Spectrum of single photon emission computed tomography/computed tomography findings in patients with parathyroid adenomas :Dhritiman Chakraborty, Bhagwant Rai Mittal, Chidambaram Natrajan Balasubramanian Harisankar, Anish Bhattacharya, Sanjay Bhadada, Indian Journal of Nuclear Medicine

PICTORIAL ESSAY
Year : 2011 | Volume : 26 | Issue : 1 | Page : 52--55

Spectrum of single photon emission computed tomography/computed tomography findings in patients with parathyroid adenomas

Dhritiman Chakraborty¹, Bhagwant Rai Mittal¹, Chidambaram Natrajan Balasubramanian Harisankar¹, Anish Bhattacharya¹, Sanjay Bhadada²,
¹ Department of Nuclear Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh, India
² Department of Endocrinology, Postgraduate Institute of Medical Education and Research, Chandigarh, India

Correspondence Address:
Bhagwant Rai Mittal
Professor and Head, Department of Nuclear Medicine, PGIMER, Chandigarh - 160 012
India

Abstract

Primary hyperparathyroidism results from excessive parathyroid hormone secretion. Approximately 85% of all cases of primary hyperparathyroidism are caused by a single parathyroid adenoma; 10-15% of the cases are caused by parathyroid hyperplasia. Parathyroid carcinoma accounts for approximately 3-4% of cases of primary disease. Technetium-99m-sestamibi (MIBI), the current scintigraphic procedure of choice for preoperative parathyroid localization, can be performed in various ways. The «DQ»single-isotope, double-phase technique«DQ» is based on the fact that MIBI washes out more rapidly from the thyroid than from abnormal parathyroid tissue. However, not all parathyroid lesions retain MIBI and not all thyroid tissue washes out quickly, and subtraction imaging is helpful. Single photon emission computed tomography (SPECT) provides information for localizing parathyroid lesions, differentiating thyroid from parathyroid lesions, and detecting and localizing ectopic parathyroid lesions. Addition of CT with SPECT improves the sensitivity. This pictorial assay demonstrates various SPECT/CT patterns observed in parathyroid scintigraphy.

How to cite this article:
Chakraborty D, Mittal BR, Harisankar CB, Bhattacharya A, Bhadada S. Spectrum of single photon emission computed tomography/computed tomography findings in patients with parathyroid adenomas.Indian J Nucl Med 2011;26:52-55

How to cite this URL:
Chakraborty D, Mittal BR, Harisankar CB, Bhattacharya A, Bhadada S. Spectrum of single photon emission computed tomography/computed tomography findings in patients with parathyroid adenomas. Indian J Nucl Med [serial online] 2011 [cited 2023 Mar 31 ];26:52-55
Available from: https://www.ijnm.in/text.asp?2011/26/1/52/84618

Full Text

Introduction

The parathyroid glands develop during the sixth week of gestation. The superior glands develop from the fourth brachial pouch and the inferior parathyroid glands develop from the third. Even though there are typically four parathyroid glands, approximately 10% of individuals have between five and seven glands, known as supernumerary parathyroid glands, and 2-3% of individuals have fewer than four glands. The location of the superior parathyroid glands is fairly constant. They are found at the junction of upper and middle third of thyroid gland, posterolateral to the cricothyroid junction in majority of the population. Occasionally, the superior gland may remain undescended near the hyoid bone, along the pharyngeal musculature described as a parapharyngeus, or anywhere along its route of descent adjacent to the carotid sheath. Rarely, they are intrathyroidal or retroesophageal. The inferior parathyroid glands have a more varied anatomy and are more commonly found in ectopic sites. They can be found anywhere between the aortic bifurcation to the mediastinum. The most common ectopic location of the inferior parathyroid gland is within the thymic capsule or the superior mediastinum. [1] [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8] and [Figure 9].{Figure 1}{Figure 2}{Figure 3}{Figure 4}{Figure 5}{Figure 6}{Figure 7}{Figure 8}{Figure 9}

Primary hyperparathyroidism is characterized by the autonomous production of parathyroid hormone, resulting in hypercalcemia. It affects 1 in 500 women and 1 in 2000 men annually. [2] It occurs 2-3 times more frequently in women than in men. Hyperparathyroidism peaks in incidence in the fourth and ﬁfth decades of life but can occur in young children and the elderly as well. [3] It is a severe, symptomatic disorder with skeletal, muscular and renal manifestations at a young age. [4],[5] Normocalcemia is observed more often with frequency ranging from 50% in an earlier report [6] to 14% observed in a recent study. [5] Single adenoma is the most frequent etiology of primary hyperparathyroidism. Surgical treatment of hyperparathyroidism is successful in 95% of patients undergoing initial neck exploration. [7] Failure to find the parathyroidal lesion may be related to ectopia and anatomic variations in the location of the tumor. So far, the majority of parathyroid surgeons have held the consensus that preoperative localization studies are not indicated at initial exploration. However, this remains controversial. More recently, the better availability of preoperative parathyroid imaging techniques have made possible minimally invasive surgery, including unilateral neck exploration under local anesthesia [8],[9] and endoscopic parathyroidectomy through a very small incision. [10] Accurate preoperative localization and intraoperative guidance are required to enable selective minimal surgery and to reduce the operative failure rate. [11] Moreover, repeated exploration is associated with a higher rate of complications, including recurrent laryngeal nerve paralysis and hypoparathyroidism. [12]

Anatomic imaging modalities including ultrasonography, computed tomography (CT), and magnetic resonance imaging (MRI) have a relatively low sensitivity for detection of parathyroid adenomas. [13] Single-tracer dual-phase or the double-tracer subtraction parathyroid scintigraphy techniques provide high-quality imaging and reproducible scintigraphic ﬁndings. The previously used imaging approach combining Tl-201 and Tc99m subtraction scintigraphy showed only 45-75% sensitivity. Technetium-99m-MIBI scintigraphy has a higher target-to-background ratio and addition of single photon emission computed tomography (SPECT) improves the sensitivity to 90%. [14] Use of SPECT/CT helps to localize the ectopic parathyroid tissue. A combination of neck ultrasound and SPECT/CT has been shown to have incremental value over either technique alone and allows for selection of patients for minimally invasive parathyroid surgery. [15]

References

1	Shaha AR. Parathyroid re-exploration. Otolaryngol Clin North Am 2004;37:833-43.
2	Clark OH. Surgical treatment of primary hyperparathyroidism. Adv Endocrinol Metab 1995;6:1-16.
3	Bilezikian JP, Silverberg SJ. Clinical practice. Asymptomatic primary hyperparathyroidism. N Engl J Med 2004;350:1746-51.
4	Mishra SK, Agarwal G, Kar DK, Gupta SK, Mithal A, Rastad J. Unique clinical characteristics of primary hyperparathyroidism in India. Br J Surg. 2001;88:708-14.
5	Bhansali A, Masoodi SR, Reddy KS, Behera A, Radotra BD, Mittal BR, et al. Primary hyperparathyroidism in north India: A description of 52 cases. Ann Saudi Med 2005;25:29-35.
6	Harinarayan CV, Gupta N, Kochupillai N. Vitamin D status in primary hyperparathyroidism in India. Clin Endocrinol (Oxf) 1995;43:351-8.
7	Shaha AR, Jaffe BM. Cervical exploration for primary hyperparathyroidism. J Surg Onco 1993;52:14-7.
8	Irvin GL, Solorzano CC, Carneiro DM. Quick intraoperative parathyroid hormone assay: Surgical adjunct to allow limited parathyroidectomy, improve success rate, and predict outcome. World J Surg 2004;28:1287-92.
9	Udelsman R. Six hundred fifty-six consecutive explorations for primary hyperparathyroidism. Ann Surg 2002;235:665-70.
10	Cougard P, Goudet P, Bilosi M, Peschaud F. Videoendoscopic approach for parathyroid adenomas: Results of a prospective study of 100 patients. Ann Chir 2001;126:314-9.
11	Howe JR. Minimally invasive parathyroid surgery. Surg Clin North Am 2000;80:1399-426.
12	Jarhult J, Nordenstrom J, Perbeck L. Reoperation for suspected primary hyperparathyroidism. Br J Surg 1993;80:453-6.
13	Berczi C, Mezosi E, Galuska L, Varga J, Bajnok L, Lukacs G, et al. Technetium-99m-sestamibi/pertechnetate subtraction scintigraphy vs. ultrasonography for preoperative localization in primary hyperparathyroidism. Eur Radiol 2002;12:605-9.
14	Billotey C, Sarfati E, Aurengo A, Duet M, Mündler O, Toubert ME, et al. Advantages of SPECT in technetium-99m-sestamibi parathyroid scintigraphy. J Nucl Med 1996;37:1773-8.
15	Patel CN, Salahudeen HM, Lansdown M, Scarsbrook AF. Clinical utility of ultrasound and 99mTc sestamibi SPECT/CT for preoperative localization of parathyroid adenoma in patients with primary hyperparathyroidism. Clin Radiol 2010;65:278-87.