and cost-effective QC tests (RCP and GC-BE) for all these 99mTc-RPs in nuclear pharmacy or hospital radiopharmacy center before patient injections. With these formulations, if desired QC parameters are not obtained, the 99mTc-RPs cannot be clinically utilized.
| PP 30:162500|| |
Performance evaluation of an indigenous kit for technetium-99m-macroaggregated albumin for lung perfusion imaging
Archana S. Ghodke, Uma Sheri Kumar, R. Krishnamohan, Seema, Neelam Singh Pilkhwal, R. Vanaja, S. S. Sachdev, A. C. Dey
Radiopharmaceutical Programme, Board of Radiation and Isotope Technology, Navi Mumbai, Maharashtra, India
Objective: Kit for the preparation of technetium-99m-macroaggregated albumin (99mTc-MAA) for lung perfusion imaging was being imported and used in India. The need to have an indigenous kit for lung imaging was expressed by physicians, and Board of Radiation and Isotope Technology has developed an indigenous kit for 99mTc-MAA. Six trial batches of the kit were prepared and the kit preparation, formulation, and quality control manual were prepared and submitted to Radiopharmaceutical Committee (RPC) seeking permission for regular production and supply. Following the permission granted by the RPC, regular production and supply of kit for 99mTc-MAA were started from January 2017. More than 450 kit vials have been supplied so far enabling ~1500 investigations with satisfactory reports from the user institutions. The kit was also exported to the USA. Methods: A kit formulation was optimized by dissolving 20% human serum albumin (has) solution, sodium acetate and sodium chloride in water for injection. pH was adjusted to 6.5 and stannous chloride dihydrate was added. Final pH was adjusted to 5.6, and tween 80 was added and stirred well at 90°C for 10 min. After cooling, 1 ml aliquot was dispensed in vials and lyophilized so that each vial contained 2.5 mg of HSA, 10 mg of sodium acetate, 10.8 mg sodium chloride, 0.1 mg stannous chloride dihydrate and tween 80. The kits were evaluated for particle size, radiochemical purity, biological efficacy, sterility, and apyrogenicity. Radiolabeling was done by the addition of Na 99mTcO4 solution to the lyophilized kit vial. Radiochemical purity was assessed by paper chromatography using 85% methanol. Biodistribution was done in Swiss mice at 10 min postinjection. Result: The radiochemical purity of 99mTc-MAA prepared was found to be >95% and the percentage of free pertechnetate impurity was <10%. The size of the particles was within the range of 10–100 μ and number of particles were approximately 450,000 per kit vial. The biological evaluation showed >80% uptake in lungs, <5% in liver, and <5% in spleen. Excellent images of the lungs were reported in humans by the institutions using this product. Conclusion: Regular production and supply of kit for 99mTc-MAA have started from January 2017. Satisfactory reports were obtained from quality control program for all the batches prepared. Satisfactory reports have been received from user institutions when used on humans.
| PP 31:115014|| |
Synthesis of O-(2-[18F] fluoroethyl)-L-tyrosine based on a cartridge purification method: A simple, fast, and high-yielding automated synthesis
Nitin Kumar, Puja Panwar Hazari, Sachin Sony, Swatantra, Kuldeep Kumar Panchal, Ramgopal, Anil Kumar Mishra
Division of Cyclotron and Radiopharmaceutical Sciences, MIRC, Institute of Nuclear Medicine and Allied Sciences (INMAS), Delhi, 110054, India
Introduction: O-(2-[(18)F]fluoroethyl)-L-tyrosine (FET) is widely used as a positron emission tomography tracer for brain tumors. A fluorine-18-labeled analog of tyrosine was synthesized using O-(2′-tosyloxyethyl)-N-trityl-l-tyrosine-tert-butyl ester precursor. In this work, we report an automatic radiosynthesis of FET with a purification procedure based on standard cartridges. Methods: We synthesized [(18)F]fluoroethyltosylate starting from [(18)F]fluoride. After a purification step, L-tyrosine was [(18)F]fluoroethylated with [(18)F]fluoroethyltosylate. The final reaction mixture was purified by means of solid phase extraction. The FET was trapped on an SCX cartridge, eluted with saline solution, and trapped again on an HRX cartridge. For a second purification step, the FET was eluted from the HRX cartridge with ammonium acetate buffer and collected on two SCX cartridges followed by a washing step with water. The final product was eluted with saline solution and neutralized with NaHCO(3) solution (8.4%). Result: The synthesis was finished after 50 min and delivered the FET in a range of 3–16 GBq. The synthesis typically yielded 41% of FET without high-pressure liquid chromatography (HPLC) purification step. The radiochemical purity ranged between 97% and 100%. Conclusion: We present a radiosynthesis of FET where the usually used HPLC purification procedure has been substituted by a purification step based on standard cartridges. This method is useful for automatic modules without an expensive HPLC purification unit and for the routine production of FET.
| PP 32:104258|| |
Development, efficacy, and gamma scintigraphy evaluation of ameliorative curcumin oral formulation for the treatment of ulcerative colitis
Vipin Kumar, Braj Gaurav Sharma, Kushagra Khanna, Harish Rawat, Roop K. Khar, Aseem Bhatnagar
Institute of Nuclear Medicine and Allied Sciences (INMAS), Delhi, 110054, India
Curcumin is the yellow pigment associated with plant turmeric. It is a small molecule that is the prototypical “curcuminoid” and has effects similar to other polyphenols but unique in a way as it is a different class of polyphenol (relative to the other classes of “flavonoid,” “stilbene,” etc.). It exerts potent anti-inflammatory effects, and these anti-inflammatory effects seem to be quite protective against some form of cancer progression and diseases such as Crohn's disease and ulcerative colitis. The aim of the present study was to develop and evaluate a guar gum based novel target release curcumin matrix tablet and its efficacy in animal models against ulcerative colitis, pharmacoscintigraphy study in healthy human volunteers to prove its release in the colon/lower part of gastrointestinal tract (GIT). Formulation was successfully developed and passed through several in-vitro examinations, i.e., in-vitro dissolution, disintegration, hardness, friability, release in presence of rat fecal content, and stability studies. Optimized formulation was radiolabeled with technetium-99m pertechnetate using stannous chloride as a reducing agent and was found stable up to 24 h in normal saline and serum. The radiolabeled formulation was evaluated in six New Zealand white rabbits by gamma scintigraphy in a static manner for the duration of 24 h to observe its retention in the GIT). A similar set of the study was conducted in 12 healthy human volunteers with a similar objective. Scintigraphy images of healthy human volunteer showed retention of optimized formulations in stomach up to 60 min, from where it moved to duodenum further and reached ileum in around 5 h. However, initiation of drug release was observed from intestine at 7 h. Complete dissociation and release of the drug were observed in the colon by the action of colonic bacteria on guar gum.
| PP 33:142800|| |
Development and gamma scintigraphy evaluation of di-sodium alpha ketoglutarate ocular gel for neutralizing the toxic effects of ammonia exposure
Pankaj Sharma, Vipin Kumar1, Braj Gaurav Sharma1, Dhruv Kumar Nishad, Minakshee Chauhan2, Gaurav Mittal, Aseem Bhatnagar
Department of Nuclear Medicine, Institute of Nuclear Medicine and Allied Sciences, Defence R and D Organization, 2NDDS, Delhi Institute of Pharmaceutical Science and Research, Delhi, 1Research and Development Wing, Hetero Healthcare, Hyderabad, Telangana, India
Ammonia and ammonium hydroxide rapidly penetrate into the eye and may cause serious corrosive injury, including, permanent eye damage, or blindness. Alpha keto-glutarate (AKG), an important derivative of glutamine, is considered as a key molecule in trans-membrane amino acid transport, protein metabolism, and both gene and cellular redox regulation. The aim of present study was to develop and optimize ocular gel formulations of di-sodium AKG (D-AKG) to neutralize the toxic effects of ammonia exposure. Different AKG ocular formulations; using carbopol and carmellose sodium (polymer) along with 0.1% benzalkonium chloride (preservative) were prepared. Developed ocular gels were assessed for its clarity, pH, physical appearance, physical stability, viscosity, etc. The selected formulations were subjected for rheological studies, sterility, and in vitro diffusion studies. AKG was radiolabeled with technetium-99m (99mTc)-pertechnatate by adding the optimized reducing agent, i.e., SnCl2. Radiolabeling efficiency of the radio complex was ascertained by the in-vitro and in-vivo examinations up to 24 h. The radiolabeling efficiency was found >95% and proceeded for the scintigraphy evaluation in animal models (New Zealand white rabbit). 99mTc-AKG-based carbopol ocular gel was apply on the eye of rabbit. The percentage of drug retention on rabbit eye at 15, 30, 60, 120, 180, and 240 min was monitored using gamma camera (Symbia-T2, Siemens). The same animal model was also used to evaluate its efficacy against ammonia exposure. It was evident that the optimized AKG-based ocular gels were found transparent and clear in nature. In-vitro drug release data of disodium-AKG-based carbopol 934 gel showed cumulative percentage drug release of 38% at 4 h. Flux and permeability coefficient for same was found to be 13.8 and 0.034, respectively. A parallel study using disodium-AKG-based carboxymethylcellulose showed cumulative percentage drug release of 41% at 4 h. Flux and permeable coefficient for this formulation was found to be12.6 and 0.031, respectively. The in-vivo safety and efficacy evaluation have reflected no significant toxic effects of ocular gel. Ocular irritation test performed on male rabbits showed no redness, inflammation, and tear secretion. Experimental data including scintigraphy data showed that developed gel was found stable, nonirritant, and therapeutically effective against ammonia exposure.
| PP 34:103042|| |
Gamma scintigraphy evaluation of high-density nifedipine oral formulation in gastroparesis subjects
Harish Rawat, Vipin Kumar1, Braj Gaurav Sharma1, Aseem Bhatnagar
Institute of Nuclear Medicine and Allied Science, DRDO, Delhi, 1Research and Development Wing, Hetero Healthcare Pvt. Ltd, Hyderabad, Telangana, India
The delayed gastric emptying is known as the gastroparesis, in which peristaltic movement of the stomach gets slowdown resulting several gastrointestinal disorders. Diabetes mellitus patients, aged population are the largest group of patients having such kind of the disorders. The present work deals with various attempts to prepare an effective locally active formulation of nifedipine for the treatment of gastroparesis. The aim of the present study was to develop a high-density formulation of nifedipine and its pharmacoscintigraphy evaluation in gastroparesis positive patients to examine the therapeutic efficacy. The formulation was developed using 0.5 mg of nifedipine with the combination of barium sulfate to increase the density of formulation. The formulation was subjected to characterize in-vitro for its preformulation and formulation characterization, i.e., density property in gastric simulated media and stability of the formulation. The 12 subjects were recruited on the basis of their previous history related to the poor rate of gastric emptying. Gastric emptying of the subjects was measured by the radiolabeled raw egg methodology a newer approach (Published in previous IJNM issue). The raw egg was radiolabeled by injecting technetium-99m-pertechnetate and optimized concentration of reducing agent, i.e., SnCl2 and then boiled at 100°C for 15 min. Boiled-radiolabeled egg served as a radioactive meal for the determination of gastric emptying begin time, emptying percentage, and T½ value. On the day 1, patients were allowed to eat radiolabeled meal, i.e., egg along with 100 ml of fruit juice. Then, dynamic images (1 s/frame) were acquired for starting 30 min to check the gastric emptying percentage followed by static images 2 min/frame till T½ value reached. On the day 2, same gastric emptying detection protocol was followed. Patients were taken 0.5 mg nifedipine capsule by oral route just after radioactive meal intake. The significant difference with respect to T½ was measured and compared with control values. Results concluded that 42% ± 3.5% fast gastric emptying were monitored in the treatment group. Gamma scintigraphy results indicate the usefulness of the developed formulation in the gastroparesis patients.
| PP 35:184045|| |
Development and characterization of 99mTc/68Ga-labeled ranatensin peptide analogs for targeting bombesin receptors in prostatic cancer
Ajay Kumar, Raunak Varshney1, Anil K. Mishra1, Baljinder Singh
Postgraduate Institute of Medical Education and Research, Chandigarh, 1Institute of Nuclear Medicine and Allied Sciences, DRDO, Delhi, India
Rationale: Bombesin receptors targeting are an extremely promising approach both for diagnosis and treatment of prostate cancers expressing these receptors in the field of molecular imaging and radionuclide therapy. The existing molecular (single photon emission computed tomography [SPECT] or positron emission tomography [PET]) probes either target gastrin-releasing peptide (GRP) or neuromedin B (NMB) subtypes of bombesin receptors. However, it is known that a significant proportion of the prostate cancer patients both GRP and NMB receptors are known to coexist. The rationale is to develop ranatensin peptide-based SPECT/PET agents for targeting both (GRP receptor [GRPR]/NMB receptor [NMBR] in prostate cancer to increase the diagnostic utility over the existing radiotracers). Methodology: The aim was to synthesize DOTA-6-aminohexanoic acid (6AHX)-Aib-Gln-Trp-Ala-Val-Gly-His-Phe-Met-NH2 ranatensin analog with 6AHX as a linker. In this process, analog DOTA-Aib-Gln-Trp-Ala-Val-Gly-His-Phe-Met-NH2 was synthesized by solid phase peptide synthesis using Rink-Amide Am resin using (200–400 mesh), applying the standard 9-fluorenylmethyloxycabonyl (Fmoc) strategy. The product was analyzed by MALDI-TOF-mass spectroscopy (MS). The synthesized peptide (200 μg) was radiolabeled using freshly eluted 99mTc, stannous chloride 5 μg (1 mg/ml of 10% acetic acid), buffer 0.5 M NaHCO3 solution, ascorbic acid 0.2 mg/ml. The complex was incubated for 30 min at room temperature for optimum labeling yield. The labeling efficiency was estimated chromatographically using ITLC-SG strips as stationary phase and 100% acetone (PAW) (3:5:1.5) as mobile phase. Key Results: The ranatensin analog was synthesized and conjugated to bifunctional chelator DOTA with good yield. MS: m/z [m + H +] found 1445.6; calculated 1445.7. Radiochemical purity of the 99mTc-ranatensin analog was always > 90%. Research Highlights: The developed 99mTc/68Ga-labeled ranatensin peptides will increase the sensitivity of the SPECT/PET technique for the detection of prostate tumors which co-express GRPR and NMBR.
| PP 36:153823|| |
Lu177antibody labeling: Our initial experience
Raghi P. Jose, S. Nivetha, Mythili Kameswaran1, Usha Pandey1, A. Dash1, E. R. Radhakrishnan, Indhira Upadhya, Ajit Shinto, Kamaleshwaran K. Karuppuswamy
Department of Nuclear Medicine and PET CT, KMCH, Coimbatore, Tamil Nadu, 1Division of Radiopharmaceuticals, Division of Radiation Biology and Health Sciences, Bhabha Atomic Research Centre, Mumbai, Maharashtra, India
Aim: To demonstrate the preparation of Lu 177rituximab and nimotuzumab using ready-to-use lyophilized kits toward facile preparation at the Hospital Radiopharmacy. Introduction: Radioimmunotherapy is a combination of radiation therapy and immunotherapy used to treat non-Hodgkin's B-cell lymphoma (NHL) and other type of cancers, which uses monoclonal antibodies (Mabs) produced by hybridoma technique. Rituximab is used to treat NHL and nimotuzumab is a humanized Mab against epidermal growth factor, which has also been used for the treatment of lung cancer and glioma. These two antibodies have been labeled with Lu 177and can be used for RIS and RIT. Materials: Lu-177 from BARC, freeze-dried CHX-A”-DTPA-Rituximab, Bn-DOTA-(h-R3)/nimotuzumab] (BRIT cold kit), PD-10 column, water bath, 0.1 M Na acetate, 0.05 M PO4 buffer, 10 mM Na citrate solution for QC, ITLC-SG paper were the materials used. Methods: Labeling of rituximab was at room temperature, while nimotuzumab needed 37°C incubation for 1 h, pure fraction was separated using PD -10 column and the % radiochemical purity (RCP) was checked using 10 mM Na citrate and ITLC-SG paper. Result and Conclusion: %RCP was >90% for both the labeled products, and initial human studies indicate that Lu 177-labeled rituximab and nimotuzumab are simple in-house preparations to obtain potentially suitable radiopharmaceuticals for radioimmunoscintigraphy and therapy.
| PP 37:115437|| |
Continuous quality control of the ITG 68Ge/68Ga generator and production of 68Ga-DOTATATE and 68Ga-PSMA-HBED-CC for clinical studies
Ashok R. Chandak, Hemant H. Shimpi1, Shrinibas Nayak1, Geeta Sonawane1, Swapna Nabar1, Somnath Kar1, Sangeeta Lad1, Sudeep Sahoo1, Sharmila Banerjee1
BRIT, Navi Mumbai, 1RMC, BARC, TMH Annex, TMC, Mumbai, Maharashtra, India
Objective: Performance of ITG 68Ge/68Ga generator system in Eckert Ziegler module system and production of 68Ga-DOTATATE and68Ga-PSMA-HBED-CC were tested over 6 months using strong cation exchange (SCX) cartridge and 1 M sodium acetate buffer (acidic 5 M NaCl as eluent) method. Materials and Methods: Performance of 68Ge/68Ga generator 50 mCi (1850 MBq) was characterized and it was eluted with 0.05 (N) HCl (4–8 mL) for the preparation of 68Ga-DOTATATE and 68Ga-PSMA-HBED-CC. Weekly elution profiles of 68Ga elution yield and 68Ge breakthrough were determined. The strata XC is replaced with strata SCX cation exchanger and acidified acetone (0.8 ml) is replaced with acidic 5 M NaCl (0.5 ml) as eluent. Results: 68Ga elution yields averaged 92% (84.8%–98.4%) and 68Ge breakthrough averaged 0.002% (0.009%–0.004%). The radiochemical purities of 68Ga-DOTATATE and 68Ga-PSMA-HBED-CC were determined by ITLC (SG) analysis to be >98% and >96%, respectively. First-day 68Ga activity eluted was reached to 27 mCi (990 MBq) at the time of this work. 68Ga contamination in the product was under the detection limit (0.0001%). Final sterile, pyrogen-free formulation of 68Ga-DOTATATE and 68Ga-PSMA-HBED-CC in physiologic saline with 3%–5% (V/V) ethanol (50% V/V) and labeling yield was found 62% (55%–68%) was achieved. Conclusion: Performance of ITG 68Ge/68Ga generator in Eckert and Ziegler modular system was studied over 6 months with satisfactory results. The loss of free 68Ga was >15% at the time of purification with strata XC using acetone method which is reduced to less than 1% using strata SCX with sodium chloride method. The generator eluate was used to synthesize 68Ga-DOTATATE and 68Ga-PSMA-HBED-CC on a routine basis with high yield and high purity.
| PP 38:152502|| |
Automated synthesis of clinical grade [68Ga]-prostate-specific membrane antigen-11 for use in prostate cancer patients in a radiation medicine center
Shrinibas Nayak, Amit Kumar, Sharmila Banerjee
Medical Cyclotron Facility, Radiation Medicine Centre, BARC, Mumbai, Maharashtra, India
Rationale: [68Ga]-prostate specific membrane antigen (PSMA)-11 is a positron emission tomography tracer for targeting PSMA and can be used for staging prostate cancer. This tracer can be used for planning individualized endoradiotherapy when used in combination with its theranostic pair [177Lu]PSMA-617. A number of methods for 68Ga-labeling have been developed. Production for the clinical use can be divided into three groups, viz., manual, automated, and kit type GMP preparation. The use of automated module has multiple advantages. One of which is 68Ga purification and its preconcentration before radiolabeling. Inclusion of this step not only removes metallic impurities from generator eluate but also allows use of the entire 68Ga elution volume. This enables maximum utilization of the 68Ga activity per elution for radiolabeling. Preconcentration helps in the production of high specific activity of labeled peptides. The second advantage is SPE-based product purification which ensures radiochemical purity of [68Ga]PSMA-11, irrespective of radiolabeling yield. Methodology: [68Ga]PSMA-11 was synthesized after purification and preconcentration of 68Ga eluate and the product was purified using C18 reverse-phase cartridge in automated synthesis module from Eckert and Ziegler. Key Results: Radiolabeling yields obtained were consistently >90% and radiochemical purity of product was more than 99%. Research Highlights: We have optimized the automated synthesis procedure for [68Ga]PSMA-11 using ready-to-use formulation and applied successfully for routine production of over 40 batches using 68Ga activity in the range 5–35 mCi in a hospital-based radiopharmacy setting in a radiation medicine center for using in prostate cancer patients.
| PP 39:120018|| |
Evaluation of biodistribution of fractionated MIBI kit (TCK 50)
Sutapa Rakshit, Ashok R. Chandak, H. H. Shimpi, Yogita Pawar, Nawab Sigh Baghel, Sharmila Banerjee
Radiation Medicine Centre, Mumbai, Maharashtra, India
Objectives: The aim of this study was to compare the biodistribution of fractionated technetium-99m sestamibi (99mTc-MIBI) at different time points and compare with routine 99mTc MIBI kit of Board of Radiation and Isotope Technology (BRIT). Introduction: A single cold kit vial supplied from BRIT has been used to prepare radiopharmaceuticals for multiple patients' doses which often remain unutilized to the full extent. Fractionation of cold kit will suffice the economically effective use of the product in low volume nuclear medicine department. In the fractionated kit, stannous chloride was added and used nitrogen purged saline to maintain stability in the radiolabeled product. Biodistribution was compared with routine lyophilized MIBI kit. Materials and Methods: 99mTcO 4−, lyophilized MIBI kit and fractionated MIBI vial, Universal pH paper, gamma-TLC miniGITA scanner, chemicals used AR/HPLC grade, NaI (Tl) scintillation counter, isotope dose calibrator were the materials used. The kit was labeled with 99mTcO 4− from column generator and the labeled products were checked for pH, color, and % radiochemical purity (% RCP). Animal biodistribution study was performed in Wistar rats (n = 3/group); about 0.2 ml (~ 100 MBq) 99mTc-MIBI was injected through the tail vein of the rat (5th day and 20th day of fractionated vial). Experimental animals were sacrificed 1 h postinjection and all organs of interest were excised. The obtained biodistribution data was calculated as percent injected dose per gram and per organ. Further scintigraphy myocardial perfusion imaging has been studied in the rabbit under single photon emission computed tomography (SPECT) camera. Results: The kit was found stable for 20 days stored at freezing condition with the addition of 150 μg SnCl2.2H2O, pH 5.5–6.0, RCP > 98%. 3.15% and 4.12% myocardial tissue uptake found in the rat on 5th day and 20th day, respectively. Heart perfusion study (SPECT) on the 20th day of fractionation using rabbit found satisfactory and which is comparable with the unfractionated MIBI kit. Conclusions: The physicochemical parameters of fractionated kit found as per the specification of IP 2014. Animal biodistribution and scintigraphy imaging studies with fractionated kit showed comparable results with the routine product kit. Further, this study confirm that the use of increased quantity of SnCl2.2H2O and nitrogen purged saline helps extend the stability of fractionated kit which is useful for low volume nuclear medicine department to use the product cost-effectively.
| PP 40:105436|| |
Radiochemical purity of manually prepared Ga-68 radiopharmaceuticals
Nicholsen Gershom, Merlin Jolly, E. R. Radhakrishnan, I. V. Upadhya, F. R. Kingsley, Jephy Joseph, Raghi Jose, KK Kamaleswaran, Ajit Shinto
Department of Nuclear Medicine and PET CT, Kovai Medical Centre and Hospital, Coimbatore, Tamil Nadu, India
Aim: To check the quality of manually prepared Ga-68 radiopharmaceuticals (68Ga Dota and 68Ga PSMA) by radiochemcial purity test. Introduction: 68Ga is obtained from 68Ge generator. The radiopharmaceuticals prepared in our department manually are 68Ga PSMA and 68Ga DOTA TATE/NOC/TOC. ITLC-SG chromatography is a very rapid and practically convenient method of purity check. Materials: ITLC-SG chromatography paper, micropipette, acetonitrile, and high-pressure liquid chromatography (HPLC) water. Methods: Quality check of 68Ga radiopharmaceuticals are performed by ITLC SG as a stationary phase and acetonitrile: HPLC water 1:1 as a mobile phase. The QC data from January 2017–August 2017 for 68Ga radiopharmaceuticals will be presented in a graphical format, during the meeting. Results: The average % radiochemical purity for both the 68Ga radiopharmaceuticals was found to be more than 90%. Conclusion: The % radiochemicial purity test performed by ITLC-SG and 50% acetonitrile was found to be a good-quality indicator for manually prepared 68Ga radiopharmaceuticals.
| PP 41:214123|| |
Radiolabeling, stability, and in-vitro evaluation of 99mTc-HYNIC-AE105 for tumor imaging
V. V. Murhekar, Shalaka Paradkar, Anupam Mathur, B. L. Malpani, D. Padmanabhan, A. G. Korde
Radiopharmaceutical Program, Board of Radiation and Isotope Technology, Navi Mumbai, Maharashtra, India
Rational: Peptide receptor radionuclide imaging and therapy is considered as the landmark in the diagnosis and treatment of tumors. Urokinase plasminogen activator receptor (UPAR) is overexpressed in cancers with high metastatic potential. Studies with UPAR-binding peptides radiolabeled with positron emission tomography isotopes are reported to be promising for tumor imaging and therapy. Availability of technetium-99m (99mTc0 UPAR binding ligand will find wider applicability for detecting tumors with high metastatic potential. A 9 mer peptide D-Cha-F-s-r-Y-L-W-S (AE105) exhibits high affinity toward UPAR; hence, we report here radiolabeling and in-vitro evaluation of AE 105 labeled with 99mTc. Methodology: HYNIC derivative of AE105 was labeled with 99mTc using co-ligand tricine; reagent concentration and reaction parameters were optimized. Purification of 99mTc-HYNIC-AE105 was carried out using radio-high pressure liquid chromatography over C-18 reverse phase column using water:acetonitrile gradient. Stability of the tracer was studied both in saline as well as in human serum at 37°C. Binding of the tracer to UPAR was carried out with recombinant UPAR in soluble form and using U87MG glioblastoma cells expressing UPAR, and 100-fold excess ligand was used to study specificity of uptake. Key Results: Maximum labeling yield (~80%) was obtained using 30 μg HYNIC-AE105 peptide, 40 μg tricine, and 100 μg of SnCl2. Labeled peptide has a retention time of about 19 min at standardized chromatographic conditions. The radiochemical purity was >95% and purified 99mTc-HYNIC-AE105 showed 8.5% specific binding to soluble UPAR. Cell kinetic studies showed decrease in binding with time; however, specificity of binding was observed in studies carried out up to 120 min of incubation. Conclusion: 99mTc-HYNIC-AE105 could be prepared in high yield and >90% purity. The specificity of tracer for UPAR was evident from in-vitro studies. Further work is warranted to evaluate kinetics and in-vivo specificity.
| PP 42:200821|| |
Design, synthesis, and development of 44Sc-(1, 4, 7, 10 tetrazacyclodecane-1yl)1, 4, 7 triacetic acid -lipid conjugate: Theoretical insight and preclinical evaluation for positron emission tomography and single photon emission computed tomography imaging
Anju Wadhwa, Shubhra Chaturvedi, Deepa Bhadouria, Preeti Jha, Sunil Pal, Firasat Hussain1, A. K. Mishra
Division of Cyclotron and Radiopharmaceutical Sciences, INMAS, DRDO, 1Department of Chemistry, University of Delhi, North Campus, University Enclave, Delhi, India
Objective: Imaging brain requires radiopharmaceuticals which not only confer properties of ideal radiopharmaceutical but also are capable of crossing the blood–brain barrier. Derivatives of cyclen, 1, 4, 7, 10 tetrazacyclodecane-1yl)1, 4, 7 triacetic acid (DO3A), or dithylenetriaminepentaacetic acid (DTPA) impart hydrophilic character to the overall complex. Lipidization of DO3A offers solution to increase lipophilicity of the ligand without perturbation in the binding affinity of the targeting moiety. Herein, we report the synthesis, physical properties, and evaluation of C-18-lipidized DO3Aas a novel positron emission tomography/single photon emission computed tomography imaging agent. Materials and Methods: After the tri-protection of cyclen, the resulting DO3A was functionalized as primary amine by conjugation with bromoethyl amine. NHS-activated stearic acid was conjugated to DO3A by amide linkage, resulting in the formation of lipidic-DO3A macrocycle. Characterization was carried using various analytical techniques. Metal complexes stability constant was evaluated using in silico density functional theory (DFT) and potentiometric for PET/SPECT relevant metals - gallium and scandium and other metals. Cold labeling with gallium and scandium was optimized using high pressure liquid chromatography (HPLC). Results and Discussion: The lipid-DO3A macrocycle was obtained in ≈80% yield. The purity of the final compound was further confirmed by high-resolution mass spectrometry (m/z = 642.7) and HPLC. Cold metal labeling has been performed and HPLC profiles have been established using acetonitrile-water as the mobile phase. DFT calculations are underway. Future work will concentrate on toxicity evaluation and hot labeling. Research Highlight: Novel chelating system for brain imaging based on DO3A lipdic conjugate evaluated for metal complexation properties.
| PP 43:200139|| |
Synthesis, in silico studies, and preliminary in vitro/vivo evaluation of nucleoside-capped silver nanoparticle as dual imaging agent for brain imaging
Deepa Bhadouria1,2, Shubhra Chaturvedi1, Sangeeta Lal3, Ankur Kaul1, Anju Wadhwa1, P. Sen3, Aruna Chhikara2, Anil K. Mishra1
1Division of Cyclotron and Radiopharmaceutical Sciences, INMAS, DRDO, 2Dyal Singh College, University of Delhi, 3School of Physical Sciences, Jawaharlal Nehru University, Delhi, India
Objective: Nucleosides, the building block for nucleic acids, have been extensively exploited for imaging. However, with limited intracellular passive diffusion, the tracer's utility is restricted especially for brain imaging. This can be achieved through modified nucleosides, viz., ketalized nucleosides, wherein the hydrophilicity is reduced. Thus, as a proof-of-concept, lipidic nucleosides have been loaded on silver nanoparticles (Ag-NPs) and assessed for brain penetration. Due to the antimicrobial properties of Ag-NPs, the future application of tracer may also extend in therapeutics. Methods: The synthesis involves ketalization at 2',3' of uridine, followed by azidation at 5' position. The 5'-azide was reduced to amine (DAU-amine) which was converted into thiol (-SH) using Traut's reagent followed by in situ conjugation with Ag-NP (≈5nm). The compounds were thoroughly characterized. Physical characterization was carried. The nanoparticles were radiolabeled with 99mTc and evaluated for radiolabeling parameters and biodistribution. Results: Ag-NPs were synthesized by electroexplosion of wire (EEW) technique. The final compound DAU-amine (m/z = 284) was synthesized with 30% yield. Conversion of amine to thiol using Traut's reagent and in situ conjugation of DAU-thiol with Ag-NPs was successful, as confirmed by ultraviolet–visible. The disappearance of the characteristic Ag-NPs peak at ≈400 nm and the appearance at 386 nm confirmed the conjugation. Cytotoxicity studies using HEK cell line do not indicate toxicity. Technetium radiolabeling has been standardized using stannous tartrate with ≥95%. Biodistribution and imaging studies are underway. Research Highlights: Brain imaging agent using Ag-NPs capped with nucleosides of enhanced lipophilicity to serve as dual imaging agent for extended application in therapy of infections.
| PP 44:101003|| |
Studies toward elucidating the potential of 5, 10, 15, 20-tetrakis (p-carboxy-methyleneoxyphenyl) porphyrin as a theranostic vector for applications in positron emission tomography and photodynamic therapy
Mohini Guleria1, Chandan Kumar1, Tapas Das1,2, Jeyachitra Amirdhanayagam1, Rohit Sharma1, Haladhar D. Sarma3, Ashutosh Dash1,2
1Radiopharmaceuticals, Bhabha Atomic Research Centre, 2Homi Bhabha National Institute, 3Division of Radiation Biology and Health Sciences, Bhabha Atomic Research Centre, Mumbai, Maharashtra, India
Rationale: Porphyrins, owing to their inherent tendency to accumulate in tumorous lesions, are considered suitable for developing agents for theranostic applications involving tumor diagnosis and targeted tumor therapy. The aim of the present work is to study the potential of a porphyrin derivative, namely, 5, 10, 15, 20-tetrakis(p-carboxymethyleneoxyphenyl)porphyrin (SPTA) as a theranostic vector for applications in positron emission tomography (PET) and photodynamic therapy (PDT). Methodology: SPTA was synthesized in-house following a three-step reaction process and characterized by spectroscopic techniques, viz., ultraviolet–visible, Fourier-transform infrared, 1H-nuclear magnetic resonance (NMR), 13C-NMR spectroscopy as well as by mass spectrometry. SPTA was labeled with 68Ga, a generator-produced PET radioisotope, and the radiolabeled product was characterized by high pressure liquid chromatography. Diagnostic potential of 68Ga-SPTA was evaluated by cell binding studies in two different tumor cell lines (HT1080 and AT549) as well as by biodistribution studies in Swiss mice-bearing fibrosarcoma tumors. The therapeutic potential of SPTA was evaluated by determining its photocytotoxity employing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium assay in the same tumor cell lines. Key Results: The 68Ga-SPTA complex was prepared with a radiochemical purity >95% under the optimized conditions. In-vitro cell binding studies revealed affinity of 68Ga-SPTA toward the cancer cells while biodistribution studies exhibited accumulation of the radiotracer in tumor. In-vitro photocytotoxicity studies performed in HT1080 and AT549 cell lines indicated significant cytotoxicity of SPTA in presence of light. Research Highlights: The present study indicates the possible potential of SPTA in radionuclidic imaging as well as in PDT, thus confirming the promising theranostic nature of the porphyrin derivative.
| PP 45:000420|| |
Estrogen receptor imaging using 16α-[F-18]-fluoro-17β-estradiol: An institutional experience
Rakhee Vatsa, Jaya Shukla, B. R. Mittal
Department of Nuclear Medicine, Post Graduate Institute of Medical Education and Research, Chandigarh, India
Rationale: Estrogen receptor (ER) plays a key role in development and progression of breast cancer, and ~75% of breast cancer overexpress ER receptors. Evaluation of receptor status is usually done by immunohistochemical which is invasive. In the present study, 16α-[F-18]-fluoro-17β-estradiol (F-18 FES), an ER-specific positron emission tomography (PET) imaging agent, was synthesized using automated module and was evaluated in breast cancer patients. Methodology: F-18 was produced via 16O (p, n) 18F reaction in the medical cyclotron facility of the department. Synthetic analog of estradiol was labeled with F-18 via nucleophilic substitution reaction in fully automatic module. After assembling and fixing the cassette in module, tests were performed to ensure proper connections. All reagents and precursor were placed at their respective positions. Purification of the product was done using cartridge-based solid phase extraction method. Total synthesis time post F-18 delivery was ~50 min. After performing quality control of F-18 FES, 5–7 mCi of was administered intravenously to breast cancer patients (n = 5). Whole-body PET-computed tomography scans were acquired 45–60 min postinjection. Key Results: F-18 FES was produced successfully using cassette-based automatic synthesis module with 25%–30% yield. Quality control parameters indicated suitability of RP for intravenous administration. Radiopharmaceutical was well tolerated by patients. Excretion of product was observed primarily through liver followed by renal clearance. Good radiotracer uptake was noticed in the lesions. Research Highlights: Facile synthesis of F-18 FES can be done using cassette-based automated modules. F-18 FES can be used for noninvasive imaging of ERs which may help in better patient management.
| PP 46:151934|| |
Comparison of in-house prepared tricarbonyls versus kit-based method for labeling tamoxifen
Anupriya, Jaya Shukla, Priya Bhusari, Rakhee Vatsa, Kanchan Palarwal, Yogesh Rathore, B. R. Mittal
Department of Nuclear Medicine and PET Centre, PGIMER, Chandigarh, India
Rationale: Tricarbonyls are small-sized complex having metal in its center. Three molecules of carbon monoxide and water act as ligands. These can be used in the preparation of various diagnostic and therapeutic radiopharmaceuticals. In this study, tamoxifen (tam) was labeled using in-house prepared technetium (Tc-99m) tricarbonyls and kit-based tricarbonyls and results were compared. Methodology: Tc-99m (5–30 mCi) was added to readymade kits. After incubating the reaction vial for 20 min at 80°C, 1 mg tam was added followed by another incubation of 30 min. For in-house preparation, potassium tetraborate, sodium tartrate, sodium boranocarbonate, and sodium carbonate were added and incubated with 5–30 mCi Tc-99m in water bath for 20 min. To rule out the possibility of free Tc-99m, carbonyl solution was incubated with 0.05 M ethylenediaminetetraacetic acid (EDTA) solution. Paper chromatography was done in saline and acetone. Tam was added and incubated at 100°C. Characterization of both products was done using mass spectra. Radiochemical purity was done using saline and methanol:HCl (99:1) as mobile phase. After this, single component method was tried using sodium boranocarbonate. Quantity, incubation timings, and amount of tam were optimized for maximum radiolabeling yields. Key Results: Paper chromatography results were same in all three methods. Tc-99m-carbonyls and Tc-99m-carbonyl-tam showed Rf of 0.9 and 0.2, respectively, with saline and 0.3 and 0.4, respectively, with methanol:HCl. No free Tc-99m was present in the solution after incubation as peak was observed at solvent front in acetone of EDTA-containing solution. Mass spectra showed peak at their respective molecular weights - 234 Da and 568 Da. Research Highlights: Tc-99m carbonyls can be prepared successfully in-house using only single component reducing the cost of synthesis of radiopharmaceuticals as tricarbonyls can be used for production of various radiotracers.
| PP 47:081440|| |
Optimization of in-house synthesis of 68Ga-labeled radiopharmaceutical by implementation of quality assurance procedures
Bhakti Shetye, Priya Monteiro, Mehjabeen Pathan, V. Rangarajan
Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Hospital, Mumbai, Maharashtra, India
Rationale: Labeling efficiency of 68Ga-labeled products can be optimized by implementation of quality assurance procedures as various factors influence on it. We evaluated optimization of labeling efficiency of 68Ga-labeled radiopharmaceuticals following quality assurance steps. Methodology: Using ITG fluidic module, labeling efficiency of 68Ga-DOTANOC (25 μg) and 68Ga-PSMA (5 μg) synthesized manually was evaluated for five nonmetallic column generators. All reagents weighed on calibrated analytical balance and prepared in millipore water to ensure purity of stalk solution. Dispensing was done using calibrated micropipette taking small quantity in plastic lid to minimize contamination of reagents. Fractionated peptides stored in low bind microcentrifuge tube for its full recovery. At 95°C, proper delivery of peptide was ensured by measuring count-rate over reactor, cartridge. RCP (ITLC using 0.1 M sodium citrate) and stability of the product were evaluated. Key Result: Total 618 synthesis (68Ga-DOTANOC =236, 68Ga-PSMA = 382) was performed using five generators. Taking proper precautions and minimizing manual errors, the labeling efficiency improved as 77%–78% (DOTANOC) and 78%–80% (prostate-specific membrane antigen) for remaining generators. Research Highlights: Our data showed improved labeling efficiency and consistent RCP by implementing quality assurance procedures permitting use of generators cost-effectively.
| PP 48|| |
Comparison of 64Cu-labeled diaminedithiol (N2S-benzyl)2-peptide and 1, 4, 7-triazacyclononane,1-glutaric acid-4,7-acetic acid peptides for imaging prostate cancer
Sushil Kumar Tripathi1, Pardeep Kumar1, M. L. Thakur1, 2, 3, 4
Departments of 1Radiology, 2Radiation Oncology and 4Urology, Thomas Jefferson University, 3Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, United States
Introduction: Reproducible radiolabeling yield and in vivo stability of labeled conjugates are the two most important parameters of a successful radiopharmaceutical for imaging. These parameters are primarily governed by the choice of a chelating agent. Our laboratory has developed a 64Cu-diaminedithiol (N2S-benzyl)2-peptide (N2S2) that targets VPAC-1 receptors and successfully images breast, bladder, and prostate cancer (PCa) in humans. Recent literature suggests that 1, 4, 7-triazacyclononane,1-glutaric acid-4,7-acetic acid (NODAGA) could be an another promising chelating agent. The objective was to investigate the radiolabeling efficiency and in vivo stability 64Cu-NODAGA and 64Cu-N2S2-peptide specific for VPAC receptors for detection of prostate cancer (PCa) xenograft grown in athymic nude male mice. Methods: N2S2-peptide and NODAGA-peptides were synthesized and radiolabeling method was developed for each. The positron emission tomography (PET) conjugates were injected i.v. into separate groups of PCa-bearing male mice. Mice were PET imaged 2 h after injection and sacrificed for tissue distribution. Clearances of the two conjugates were monitored through urine collected at different time points, and stability was examined with radio-high pressure liquid chromatography (HPLC) and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE) analysis. Results: For 64Cu-N2S2-peptide and 64Cu-NODAGA-peptide, the chelator: peptide ratio was 1:1. Radiochemical yields for both compounds were comparable (≥95%) and no further purification was required. Tumor uptake with 64Cu-N2S2-peptide was 7% ± 2% ID/g as compared to 2% ± 1% with 64Cu-NODAGA-peptide. With 64Cu-NODAGA-peptide,>70% activity was excreted through urine as compared to only 2% of 64Cu-N2S2-peptide. Radio-HPLC of urine collected from 64Cu-NODAGA-peptideinjected mice showed a retention time 4.3 min as compared to 5.3 min for 64Cu-NODAGA-peptide. 64Cu-N2S2-peptide excreted in urine had the same retention time (5.3 min) as that of 64Cu-N2S2-peptide. The stability of both the complexes was further confirmed with SDS PAGE analysis. 64Cu-N2S2-peptide complex remained stable (100%) even for 2 h postinjection as compared to <20%64Cu-NODAGA at 30 min postinjection. Conclusions: These studies demonstrate that N2S2 is a better chelating for 64Cu than NODAGA. 64Cu-N2S2- peptide is highly stable and has greater PCa uptake than 64Cu-NODAGA-peptide.
Acknowledgement: The research, in part, was supported by NIH/NCI RO1CA157372 (MLT), NIH/NCI 1S10OD012406 (MLT), and NIH/NCI S10RR23709 (MLT).
| PP 49:161131|| |
Peptidic (99mTc-DO3A-IKVAV) brain imaging probe for single photon emission computed tomography imaging: Synthesis and evaluation
Raunak Varshney, Sandhya Rangaswamy, Rashi Mathur, Ankur Kaul, Anil K. Mishra
Division of Cyclotron and Radiopharmaceutical Sciences, Institute of Nuclear Medicine and Allied Sciences, Delhi, India
Rational: Imaging is facilitating to identify neural networks involved in cognitive processes to understand, recognize, and diagnose the disease pathways. The synthesized peptide has high potency for laminins, which are overexpressed in Alzheimer's disease and Down's syndrome, and can be an efficient target of neuroimaging. The rationale of this study was to develop modified DO3A-IKVAV for brain imaging by facile solid phase synthesis. Methodology: The peptide was synthesized on solid phase by Fmoc-chemistry. The N-terminal of isoleucine on resin was alkylated with the help of chloro-acetyl-chloride in N-methyl-2-pyrrolidinone/N, N-diisopropylethylamine and conjugated to DO3A in the presence of K2 CO3. On completion, the peptide conjugate (DO3A-Ile-Lys-Val-Ala-Val) was cleaved from resin using trifluoroacetic acid cocktail. The conjugate was radiolabeled with technetium-99m (99mTc) in aqueous solution at pH 6.5–7.5. Key Results: The synthetic yield of DO3A-IKVAV was 75% yield. The retention time of HPLC purified peptide-conjugate was 11.49 min and molecular mass 914.7[M]+. The conjugate binds with 99mTc with high specific activity and efficiency (98.4%). The stability in serum indicated that 99mTc remained bound to the drug up to 24 h. The in vivo biodistribution and blood kinetics studies exhibited rapid clearance of the radiolabeled complex and excretion through the hepatobilliary and renal route. Research Highlight: The cytotoxicity and hemolytic studies revealed that the peptide conjugate was nontoxic up to 500 μM and maximum percentage of erythrocytes lysis was observed to be 5.63. The pharmacokinetics of 99mTc-DO3A Ile-Lys-Val-Ala-Val shows substantial accumulation in brain 1.52% ± 0.15% ID/g at 10 min. The blood kinetics exhibit a fast wash out. The retention of ligand in brain and good pharmacokinetics suggests efficacy of 99mTc-DO3A-IKVAV as potential single photon emission computed tomography imaging probe.
| PP 50:101228|| |
Evaluation of fate of tryptophan functionalized superpramagnetic iron oxide nanoparticles for tumor targeting using single photon emission computed tomography imaging
Rashi Mathur, Ramprakash Chauhan1, Ankur Kaul, Raunak, Sweta Singh, Anil Kumar Mishra
Division of Cyclotron and Radiopharmaceutical Sciences, Institute of Nuclear Medicine and Allied Sciences, Delhi, 1Department of Chemistry, SVGC Ghumarwin, Bilaspur, Himachal Pradesh, India
Rationale: Amino acids have a dual role in cellular metabolism as they are both the building blocks for protein synthesis and intermediate metabolites which fuel other biosynthetic reactions. Tumors cells also use various amino acids present in our bodies as nutrients for their own growth and proliferation. Hence, we have synthesized superpramagnetic iron oxide nanoparticles (SPIONs) functionalized with tryptophan enhanced targeting of tumors, i.e., ovarian, lung, colorectal, etc., over expressing their transporters. Methodology: Tryptophan is conjugated to the SPION using 3-aminopropyltrimethoxysilane as a linker. The synthesized tryptophan-conjugated magnetic nano-conjugate has been characterized comprehensively for its shape size, charge, magnetism, and conjugation. The in vitro cell studies and phantom magnetic resonance (MR) studies were performed. The pharmacokinetics, biodistribution, and tumor uptake of the nano-conjugate were studied by labeling it with technetium-99m. Key Results: The magnetization studies show magnetic attenuation after conjugation as expected; however, the desired superparamagnetic property is still retained as shown by the signature sigmoidal B-H curve. The nano-conjugate shows minimal cytotoxicity over 24 h as shown by the SRB assay in two cell lines A-549, MCF-7. The MR phantoms showed higher T2 relaxation. The radiolabeled magnetic nanoconjugate showed 97%–98% stability over 24 h. The pharmacokinetics, bio-distribution, and scintigraphy support each other to enable us to infer higher target to nontarget at the tumor site. Research Highlights: This study highlights the suitability of the designed magnetic nanobioconjugate as a potential bimodal diagnostic agent and also shows the ease with which the in vivo dynamic behavior of SPION can be studied.
| Oncology and Metabolic|| |
| PP 51:150718|| |
Synthesis and preliminary evaluation of diethylene-triamine-pentaacetate acid-bis(thymidine) as a single photon emission computed tomography imaging agent for tumor targeting
Shivani Singh1,2, Sweta Singh1, R. K. Sharma1, Ankur Kaul1, Rashi Mathur1, Anil K. Mishra1
1Division of Cyclotron and Radiopharmaceutical Sciences, Institute of Nuclear Medicine and Allied Science, 2Department of Chemistry, University of Delhi, New Delhi, India
Aim: In cancer cells, there is increased DNA synthesis and the role of nucleosides in this process was associated to cell proliferation. 18F-radiolabeled thymidine has emerged as a standard measure for the cell growth as thymidine, among all of the nucleic acid bases, was unique for DNA and it is not incorporated into RNA. Thus, retention of this radiolabeled base demonstrated the extent of DNA synthesis as well as cell replication. To explore a radiolabeled thymidine as an imaging probe involves a broad knowledge of the mechanism of DNA incorporation and knowledge of its wash-out and metabolism. All of the radioactivity existing in a given volume of the element is quantified using positron emission tomography/single photon emission computed tomography (PET/SPECT), regardless of the molecular entity under question because imaging using PET/SPECT cannot discriminate the molecular form of the tracer detected. Thus, one must choose radiolabeled compounds which are trapped by pathways of concern, and thus, the presence of a concentration higher than the background demonstrates specific retention, whereas an untrapped tracer or the metabolites are washing-out from the tissue and might be contributing to a nonspecific background. Thus, in this report, we have synthesized and evaluated a diethylene-triamine-pentaacetate acid-bis(thymidine) (DTPA-bis[Th]) to be consequently labeled with technetium-99m and used as a SPECT imaging agent. Materials and Methods: The synthetic strategy for the synthesis of DTPA-bis(Th) involves the protection of the amine functional group of BEA using boc-anhydride. The -Br group of the boc-BEA was then substituted with thymidine at N-3 position using DMF and K2 CO3. The boc group was removed in acidic medium using trifluoroacetic acid. Then, the amine group of thymidine ethyl amine was conjugated with DTPA bisanhydride using DMF and K2 CO3. Thus we have developed a new SPECT-based imaging agent. All the products are characterized by electrospray ionization-mass spectrometry, 1H-nuclear magnetic resonance (NMR), and 13C-NMR. Results: Radiolabeling was achieved above 97% and radio conjugate is stable for 24 h in human serum and get dissociated less than 0.5%. The biological studies are under progress. The overall synthesis time, from EOB to high-pressure liquid chromatography (HPLC) analysis DTPA-bis(Th) was 40 min and the retention time was found to be 5.2 min radiolabeled analog. Specific activity was 122–174 GBq/mmol. Radiochemical purity determined by analytical radio-HPLC was higher than 98%. Cytotoxicity was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay.
| PP 52:091520|| |
The correlative study of 16α-(18) F-fluoro-17β-estradiol positron emission tomography/computed tomography and 2-deoxy-2-[Fluorine-18] fluoro-D-glucose positron emission tomography/computed tomography in breast cancer patients
Arpana Arbind, Nikhil Seniaray, Harshul Sharma, Abhinav Jaimini, Maria D'Souza, Santosh Pandey, Anupama Datta1, A. K. Mishra1, Rajnish Sharma, Anupam Mondal
Department of PET Imaging, Institute of Nuclear Medicine and Allied Sciences, 1Division of Cyclotron and Radiopharmaceutical Science, Institute of Nuclear Medicine and Allied Sciences, New Delhi, India
Background: Breast cancer treatment is now becoming more personalized and targeted so, for this modern imaging techniques such as 16α-(18) F-fluoro-17β-estradiol positron emission tomography/computed tomography (18 F-FES PET/CT) scan is excellent tool. It is also not possible to know the estrogen receptor (ER) status of all lesions in single setting due to infeasibility in biopsy sampling from all metastatic sites. PET/CT with (18F) FES is unique method to determine the molecular information of functional ER expression non-invasively in whole-body (WB) basis. Materials and Methods: Ten patients of biopsy-proven breast cancer were subjected to both WB (18F) FES and fluorodeoxyglucose (FDG) PET/CT in our Centre. Around 222 MBq of FES and around 370 MBq of FDG were injected intravenously on different days, and approximately 60 min later, WB PET/CT was taken using GE Discovery STE PET CT camera. Results: One patient had showed increased tracer both FES and FDG PET/CT uptake in primary lesion without any other metastasis. Six patients were postoperated, postchemotherapy, and postradiotherapy with biopsy-proven carcinoma breast having positive ER status of primary site. She came to our Centre to find out reoccurrence of tumor. Her FES PET/CT and FDG PET/CT both showed increased tracer uptake at multiple lesions. Three patients have postoperated, postchemotherapy, and postradiotherapy carcinoma breast. Their FES PET/CT shows no abnormal increased FES uptake while FDG PET/CT shows abnormal increased FDG uptake in multiple lesions. Conclusion: The correlative FES-PET/CT scan provides the functional ER status of breast cancer patients on WB basis more accurately than any other pathological assessments.
| PP 53:162810|| |
[11C]-Methionine positron emission tomography tracer: Synthesis and optimization of automated production in clinical usage
Department of Nuclear Medicine, SGPGIMS, Lucknow, India
Objective: Methionine (MET) is most widely used amino acid, is transported by the LAT1 amino acid transporter and it undergoes complex metabolism which is incorporated in proteins; therefore, increased uptake may reflect the metabolic needs of brain tumors. L-[methyl-11C] MET is widely used for the imaging of brain tumors (imaging of gliomas, astrocytomas, oligodendrogliomas, and other brain tumor), head and neck, lung, and breast cancer as well as lymphomas. Methods: In this study, we describe a fast, clean, and reproducible protocol for the production of L-[methyl-11C] MET (11C-MET) in multipurpose synthesizer (Sumitomo Heavy Industries MPS-100 synthesizer) is reported. An automated procedure was adopted for the synthesis of [11C] methyl iodide from [11C] CO2 and 11C-MET from [11C] methyl iodide and L-homocysteine thiolactone hydrochloride. Results: The synthesis was completed in 15 min after the end of bombardment with a yield 70 mCi with the radiochemical purity of >96%. Conclusion: Details of the automated synthesis technique along with the quality control testing results of the product will be presented.
| PP 54:134228|| |
Role of early dynamic positron emission tomography/computed tomography with 68Ga-PSMA-HBED-CC in patients with adenocarcinoma prostate
Gazala Perveen, Ravi Kant Gupta, Nishikant Avinash Damle, Madhavi Tripathi, Chandrasekhar Bal, Praveen Kumar, Rajeev Kumar, Geetanjali Arora, Meghana Prabhu, Prabhjot Singh1, Chandan Das2
Departments of Nuclear Medicine, 1Urology and 2Radiodiagnosis, AIIMS, New Delhi, India
Rationale: Prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA PET/CT) is widely used for imaging of prostate cancer (PC) nowadays. However, appearance of bladder activity many a times hampers lesion detection visa-a-vis primary as well as regional nodes. We aimed to assess if early dynamic PET/CT can be a potential solution to this issue. Methodology: A total of 15 biopsy-proven PC patients who were referred to our department for a 68Ga-PSMA PET/CT for staging/restaging were prospectively studied. Dynamic PET/CT was done with on table intravenous injection of 2–3 mCi (74–111 MBq) of the radiotracer. Dynamic images were acquired over the pelvis with a frame time of 1 min for 10 min. Static images of 2 min per bed position were acquired between 45 and 60 min after injection. A three-dimensional volume of interest was plotted on the primary lesion, involved nodes if any, pelvic bones at involved and uninvolved sites, gluteal muscles, and bladder. Key Results: Six patients were referred for staging and nine for restaging. Mean age of 15 patients was 66.7 years, median prostate-specific antigen level was 17.25 ng/ml (range 0.05–218), and mean Gleason's score was 8. All patients showed high target to nontarget ratio in the early dynamic images comparable to that seen on the delayed images in different sites (prostatic primary: n = 15 patients; lymph nodes: n = 10 patients; bone: n = 5 patients). All pathologic lesions showed tracer uptake within the first 3 min and reached maximum uptake during the dynamic study in last 3 min, indicating an increasing uptake pattern, whereas urinary bladder activity was insignificant within the first 3 min of dynamic imaging in all patients, reached maximum during last 2 min. Maximum standardized uptake value was significantly higher in primary lesions in the first 4 min compared to urinary bladder accumulation. Static images showed more tracer accumulation than dynamic images in primary, nodal, and bony lesions. However, all regional nodes seen on delayed static imaging also showed uptake on dynamic imaging. Research Highlights: Early dynamic imaging 68Ga-PSMA PET/CT can demarcate the primary tumor clearly due to nonaccumulation of bladder activity and appears to have comparable efficacy in detecting pelvic nodal sites as delayed imaging.
| PP 55:111323|| |
Targeting intravascular thrombosis using [99mtc]-DTPA-bis-c (RGDfK) as a single photon emission computed tomography imaging agent
Ankita Pandey, Ambika Jaswal, Jurgen Schulz1, Puja Panwar Hazari, Anil K. Mishra
Division of Cyclotron and Radiopharmaceutical Sciences, Institute of Nuclear Medicine and Allied Sciences, DRDO, New Delhi, India, 1University Bordeaux, INCIA, Talence, France
Rationale: Integrins have been proposed as promising molecular targets for diagnosis and therapy of multiple diseases. Integrin αIIbβ3 is expressed exclusively on platelets and plays critical role in hemostasis and intravascular thrombosis. Both αvβ3 and αIIBβ3 receptor ligands share a common RGD tripeptide binding sequence. We have previously demonstrated that [99mTc]-DTPA-bis-c(RGDfK) is an excellent scintigraphic agent for imaging of αvβ3 receptors being expressed in abundance in malignant glioma and melanoma cancer. In the present study, we describe the synthesis of [99mTc]-labeled DTPA-bis-c(RGDfK) conjugate and its preclinical evaluation in animal models of thrombosis. Methodology: DTPA-bis-c(RGDfK) was labeled with 99mTc with >95% radiolabeling efficiency. Mice models of pulmonary thromboembolism and ferric chloride-induced femoral artery thrombosis were established and thrombus was characterized using hematoxylin and eosin staining. [99mTc]-DTPA-bis-c(RGDfK) was injected intravenously in mice models of thrombosis, followed by single photon emission computed tomography (SPECT) imaging and biodistribution studies. Key Results: Biodistribution studies and SPECT imaging in pulmonary thromboembolism and ferric chloride-induced thrombosis in mice revealed significant accumulation of [99mTc]-labeled DTPA-bis-c(RGDfK) peptide in the thrombosed lungs and femoral artery along with moderate amount of nontarget accumulation in the liver and spleen. Research Highlights: 99mTc-DTPA-bis-c(RGDfK) peptide represents a promising radiotracer for the molecular imaging of intravascular thrombus. It showed high thrombus uptake with minimal off-target accumulation in the liver and spleen. The present study may provide a powerful diagnostic tool for the assessment of acute or chronic thrombosis in the clinics.
| Infection and Inflammation|| |
| PP 56:194927|| |
Role of technetium-99m dimercaptosuccinic acid scan as the initial investigative modality in atypical and recurrent urinary tract infection in children: “The top-down approach”
Arun Ravi John, A. G. Pandit, Anurag Jain, V. Shankar Raman, Braj Kishore, Abhinav Jaimini, K. P. Solanki, M. J. Jacob
Department of Nuclear Medicine, Army Hospital Research and Referral, New Delhi, India
Objectives: To study the role of technetium-99m dimercaptosuccinic acid (99mTc DMSA) scan in cases of recurrent urinary tract infection (UTI) and atypical UTI as a screening modality in pediatric age groups. Methodology: A total of 51 patients between 6 months and 12 years of age detected with recurrent or atypical UTI confirmed by urine culture along with a primary vesicoureteral reflux (VUR) detected on voiding cystourethrography (VCUG) performed 2–3 weeks after treatment (as per IAP/ISPN/AAP guidelines) were included in the study. 81 renal units with VUR was obtained from the recruited patients which was the sample size. The children recruited were subjected to a 99mTc DMSA scan 4–6 months after acute infection. The results of the study were tabulated into five groups with 1–5 grades of VUR obtained on VCUG as per the IRSC classification. Key Results: (a) The scarring rate according to the reflux of grades I, II, III, IV, and V were 0%, 33%, 50%, 90%, 77%, and 60%, respectively, with significant difference between the group of patients with VUR of grade I–III and the group with VUR IV–V (P< 0.05). (b) In addition, the study also found an association between severity of VUR and severity of scarring. High grades of reflux (VCUG grade IV and V) were significantly associated with severe scarring (Criteria by Monsour et al.) (P< 0.05). (c) High sensitivity (83%), high negative predictive value (78%), and relatively low likelihood ratio negative (0.26) of abnormalities on DMSA scan to detect the high-grade reflux (IV–V) were found. Research Highlights: The present study revealed that DMSA scan with a good degree of confidence can predict the presence high-grade reflux in pediatric age groups. Normal DMSA finding decreased the probability of finding the reflux of clinical significance on VCUG, supporting the strategy to perform VCUG only on patients with abnormal DMSA scans in children more than 6 months of age with recurrent UTI. This study gives further credence to the “top-down” approach advocated by NICE guidelines (UK) for UTI not only in cases of first febrile UTI but also in cases of recurrent/atypical UTI in pediatric age groups above 6 months of age.
| PP 57:134307|| |
Technetium-99m–Voriconazole: An in-house preparation as an antifungal imaging agent
Kanchan Palarwal, Priya Bhusari, Rakhee Vatsa, B. R. Mittal, Jaya Shukla, Anupriya Chhabra
Department of Nuclear Medicine, Post Graduate Institute of Medical Education and Research, Chandigarh, India
Rationale: Fungal infection poses a serious threat to individuals who are immune compromised. Histopathology and culture are invasive and still remain the gold standard for fungal infection detection. Voriconazole, a triazole, exhibits antifungal action by impairing the production of ergosterol in the fungal cell membrane. The present study aims to develop voriconazole as a potential radiopharmaceutical for imaging fungal infections. Methodology: Technetium-99m (Tc-99m) was used to radiolabel commercially available voriconazole via stannous reduction method. Voriconazole was labeled with 99mTcO4− (5–10 mCi) using with SnCl2 reduction method (reaction volume <1 ml). The pH of reaction mixture was varied from 2 to 8 and incubated at room temperature for 5–25 min. Quality control was performed using saline and acetone as mobile phase. Key Results: Greater than 98% radiolabeling yield was achieved by incubating 5 mCi of Tc-99m with 100 μg of voriconazole at 3.5–4.0 pH for 15–20 min at room temperature. Radiochemical purity of ~100% was achieved as observed in radio ITLC. Rf in saline and acetone were observed 0.7–0.8 and 0.0, respectively. Research Highlights: Voriconazole was successfully labeled with Tc-99m and can be used for noninvasive imaging of fungal infections.
| PP 58:161121|| |
18F-fluorodeoxyglucose positron emission tomography/computed tomography findings in Kikuchi disease mimicking lymphoma: Report of two patients
Sunita Sonavane, Gaurav Malhotra, China Naik, Kavita S. Joshi1, Ramesh Asopa
Radiation Medicine Centre, BARC, 1Department of Medicine, King Edward Memorial Hospital, Mumbai, Maharashtra, India
Rationale: Common etiologies for fever of unknown origin (FUO) include tuberculosis, lymphoma, etc. However, uncommon etiologies include Kikuchi–Fujimoto Disease (KFD)/Castleman's disease which are self-limiting necrotizing lymphadenitis. Recognition of this condition is crucial because it has excellent prognosis. Methodology: FUO cases evaluated by whole-body (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) scan was done 60 min after intravenous injection of 6–7 mCi of 18F-FDG, using a whole-body full-ring dedicated three-dimensional PET-CT scanner covering from vertex to mid-thigh region. Whole-body low-dose (50 mAs, 120 kVp) noncontrast CT scan was acquired for attenuation correction and anatomical co-localization. Images were reconstructed using standard iterative algorithm (RAMLA). Images were reformatted into transaxial, coronal, and sagittal views. Images were evaluated by qualitatively and semi-quantitatively. Key Results: Case 1: An 8-year-old male child presented with high grade fever of 4 months duration. On physical examination, the child had significant cervical lymphadenopathy and hepatosplenomegaly. FDG PET/CT scan revealed multiple hypermetabolic nodes including cervical, largest left supraclavicular (maximum standardized uptake value [SUVmax]: 10.0), mediastinal, largest anteroposterior window (SUVmax: 11.14), mesenteric, largest paracaval (SUVmax: 9.08), and multiple lesions in spleen (SUVmax: 14.89). Histopathology of cervical lymph node revealed features of Kikuchi disease, an uncommon, idiopathic disease, probably of autoimmune cause, with generalized lymphadenopathy. Follow-up FDG PET/CT after 3 months of corticosteroid therapy showed near-total structural and metabolic resolution of the disease. Case 2: A 29-year-old female presented with a history of persistent fever, severe debilitating malaise, and body ache with clinically localized left cervical adenopathy. Routine blood and urine investigations were not contributory and workup for tuberculosis or viral hepatitis and SLE was negative. FDG PET/CT revealed hypermetabolic left cervical adenopathy (SUVmax: 10.8). Biopsy from these showed features of Kikuchi disease. Research Highlights: FUO with lymphadenopathy is commonly due to infective etiology such as tuberculosis or malignant etiology such as lymphoma. Even though rare, Kikuchi–Fujimoto Disease should be one of the differential diagnoses for such a presentation. 18F FDG PET/CT despite being nonspecific is useful for choosing the approachable site for biopsy (mapping the disease burden) and in evaluating metabolic response as shown in one of the cases.
| PP 59:133554|| |
Correlation of 18F-fluorodeoxyglucose positron emission tomography with inflammatory markers in Takayasu disease
Julie Hephzibah, David Mathew, Nylla Shanthly, Regi Oommen
Department of Nuclear Medicine, Christian Medical College, Vellore, Tamil Nadu, India
Rationale: Takayasu disease is a primary systemic vasculitis of unknown etiology that affects large arteries. Inflammatory markers alone may not always be a sensitive parameter to assess disease activity. As 18F-fluorodeoxyglucose positron emission tomography (F18 FDG PET) is a metabolic imaging tool, a positive study with high FDG uptake could indicate severity of disease. Methodology: Retrospective analysis of data of patients diagnosed with Takayasu disease who were subjected to F18 FDG PETCT (n = 32) between 2014 and 2017 was done. Acute-phase reactants, erythrocyte sedimentation rate (ESR) >50mm/h and C-reactive protein (CRP) >6mg/L, were taken as active disease with positive PET which was defined as uptake in large arteries with a maximum standardized uptake value >2.5. Key Results: Among 32 patients who were studied, 27 were females and 5 males, age ranging from 15–52 years (median age in years 31). Among 11 positive PET studies, 10 (90.9%) patients had high ESR and or CRP (both ESR and CRP high in 8), and remaining patient had ESR and CRP low. In 21 PET-negative patients, 11 had low ESR and CRP (11/21, 52.4%). In the remaining 10 patients, both inflammatory markers were high in four patients and either ESR or CRP was high in six patients. In all 21/32 (65.6%) patients, PET findings were in agreement with inflammatory markers. Research Highlights: F18-FDG PET CT, a noninvasive diagnostic modality, is complementary to acute phase reactants in two-thirds of the patients for the evaluation of activity in Takayasu disease.
| Medical Physics|| |
| PP 60:043158|| |
National electrical manufacturers' association physical imaging performance characteristics of the whole-body discovery NM/CT 670: Our initial experience
Ashutosh Pandey, Meena Negi, Vandana Kumar Dhingra
All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India
E-mail: firstname.lastname@example.org, email@example.com
Rationale: National Electrical Manufacturers Association (NEMA)-based performance measurements have pervasive and routine importance in nuclear medicine imaging. It describes essential part of justification and appropriateness. Hence, the aim of this work was the assessment of the physical performance of Newly Installed Discovery NM/CT 670 system. Methodology: Physical imaging performance measurements of sensitivity, uniformity, spatial resolution, energy resolution, scatter fraction, spatial linearity, scan speed, count rate, collimator hole angulation, detector head shielding leakage, and centering of PHA window were obtained using NEMA 2012 methodology. Key Results: The centering of PHA windows peak was 140.14 Kev and 140.19 Kev. The energy resolution was 8.84 and 8.75 for detector one and two, respectively. Maximum count rate was 506 Kcts and 503 Kcts and sensitivity was 162 and 160 for detector one and two, respectively. Other performance value was in acceptable range according to acceptance limit of NEMA. Research Highlights: The Discovery NM/CT 670 (GE Healthcare) shows precise performance characteristics for all standard NEMA 2001/2007 with 2012 methodology. Furthermore, with the help of new reconstruction software tools, we can improve our results for better image quality without compromising diagnostic accuracy.
| PP 61:210801|| |
Investigating the role of intensity transformation function in high dynamic range bone scintigraphic image enhancement
Anil Kumar Pandey, Akshima Sharma, Vaishali, Arun Raj, Chandrasekhar Bal, Rakesh Kumar
Department of Nuclear Medicine, AIIMS, New Delhi, India
Rationale: The bone scintigraphic images exceeding the dynamic range of display system are difficult to display. The displayed images have very small bright and large dark areas in which most of the details are hidden. In this study, we have investigated the role of intensity transformation function in improving these kinds of images. Methodology: Forty high dynamic range bone scintigraphic images were processed using intensity transformation (IT) function. The IT function has two parameters: threshold and slope. Threshold equal to mean counts of the image and slope was varied from 1 to 20. In-house application program written in MATLAB R2013b was used to process images. Twenty output images for one input image were visually inspected by two nuclear medicine (NM) physicians to select diagnostic quality images. The standardized slope (value of slope parameter) that produced maximum numbers of diagnostic images was determined. They also rated the image quality of input and output images (at standardized slope) on scale 1–5 (1 being the poor and 5 being the excellent). Student's t-test was used to test the significance of difference between the mean image quality score assigned to input and processed images at significance level α = 0.05. Key Results: The application of intensity transformation functions with standardized slope parameter on high dynamic range bone scan images significantly improved the high dynamic range of bone scintigraphic image at P< 0.001 (with α = 0.05). The value of standardized slope parameter was found to be 8. Conclusion: The intensity transformation function has significant role in high dynamic range bone scintigraphic image enhancement.
| PP 62:105949|| |
Daily intrinsic quality control for performance evaluation of dual-headed gamma camera
Jisna Joshy, B. Surya, E. R. Radhakrishnan, I. V. Upadhya, F. R. Kingsley, Jephy Joseph, Raghi Jose, KK Kamaleswaran, Ajit Shinto
Department of Nuclear Medicine and PET CT, Kovai Medical Centre and Hospital, Coimbatore, Tamil Nadu, India
Aim: To evaluate the performance of dual-head gamma camera intrinsic uniformity test. Introduction: The intrinsic uniformity test is a part of the quality assurance program that ensures high standards of efficiency and reliability in the use of a gamma camera. Thus the changes in the performance of a gamma camera system can be avoided that might affect the interpretation of clinical studies. Materials Required: Point source (35 microCurie), lead mask, plastic sheet or absorbent sheet, source mounting for point source were the materials required. Methods: Intrinsic uniformity must be assessed daily and after each repair; it must be critically evaluated and any necessary action must be undertaken before using a gamma camera for patient imaging. Intrinsic uniformity quality control done from January to August were recorded. The integral and differential intrinsic uniformity test for both useful field of view and central field of view are done by placing a point source of 99m Tc in front of the detectors with removed collimators to measure the effect of source activity, source volume, source-to-camera distance, count rate, and correction matrix intrinsic uniformity. Intrinsic uniformity test has been performed as part of the acceptance testing of the Siemens Signature Series (Dual Head) single photon emission computed tomography system. The retrospective data compiled for January 2017–August 2017 will be presented in a graphical form, during the meeting.
| PP 63:111020|| |
Area monitoring for radiation surveillance
S. Nivetha, A. Ragavi, E. R. Radhakrishnan, I. V. Upadhya, F. R. Kingsley, Jephy Joseph, Raghi Jose, KK Kamaleswaran, Ajit Shinto
Department of Nuclear Medicine and PET CT, Kovai Medical Centre and Hospital, Coimbatore, Tamil Nadu, India
Introduction: Area monitoring is a quality indicator to evaluate radiation safety levels maintained in a nuclear medicine department. Theory and Principle: Radiation surveillance using radiation survey meter is performed to locate the radioactivity and to measure the level of radiation exposure rate at identified location controlled and uncontrolled areas. Radiation survey monitoring is good practice to achieve ALARA and provide safe working place for occupation workers as well as public. 1 mR/h is accepted limit for exposure rate is controlled areas such as positron emission tomography/computed tomography (PET CT), single photon emission computed tomography (SPECT) CT, radiopharmacy, fluorodeoxyglucose (FDG) dispensing and injection rooms. In uncontrolled areas such as reception and doctor's room, exposure levels should not be more than twice of the background. Materials Required: Survey meter (fluke) was the material used. Methods: Controlled areas for area monitoring were identified as radiopharmacy, FDG dispensing, FDG injection, SPECT injection, PET CT scanner, FDG waiting rooms, iodine ward, including decontaminated isolation rooms. Area monitoring in controlled and uncontrolled areas are monitored, in four corners and in center of the room, using “Fluke” survey meter. In controlled areas such as radiopharmacy and PET CT dispensing room, the place where the radiation worker is standing is also monitored. Uncontrolled areas were identified as corridor, NM reception, general waiting room, common console, technologist room. Observation: Radiation surveillance shows exposure rate in a diagnostic laboratory and therapeutic laboratory is within the prescribed limit. The data will be presented in the graphical format in the presentation, during the meeting. Conclusion: Area monitoring is a good quality indicator to verify the safe radiation levels in NM area.
| PP 64:112318|| |
Gamma scintigraphy evaluation of gastrointestinal physiology of animals exposed to hypobaric hypoxia condition simulated to 21,000 feet altitude
Braj Gaurav Sharma, Vipin Kumar, Harish Rawat, Ashok K. Salhan1, Aseem Bhatnagar
Department of Nuclear Medicine, Institute of Nuclear Medicine and Allied Science, DRDO, 1Defence Institute of Physiology and Allied Science, Delhi, India
Rationale: There are numerous problems of gastro-intestine associated with the hypobaric hypoxia (high altitude regions, e.g., Siachen Glacier). Quantified data about problems and exact mechanism behind the gastrointestinal (GI)-associated acute mountain sickness (AMS) are not studied yet. The present study was carried out to observe the changes in gastrointestinal transit time, histopathology of GI tract (GIT) and gastric acid secretions of animal at simulated high altitude conditions (335.28 mmHg absolute equivalents to a height of 6401 m/21,000 feet). Methodology: Twenty-four male Wistar rats were divided into two groups and four subgroups comprising of six rats in each groups. Group I animals was taken for noninvasive studies while the animals of Group II taken for invasive investigations. Radiolabeled compound (99mTc-sulfur colloids) was used as radiotracer to determine the GI transit rate of animals. Stomach contents of animals were collected to measure pH and levels of acid secretion. Histopathological analysis of gastrointestinal part was studied. Key Results: Colonic and gastric motility in hypoxia-induced animals was found slow as compared to control animals. The pH was increased significantly in hypoxia-induced group and level of acid secretion in stomach contents was found to be decreased. Mucosal inflammation in small intestine and large intestine found in the hypoxia-exposed group. Goblet cell decrease in the GIT of test group due to acute exposure to hypoxia while no significant changes come in stomach. Conclusion: It can be concluded after several sets of experiments that hypobaric hypoxia is the main contributor for the high altitude illness. Slowdown of gastrointestinal motility was assessed using scintigraphy method and verified with biodistribution study in animal model. Diminished pathophysiology of GI is also a part of AMS.
| PP 65:113600|| |
Comparison of quantitative parameters obtained using VPHD and Q. Clear reconstruction techniques available on Discovery IQ positron emission tomography system
Sneha Mithun, Ashish Kumar Jha, Ameya D. Puranik, Nilendu C. Purandare, Sneha Shah, Archi Agrawal, Venkatesh Rangarajan
Tata Memorial Hospital, Mumbai, Maharashtra, India
Rationale: The objective of the study was to compare and correlate maximum standardized uptake value (SUVmax) and total lesion glycolysis (TLG) obtained in set of patients by different image reconstruction techniques – VPHD and Q. Clear available with positron emission tomography/computed tomography (PET/CT) system Discovery IQ (D-IQ, GE Medical Systems, Milwaukee, WI) 5-ring detector configuration. Methodology: The study approved by Institutional ethics committee had total 29 patients (12 males, 17 females) included who underwent routine 18F-fluorodeoxyglucose (18F-FDG) PET/CT. Patients were administered with 5 MBq/kg body weight of 18F-FDG and study was performed in list mode after 1 h of administration at scan speed 60 s/bed. Images were reconstructed for 60 s as well as 45 s/bed using both reconstruction techniques. Image sets - 60secVPHD (VP60), 45secVPHD (VP45), 60secQ. Clear (QCl60), and 45secQ. Clear (QCl45) - were compared, lesions identified and volumetric SUVmax and TLG of identified lesions obtained by qualified nuclear medicine physician on all datasets. Absolute %difference in SUVmax and TLG were calculated for all sets. Wilcoxon Signed-Rank Test was performed for statistical analysis. Key Results: Mean, standard deviaton, minimum and maximum of SUVmax and TLG [Table 1], and absolute %difference in mean of SUVmax and TLG of all lesions [Table 2] are summarized. Two-tailed Wilcoxon signed-rank test was significant at P ≤ 0.01 for comparison of SUVmax between VP45 and QCl45 as well as VP60 and QCl60. The same was true for TLG. However, results were not significant at P ≤ 0.01 or P ≤ 0.05 for comparison between VP45 and VP60 and also QCl45 and QCl60. Research Highlights: The study shows that there is significant difference in SUVmax and TLG obtained by two reconstruction techniques (VPHD and Q. Clear) for same time/bed position. However, no significant difference in SUVmax and TLG is noted with respect to acquisition time (i.e., between 45 s and 60 s for same reconstruction technique) with either reconstruction techniques.
| PP 66:120620|| |
Analysis of induced radioactivity in the liquid radioactive waste in a medical cyclotron facility
Aruna Kaushik, Puja Panwar Hazari, Nitin Kumar, Sachin Sony, Swatantra, Pradeep Goswami, Sukhvir Singh, Anil K. Mishra
Institute of Nuclear Medicine and Allied Sciences, DRDO, Delhi, India
Rationale: The positron-emitting radionuclide 18F is the most common positron emission tomography (PET) radioisotope produced in the medical cyclotron. This involves bombarding the 18O target with accelerated protons that result in the generation of secondary neutrons. The accelerated charged particle and the secondary neutrons interaction with cyclotron parts may result in induction of radioactivity. The purpose of this study is to investigate the induced radioactive by-products of the medical cyclotron facility installed at INMAS and discuss its implication for waste disposal management. Methodology: INMAS has medical cyclotron (PETtrace system, M/s GE Medical Systems) that can accelerate negatively charged hydrogen ions (H −) to 16.5 MeV or negatively charged deuterium ions to 8.4 MeV. The parts of the cyclotron that need to be replaced during maintenance and the liquid radioactive waste that originates during routine operation of the cyclotron were analyzed by gamma-ray spectrometry and beta particle counting. The amount of radioactivity in each sample was compared with the exempt levels of radioisotope as recommended by International Atomic Energy Agency. Key Results: A number of short-lived and long-lived radioisotopes were found to be present in the replaced cyclotron parts and liquid radioactive waste. The samples that contained radioactivity less than the exempt levels were recommended for disposal as ordinary waste. Other samples were stored in the cyclotron vault till their activity becomes less than the exempt levels.
| PP 67:143602|| |
Standardization of uptake calculation in whole-body sweep with different scan speeds using gamma camera
K. Biju, Sushama Awasare, Nawab Singh Baghel, Sandip Basu
Radiation Medicine Centre, BARC, Mumbai, Maharashtra, India
Introduction: Conventionally, thyroid uptake is calculated using uptake probe in nuclear medicine centers, but currently, radioiodine uptake is also calculated using gamma camera as an alternative method to avoid the need of thyroid uptake probe. Uptake is calculated on gamma camera by acquiring static image of thyroid, whereas whole-body sweep is a routine practice for radioiodine imaging. If there is a method by which the uptake is calculated using whole-body imaging, the need for static images along with whole-body imaging can be eliminated. Aims and Objectives: To standardize a method for uptake calculation in whole-body imaging with various scan speeds on gamma camera. Materials and Methods: Whole-body scan of 25 μCi 131I capsule in a lucite phantom was carried out on Siemens (Symbia) dual head gamma camera with high-energy collimator. The imaging was done with different scan speeds of 4 cm/min, 5 cm/min, 10 cm/min, 15 cm/min, 20 cm/min, and 30 cm/min. Total 10 sets of scans of different speeds have been performed. Analysis was done by drawing region of interest around the capsule in the images with different speeds to obtain counts. Decay correction was applied on capsule activity and counts/μCi was calculated. Graph of speed versus counts/μCi was plotted and curve was best fitted to obtain the equation between speed and counts/μCi. Thyroid uptake was calculated in 20 patients by thyroid probe and gamma camera-based method. The data were analyzed to find the correlation between both the methods. Results: Empirical relation was obtained as counts/μCi = 3631/speed for the gamma camera. The calculated uptake using this empirical formula is compared with uptake calculated using thyroid uptake probe. Good correlation was observed between both data with correlation coefficient r >0.9. Conclusion: Standard count estimation in whole-body scan for different scan speed is very tedious procedure as it will be different for different scan speed. Using this empirical formula, the standard counts/μCi can be estimated from any speed scan. This requires only one time standards capsule whole-body scan, which will not only save time but also relieve from limitation of carrying out whole-body imaging with fixed scan speed for uptake calculation.
| PP 68:161039|| |
Can we reduce the whole-body exposure from 18F-fluorodeoxyglucose
Om Prakash, Rasna Tiwari
The Gujarat Cancer and Research Institute, New Civil Campus, Ahmedabad, Gujarat, India
Introduction: As we know that positron emission tomography (PET)-computed tomography scan provides both anatomical and physiological information in single study, but this study has raised the issue of more radiation exposure to nuclear medicine professionals. PET emitters have more energetic gamma photons (511 keV). Hence, it needs more protective materials. Aims: A simple-step reduction technique can reduce the whole-body exposure to nuclear medicine professional, a quantitative study analysis. Materials and Methods: This study conducted on more than 200 patients. Fifty percent of them had been injected directly on injection chair, and other 50% injected behind the wall. There was a small window on wall where patient put their intravenous cannulated hand from other side and technologist inject the 18F-fluorodeoxyglucose from other side of wall. In this process, all radiation safety accessories were used. Measuring instrument was personal dust monitor117. Results: When the patient injected directly on injection table the chest dose was 4.2 ± 1.2 μsv/patient and wrist got 13.5 ± 1.9 μsv/patient. When the same dose given to another patient from behind the wall, the wrist radiation dose reduced to 4.1 ± 1.0 μsv/patient and chest dose reduced to 4.58 ± 0.8 μsv/7 patients. Discussion: The result shows that our wrist and chest get maximum exposure in withdrawing and injection the dose. When we keep ourselves behind the wall and lead partition, our body gets minimum radiation dose because wall thickness and distance from the patient. Conclusion: This process is very safe and reduces the whole-body radiation exposure with less chances of contamination of work surface area.
| PP 69:174647|| |
An investigation of the effect of shape and size of two-dimensional median filter on the noise removal from iodine-131 scintigraphic image
Anil Kumar Pandey, Kartik Saroha, Girish Kumar Parida, S. T. Arun Raj, C. S. Bal, Rakesh Kumar
Department of Nuclear Medicine, All India Institute of Medical Sciences, New Delhi, India
Rationale: The two-dimensional median filter removes the noise and also retains better edge information in comparison to linear filter. The aim of the study was to investigate the effect of shape and size of the median filter on the noise removal from iodine-131 scintigraphic image. Methodology: Fifty iodine-131 noisy scintigraphic images were processed using in-house MATLAB application program. The application can process input image with two-dimensional median filter having square and cross shape and each shape has mask size equal to 3, 5, 7, and 9 pixels. Two nuclear medicine physicians evaluated the quality of input and its corresponding output images (i.e., total 450 image; 50 input images and 400 processed images). They assigned score to each image on the scale 1–5, 1 being the lowest and 5 being the highest quality based on the noise removal, smoothness, and edge information available in the image. Student's t-test was applied to find the significant difference in the image quality (at alpha = 0.05) between the processed images with square-shaped and cross-shaped mask with same pixel width. Key Results: Application of median filter improved the image quality. The degree of smoothness increased with increase of size of filter. The quality of images processed with cross-shaped two-dimensional median filter was found to be better and was clinically preferred over the square-shaped mask of same size at P< 0.001. Research Highlights: Images processed with cross-shaped two-dimensional median filter were found to better and clinically preferred over that of square-shaped.
| PP 70:184835|| |
Single photon emission computed tomography image reconstruction by development and validation of filtered back projection algorithm for research purposes
Umesh Yadav, A. K. Pandey, Rakesh Kumar, Chetan D. Patel
Department of Nuclear Medicine, AIIMS, New Delhi, India
Aim and Objective: The aim of the study was to develop personal computer (PC) software to reconstruct an image from parallel projections based on filtered back projection techniques and to compare the reconstructed image by newly developed software with the reconstructed image of the same dataset with vendor provided gamma camera processing workstation. Materials and Methods: Computer program was implemented on the PC using MATLAB R2013b. To verify the program, projections from various angle of a known object (Shepp–Logan phantom, a widely used synthetic image designed to simulate the absorption of major areas of the brain, including small tumors) was obtained using Radon transform. The filtered back-projected image was obtained as follows:
- Acquire projection profiles in object space at N projection angles, θ = 1, 2, …, N
- Computing the one-dimensional (1-D) Fourier transform of each projection
- Multiplying each Fourier transform by the filter function (for example, Ramp filter, Hamming filter, Hann filter, and Butterworth filter)
- Obtain the inverse 1-D Fourier transform of each resulting filtered transform
- Integrate all the 1-D inverse transforms from step 3.
The program was also verified by real projection data obtained with single photon emission computed tomography gamma cameras (Siemens NM and GE Healthcare). An interface function was written to read the projection data from DICOM files. The filtered back-projected image was obtained following the method as mentioned before. The reconstructed image from our developed program was compared with the image reconstructed by the vendor's software. Results: The computer program accurately reconstructed the phantom and patients image. However, the image quality of the reconstructed image with our program is not as sharp as the image quality of reconstructed image with vendor's software. Conclusion: The final image quality of our in-house developed software's image reconstruction and vendor provided workstation's images were comparable. Our results established optimum reconstruction parameters by FBP technique and Butterworth filter with cutoff frequency (0.8) and order value (5) in SIEMENS system and critical frequency (0.9) and power (5) in GE Healthcare system.
| PP 71:233717|| |
Dosimetry of 99mTc-labeled phosphonates
Aruna Kaushik, Puja Panwar Hazari, Anil K. Mishra
Institute of Nuclear Medicine and Allied Sciences, Timarpur, Delhi, India
Rationale: Bone scintigraphy is the most commonly performed nuclear medicine procedure. The paper aims at comparison of internal doses to various organs from 99mTc-labeled methylene diphosphonate (MDP) and other 99mTc-labeled pyrophosphonates. Methodology: The biodistribution studies of compounds 99mTc-MDP, 99mTc-EDTMP, 99mTc-CDTMP, and 99mTc-DTPMP were performed in Balb-c mice following intravenous injection. The activity in the target organs were measured at an interval of 1, 4, and 24 h. The residence time was estimated in heart, lungs, liver, spleen, kidneys, stomach, intestines, brain, muscles, and bone. OLINDA software was used to estimate organ and whole-body doses. The values were extrapolated to human beings. Results: The kidneys and the bladder received maximum dose.
| PP 72:183136|| |
Development of 141Ce point source as a surrogate for 99mTc-based markers in routine nuclear medicine imaging
Basant Malpani, Sutapa Rakshit, Sanjay Kumar Saxena, Yogendra Kumar, Biju Menon, Nawab Singh Baghel, Sharmila Banerjee, Ashutosh Dash
Radiation Medicine Centre and Isotope Applications and Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra, India
Rationale: The use of a marker to identify a thyroid nodule in a thyroid scan and to identify whether there is any retrosternal extension of the gland is quite common. Nuclear medicine images being functional typically show the organs/diseases being imaged as bright spots with no indication of the rest of anatomy. Therefore, in many nuclear medicine procedures, a radioactive marker is required to be placed to obtain fiducial relationship in the image space between objects of interest. Commonly, a point source of 99mTc is constructed by dropping very small quantities of any 99mTc-based radiopharmaceutical in a needle cap or syringe and packed with cotton plug to prevent contamination. This is an extra procedure necessitating care during such dispensing, as there is a likely hood of spills and contamination. Moreover, such sources are required to be prepared freshly, daily, or when needed as 99mTc decays rapidly. We herein considered developing a point source of 141Ce that can be used over a longer period of time and discuss its physical characteristics and scope of application. Methods: The physical characteristics of 141Ce make it an ideal surrogate for 99mTc in the given application. 141Ce has a half-life of 32.5 days and decays by beta-particle emission that is associated with a gamma of 145 KeV with fractional abundance of 0.45. The 145 KeV gamma of 141Ce is very close to the 140 KeV gamma emission of 99mTc and thus allows it to be replaced with 99mTc as a marker when using NaI(Tl)-based gamma camera. Reactor route was applied to produce 141Ce. Neutron irradiations of natural Ce(SO4)2.4 H2O targets in Dhruva Nuclear Reactor of our Institute was tested at different neutron fluxes for different time periods and allowed to decay for different durations to eliminate the presence of relatively shorter lived radionuclidic impurities such as 137Ce, 139Ce, and 143Ce. The salt was then solubilized in H2 SO4 to make aliquots and processed to be packed in very thin titanium capsules. The flux of gamma rays from a source of 1.5 mCi of 141Ce roughly corresponded to 0.7 mCi of 99mTc under a gamma camera. The capsule (about 10 mm in length and 5 mm in diameter was grooved one the one end and was comfortably screwed into a pen-shaped receptor for fixing and ease of use/replacement. Results and Discussion: We demonstrate the use and application of 141Ce as a radioactive marker that can replace 99mTc-based markers. The tiny capsule can be replaced in two-three months given the physical half-life of 141Ce and would be easy for transportation to any nuclear medicine center. It can also be used to evaluate intrinsic uniformity of the gamma camera when kept at an appropriate distance from the face of the detector. It can solve the frequent need to prepare point sources in a busy nuclear medicine department.
| PP 73:203339|| |
Intraoperative gamma probe bid specification
Sachin Tayal, Arun Gandhi
Kailash Cancer Hospital and Research Centre, Vadodara, Gujarat, India
Rationale: With the advent of oncological practices, gamma probes are not only becoming a boon to Nuclear Medicine Department but great possession for the Institute also. With single readout module and various gamma probes of different dimensions, it fulfills all the needs of pre- and post-operative detection as well as percutaneous localization of sentinel node/nodes in major clinical fields. The successful identification of sentinel nodes during the surgery has been shown to be determined not only by the surgeon skills but also by the performance of the sentinel probe and in particular, its sensitivity, spatial resolution, angular resolution and side shielding. Methodology: A comparison of physical performance parameters of available models of gamma probes was done to provide guidelines on bid specification for intraoperative gamma probes. Key Results: The article helps in purchasing process of intraoperative gamma probes by presenting a summary of parameters for bid specification with a major concern to its requirement of quality control frequency and response of service provider in case of emergency. Second, as the handheld gamma probe is moved rapidly and used in various positions, special care should be taken into consideration regarding the ergonomics and design features as the tough environment raises the probability of probe failure.. Research Highlights: Bid specification of intraoperative gamma probe.
| PP 74:230750|| |
Role of nuclear medicine technologist in radiation safety
Abhinav Baranwal, Satyawati Deshwal, Dhananjay Kumar Singh, Shashwat Verma
Department of Nuclear Medicine, Dr RMLIMS, Lucknow, Uttar Pradesh, India
Introduction: Role of nuclear medicine technologist to provide safe and effective patient care and radiation protection. Objective: The aims of our study were to minimize and control the radiation exposure and exposure rate of radiation worker, general public, and the environment. Methodology: To follow the rule of “ALARA,” radioactive source should be properly shielded, equipment such as GM counter, pancake device calibrated regularly for better detection of radiation, other materials such as adsorbent sheet, gloves, tong, test tube, shoe cover, and red tape for caution sign should be kept. Log book for record maintenance and sign boards for accident precautions were used. Chart of decontamination steps should be pasted in risk zones. In nuclear medicine department (NM Dept.), patient becomes the source of radiation; proper communication made with patient about radiation exposure to other people and maintaining time, distance, and shielding. SPECT-CT in oncology is a diagnostic tool of follow-up of various oncology indication, 99mTc-labeled radiopharmaceuticals decays by emitting radiation results in extra amount of radiations to radiation worker in NM Dept. We are performing around 20 cases per day. Efforts have been applied such as rotational duty, personal monitoring devices, i.e., to minimize radiation exposure, so that prescribed limit not crossed 20 mSv per annum. Conclusion: With better management and good practices of NM techniques, anxiety to work in the high exposure area gets reduced due to low radiation exposure.
| PP 75:170025|| |
Deployment of 22Na point source for daily quality control in positron emission tomography scanners
Basant Malpani, Sutapa Rakshit, Sanjay Kumar Saxena, Yogendra Kumar, Nawab Singh Baghel, Ashutosh Dash, Sharmila Banerjee
Radiation Medicine Centre and Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra, India
Rationale: The quality control (QC) and calibration of a positron emission tomography (PET) scanner include detector and electronic characterizations such as adjustment of PMT gain, definition of crystal and energy maps and coincidence timing calibration. Briefly, the crystal map converts the analog position of the detected event to a specific crystal within the block detector, while the coincidence timing calibration adjusts for timing delays, so events from each block are time stamped equivalently. These characterizations are applied to the PET data during acquisition. Daily QC check/calibration of a PET scanner is performed using a point source of either 68Ge-68Ga or a 22Na, both of which emit a positron and therefore annihilation radiation. The PET Scanner detectors are used to detect and measure the intensity of the annihilation photons in coincidence mode. 68Ge-68Ga and 22Na are preferred isotopes as they have a reasonable long half-life, but the is later more preferred because of a half-life of 2.6 years as compared to 276 days for 68Ge. At present most PET scanners employ an imported pencil source of 22Na that is mounted atop a holder to perform these scan. Our aim was to indigenously develop such a source and test its employability for daily QC of PET scanner. We herein discuss its physical characteristics and scope of application. Methods: Cyclotron produced Na-22 radiotracer was originally procured from an overseas supplier and the same was available in our Division as sodium chloride solution. It was tested for radionuclidic impurity by HPGe gamma spectrometry. About 3 mm long 22Na point source was prepared by incorporation of 22Na in a thin ionogenic membrane under optimized experimental conditions, the details of which are being communicated elsewhere. Radioactive membrane was then introduced within thin stainless steel capsule, which was attached to a stainless steel cylindrical rod. This indigenously prepared 22Na source of about 0.74 MBq strength was subjected for evaluation in our studies. PET scan performed under identical conditions for the imported 22Na source as well as indigenously produced source ware compared for sensitivity and compactness of the point source. Results and Discussion: We demonstrate the use and application of 22Na pin source using our Philips Gemini TOF PET-computed tomography system. The compactness of our indigenously produced pencil source is adequate to allow it to be used for daily calibrations and QC checks.
| PP 76:232144|| |
Precautions taken to minimize the risk from radiation accident
Md. Shakeel, Dhananjay Kumar Singh
Dr. Ram Manohar Lohia Institute of Medical Sciences, Lucknow, Uttar Pradesh, India
Rationale: Working in nuclear medicine department required a very careful handling of radioactive materials by taking all precautions and efforts to prevent any radiation accident the response to this accident is defined and a workout plan is adopted as a standard procedure. Methods: To minimize the radiation dose from the accident area, a standard method is adopted by all the workers and the technologist mock drill, educational seminars, training sessions are performed by RSO provided potassium iodide pills to affected person, make a contamination kit, copies of important documents spot. Key Result: After performing 5 mock drills and 10 educational seminars on radiation protection against the radiation accident, we observe that it is very beneficial among the radiation and non-radiation worker in nuclear medicine department. Research Highlights: We minimize the radiation accidental exposure risk for public and radiation workers by various educational programs.
| PP 77:110502|| |
Calibration factor values evaluation as a quality indicator from positron emission tomography-computed tomography daily quality control reports
R. Kowsalya, M. Afra Thagym, E. R. Radhakrishnan, I. V. Upadhya, F. R. Kingsley, Jephy Joseph, Raghi Jose, KK Kamaleswaran, Ajit Shinto
Department of Nuclear Medicine and PET CT, Kovai Medical Centre and Hospital, Coimbatore, Tamil Nadu, India
Aim: To compare daily calibration factor (ECF) values over the period of time and evaluate the performance of positron emission tomography-computed tomography (PET CT) system. Introduction: The ECF is a numeric value used to convert non quantitative PET images (counts/pixels/s) to quantitative images (Bq/ml). An accurate ECF is a necessary prerequisite quantitative region of interest and SUV. Materials and Methods: The ECF values obtained during normalization by scanning radioactive source, usually the Ge 68 solid phantom is slided into the adapter, provided with the Biograph system bearing a known assay date, assay time, activity and value. It is entered in an appropriate field of the normalization protocol. On system startup, the ECF value is verified by a software utility. If the ECF value is within the acceptable range for the gantry model, no messages are displayed and the system starts up normally. The typical ECF range is 2.59e+007 Bq/ml (minimum) and 3.6e+007 Bq/ml (maximum). The current ECF value, the typical ECF range, and the gantry model will be presented in the graphical format for the review of PET CT system performance. Conclusion: The ECF is a good quality indicator to evaluate the daily performance of PET CT system.
| PP 78:154703|| |
Development of cyclotron solid target removal assembly and estimation of radiation exposure in removal process
Kanchan Kushwaha1,2, Pravind Maletha1, Rahul Kashid1, Sunil Kamble3, Jyothish Babu3, Kavindra Pathak3, N. K. Prasad3, Manish Kumar3, T. K. Saha3, S. C. Gadkari3, Sharmila Banerjee1,2
1Radiation Medicine Center, Bhabha Atomic Research Center, 3Division of Technical Physics, Bhabha Atomic Research Center, 2Homi Bhabha National Institute, Bhabha Atomic Research Center, Mumbai, Maharashtra, India
Rationale: Solid target irradiation facility in medical cyclotron has gained more importance due to production of medically useful radioisotopes, viz., 64Cu, 111In, 89Zr, etc. A solid target assembly has been developed in-house to utilize at the existing PET trace medical cyclotron facility. Among the several challenges faced in the development of solid target assembly, the issue of safe transfer of the target after irradiation with minimum radiation exposure and contamination to the individual was a challenging requirement. To meet this need, a target removal assembly has been designed and tested. Methodology: The irradiated target needs to be transferred from solid target assembly to hot cell for chemical processing. Target base plate removal assembly was designed, fabricated, and assembled to drop the target base plate (25 mm diameter, 2 mm thick gold-plated copper disk with target material centrally electroplated) from solid target assembly to lead pot precisely and safely. The irradiated target along with lead pot is to be taken out of the cyclotron vault and transferred to hot cell manually. The radiation dose received by the individual during above transfer was estimated theatrically for 3.2 μAh proton beam irradiation on natural Ni electroplated target base plate. Key Results: Target base plate removal assembly was tested and found to be compatible with solid target assembly. The complete process may be performed within 5 min and total estimated radiation doses were around 0.35 μSv. Research Highlights: Target base plate removal assembly was successfully developed and tested and found satisfactory, with radiation exposures within acceptable limit.
| Women in Nuclear Medicine and Miscellaneous|| |
| PP 79:160258|| |
Cation selectivity of synthetic ion channels: An approach for mimicking biological channels
Sangeeta Negi, Awadhesh Prasad, Amita Chandra
Department of Physics and Astrophysics, University of Delhi, Delhi, India
Synthetic ion-channels, created by swift heavy ion bombardment (250 MeV Kr ions at a fluence of 4 × 106/cm2) followed by chemical etching (using 1 M NaOH) of polymeric membrane (polyethylene terephthalate), have interesting properties of ion selection and ion current fluctuation. These features are found to mimic biological channels. Polymeric membrane with ion-channels when used as an interface between two adjacent aqueous electrolytes (sodium and potassium), acts as anion selective barrier and regulates transportation of ions through it. The selectivity and transportation of Na + and K + ions through these channels depend on the channel's size, shape and external driving force such as concentration, applied voltage, membrane potential and ions' size. By tuning these parameters, voltage-gated sodium and potassium ion channels can be functionalized which can mimic the excitable cell membrane. These channels exhibit “opening” and “closing” with applied potential referred to as “high” and “low” conduction states, respectively. The nonlinear dynamical behavior of this system can predict its future application as ionic switches and ionic flip-flops.
| PP 80:132715|| |
Adulteration of mercury in skin-whitening creams: A nephrotoxic agent
Mohd Mazhar, S. S. Agrawal
Delhi Pharmaceutical Sciences and Research University, New Delhi, India
Rationale: Mercury is a neurotoxin which is used in the formulation of many cosmetics. When such cosmetics are used by pregnant woman, there are serious pathological manifestations in the fetus. It can also harm those children who are on breastfeeds and whose mothers are using these mercurial cosmetics. Such products are used on daily basis and after absorption through the skin mercury gets accumulated in kidney and other organ system. Methodology: Samples of mercury are prepared by CETAC Technologies of the USA, wherein the method used by Clarke et al. for mercury estimation was used. Samples are analyzed and compared with standard curve by 200 series Atomic Absorption with model VGA-77 (Vapour Generation Accessory) made by Agilent Technologies. Key Results: Mercury was detected in all the samples in the range of 0.004556 ppm (Skinshine Cream) to 0.009 ppm (Vaseline – menface Anti spot) as total mercury. Research Highlights: To promote the cosmotovigilance in India. Attention must be paid to monitor the presence of mercury in cosmeceuticals and for its truthfulness in their labeling on the wrappers. Regulatory agencies must frame the rules and regulations to have a control on the mercury content. There is no uniformity for mercury limits for such products by WHO, FDA, and DCGI.
| PP 81:232300|| |
Three-dimensional drug printing: A revolution in pharmaceutical science
Ubaid Tariq, Mir Javid Iqbal2
Delhi Pharmaceutical Science and Research University, New Delhi, India
In three-dimensional (3D) printing, objects are made by fusing or depositing materials in successive layers laid down under computer control. These objects can be of almost any shape or geometry and are produced from a 3D model as defined in a computer-aided design. Since the inception of 3D printing in 1984, it has evolved immensely and has been used in many fields including medicine, architecture and more recently in pharmaceutical manufacturing. From laboratory-grown organs to drug delivery devices, 3D printing is advancing rapidly, and in the future course of time, it is going to transform and change the way we live and work. 3D printing in pharmaceuticals has been used to produce many novel dosage forms such as microcapsules, complex drug-release profiles, nanosuspensions, and multilayered drug delivery devices. From industrial point of view, it also offers important advantages such as cost-effectiveness, increased productivity, democratization of design and manufacturing, and enhanced collaboration. Keeping in view the recent approval given by the USFDA to the first 3D-printed antiepileptic drug, the focus has now shifted to the personalized medicine as it offers an important benefit to patients who need medications that have narrow therapeutic indices or a higher predilection to be influenced by genetic polymorphisms. 3D printer is now seen as a valuable, efficient and economical tool to manufacture individualized medications, tailored to specific patients based on their needs and thereby change the future of pharmacy practice in general and pharmaceutical care in particular.