Abnormal Parathyroid Research Articles

Association of Histological Findings with Tc-99m Sestamibi Parathyroid Imaging in Hyperfunctional Parathyroid Gland

Background: Hyperthyroidism is a relatively common disorder that results from increased production of parathormone. Tc-99m sestamibi (MIBI) scanning is used for localization of abnormal parathyroid gland, with high reported sensitivities. However, there exists a group of patients in whom MIBI scan is either equivocal or negative. Objectives: The aim of this study was to see association of the histological features of pathologic parathyroid gland with MIBI scan in hyperfunctional parathyroid gland. Methodology: This retrospective study was conducted with primary hyperthyroidism who underwent MIBI scan. The data were collected from the record from January 2012 to December 2014 for a period of two years. All patients underwent parathyroid surgery followed by histopathological examination. According to oxyphil cell distribution patients are divided in three groups. Group I comprised of >25.0% oxyphil cell; group II included the 25 to 75% oxyphil cell and group III included >75% of oxyphil cell. Result: A total 56 patients with hypercalcaemia and high serum parathyroid hormone (PTH) level were studied. Mean age was 41.3(±19.8) years with a range of 21 to 63 years. MIBI scan was true positive in 34(60.7%) cases and false negative in 22(39.3%) cases. In group I MIBI scan was true positive in 4(36.3%) cases and false negative in 7(63.7%) cases. In group II MIBI scan showed positive in 17(62.9%) cases and negative in 10(37.1%) cases. In group III out of 18 patients 13(72.2%) showed MIBI scan positive whereas, 5(27.8%) showed negative scan. The sensitivity was 36.3% in group I whereas, 62.9% and 72.2% in group II and group III respectively. Conclusion: Based on these findings, it could be say that Tc–99m setamibi uptake correlate with parathyroid oxyphil cell content, and false negative scan can occur with parathyroid glands containing predominantly clear cell.Journal of National Institute of Neurosciences Bangladesh, 2016;2(1):14-18

Factors Associated With Discordance Between Preoperative Parathyroid 4-Dimensional Computed Tomographic Scans and Intraoperative Findings During Parathyroidectomy

Parathyroid 4-dimensional computed tomographic scans (4D-CTs) have emerged as an accurate and cost-effective initial localization study for patients with primary hyperparathyroidism. However, potential limitations and factors affecting the accuracy of preoperative 4D-CTs remain poorly defined. To characterize factors associated with missed parathyroid lesions on preoperative 4D-CTs and to investigate patterns of commonly observed errors. A prospectively accrued patient database was analyzed from September 1, 2011, through October 31, 2016. The study was performed in a tertiary referral center. Consecutive patients with primary hyperparathyroidism undergoing preoperative 4D-CTs and subsequent parathyroidectomy were included in the study. Discordance between preoperative 4D-CTs and intraoperative findings in the number and location of abnormal parathyroid lesions. Of 411 patients studied (mean [SD] age, 59 [14] years; 325 [79.1%] female), 123 (29.9%) had discordance between preoperative 4D-CTs and intraoperative findings. Among the 411 patients, 75 (18.2%) had major discordance, including incorrectly localized adenoma on the contralateral side of the neck, missed double adenoma, and absence of any abnormal lesion detected on 4D-CTs. Compared with concordant cases, discordant cases had higher frequencies of multigland disease (66.7% [82 of 123] vs 24.3% [70 of 288], P < .001) and multinodular goiter or thyroid nodule (40.7% [50 of 123] vs 29.2% [84 of 288], P = .02). Missed parathyroid lesions were smaller (mean [SD], 0.86 [0.29] vs 1.24 [0.50] cm; P < .001) and were more likely to be in the inferior position (65.4% [87 of 133] vs 38.1% [177 of 465], P < .001). Parathyroid lesion size of 10 mm or less (odds ratio [OR], 4.37; 95% CI, 2.24-8.54), multigland disease (OR, 7.63; 95% CI, 3.49-16.69), multinodular goiter or thyroid nodule (OR, 1.82; 95% CI, 1.01-3.28), and parathyroid lesion in the inferior position (OR, 6.82; 95% CI, 3.10-14.99) were independently associated with discordant 4D-CT results. Multigland disease was most strongly associated with discordance between preoperative 4D-CTs and intraoperative findings, followed by parathyroid lesion in the inferior position and parathyroid lesion size of 10 mm or less. Awareness of these potential pitfalls may allow surgeons to better leverage this new localization technique in preoperative planning and intraoperative troubleshooting.

Sensitivity of 3-Dimensional Sonography in Preoperative Evaluation of Parathyroid Glands in Patients With Primary Hyperparathyroidism.

Preoperative localization of parathyroid adenomas in patients with primary hyperparathyroidism facilitates targeted surgery. We assessed the sensitivity of 3-dimensional (3D) sonography for preoperative localization of abnormal parathyroid glands. We conducted a retrospective review of patients who underwent parathyroidectomy for primary hyperparathyroidism at a single site at our institution. We compared preoperative 2-dimensional (2D) sonography, 3D sonography, and sestamibi scans with final gland localization at surgery. Two readers reviewed the sonograms to assess inter-reader variability. From January 2010 through April 2015, 52 patients underwent parathyroidectomy after preoperative 2D sonography, 3D sonography, and sestamibi scans. Three-dimensional sonography had sensitivity of 88-92% compared with 69-71% for 2D sonography for gland localization. In patients in whom sonography and sestamibi scans localized abnormalities to the same side, the sensitivities were 100% (43 of 43) for 3D sonography and 96% (48 of 50) for 2D sonography. Three-dimensional sonography had significantly higher sensitivity for localization of glands smaller than 500 mg compared with 2D sonography (88% versus 58%; P = .012). There was better inter-reader agreement between the radiologists when using 3D sonography (κ = 0.65) compared with 2D sonography (κ = 0.41). We found a significantly higher sensitivity and better inter-reader agreement for 3D sonography compared with 2D sonography for preoperative identification of abnormal parathyroid glands, especially among smaller glands.

Influence of single photon emission computed tomography (SPECT) reconstruction algorithm on diagnostic accuracy of parathyroid scintigraphy: Comparison of iterative reconstruction with filtered backprojection.

Background & objectives:Preoperative localization of parathyroid lesions is essential for improving the results in patients with primary hyperparathyroidism. The purpose of this study was to evaluate retrospectively the value of technetium-99m (Tc-99m) methoxyisobutylisonitrile (MIBI) single photon emission computed tomography (SPECT) and to compare the diagnostic accuracy of iterative reconstruction (IR) and filtered backprojection (FBP) reconstruction algorithms about localization of parathyroid lesions.Methods:Forty four patients with primary hyperparathyroidism, in whom histopathological correlation could be performed, were included in the study. Dual-phase Tc-99m parathyroid scintigraphy was performed 20 and 120 min after injection of 740 MBq Tc-99m MIBI in all patients. Tomographic images were acquired 120 min after the administration of radiopharmaceutical. The SPECT data were evaluated using an IR as well as a FBP algorithm. In 23 of 44 patients, SPECT acquisitions were performed in 64×64 matrix; in the remaining 21 patients, tomographic data were collected in 128×128 matrix. The imaging results were compared with pathological findings and sensitivities of both reconstruction algorithms, and planar views were calculated.Results:Using planar MIBI scans, abnormal parathyroid glands were correctly localized in 75 per cent of the cases. Sensitivity increased to 77 per cent using SPECT with FBP and to 84 per cent with IR. When the sensitivities were calculated according to the acquisition matrix, these were 95 per cent (20/21) and 85 per cent (18/21) for IR and FBP, respectively in patients in whom 128×128 matrix was used. The sensitivities were lower in patients who were imaged with 64×64 matrix; these were calculated as 74 per cent (17/23) and 70 per cent (16/23) with IR and FBP, respectively.Interpretation & conclusions:Our findings showed that compared to planar scintigraphy, Tc-99m MIBI SPECT was more sensitive diagnostic modality in the detection of abnormal parathyroid tissues. Image quality and sensitivity may be improved further when larger matrices with IR are used instead of FBP algorithm.

Feasibility and safety of minimally invasive radioguided parathyroidectomy using very low intraoperative dose of Tc-99m MIBI

BackgroundSurgical resection of the abnormal parathyroid glands is the only curative treatment for primary hyperparathyroidism (PHPT). Radioguided parathyroidectomy with technetium-99m (TC-99m) sestamibi has been successfully used in patients with PHPT.This study was designed to evaluate the results of a series of patients with PHPT who underwent minimally invasive radioguided parathyroidectomy (MIRP) using very low dose (1 mCi) of TC-99m sestamibi (MIBI) without application of intraoperative parathyroid hormone (PTH) assay or frozen section analysis. MethodsEighty-seven patients with PHPT were prospectively studied from November 2012 to January 2015. Following neck ultrasound (US) and MIBI scan concordant for single gland disease, patients underwent MIRP using a handheld gamma probe. The technique involved injecting of 1 mCi MIBI in the operative room before the beginning of the intervention. All patients were followed up for a minimum of 6 months postoperatively. ResultsMIRP was successfully performed in 86 out of 87 patients (98.85%). The Gamma probe was particularly useful in detection of ectopic parathyroid adenomas in upper mediastinum. Mean operative time was 23.95 ± 7.982 min and mean hospital stay was 1.44 ± 0.604 days. No major surgical complications were recorded. ConclusionsThe MIRP technique using very low dose (1 mCi) of Tc-99m MIBI without intraoperative PTH assay and frozen section analysis resulted in excellent cure rate for PHPT. This technique involves a radiation exposure to patients and surgical staffs 20 times lower than conventional MIRP using 20 mCi Tc-99m MIBI. Besides, patients with PHPT due to ectopic parathyroid adenoma may especially benefit from MIRP.

18F Fluorocholine PET/MR Imaging in Patients with Primary Hyperparathyroidism and Inconclusive Conventional Imaging: A Prospective Pilot Study.

Purpose To investigate the performance of flourine 18 (18F) fluorocholine (FCH) positron emission tomography (PET)/magnetic resonance (MR) imaging in patients with hyperparathyroidism and nonlocalized disease who have negative or inconclusive results at ultrasonography (US) and technetium 99m (99mTc) sestamibi scintigraphy. Materials and Methods This study was approved by the institutional review board. Between May and December 2015, 10 patients (mean age, 70.4 years; range, 58-82 years) with biochemical primary hyperparathyroidism and inconclusive results at US and 99mTc sestamibi scintigraphy were prospectively enrolled. All patients gave informed consent. Directly after administration of 3 MBq/kg of FCH, PET imaging was performed, followed by T1- and T2-weighted MR imaging before and after gadolinium enhancement. Intraoperative localization and histologic results were the reference standard for calculating sensitivity and positive predictive value. The Wilcoxon rank test was used to calculate the mean difference in maximum standardized uptake value (SUVmax) between abnormal parathyroid uptake and physiologic thyroid uptake. The Wilcoxon rank-sum test was performed. Results MR imaging alone showed true-positive lesions in five patients and a false-positive lesion in one patient. FCH PET/MR imaging allowed correct localization of nine of 10 adenomas (90% sensitivity), without any false-positive results (100% positive predictive value). One patient had four-gland hyperplasia, of which three hyperplastic glands were not localized. The median SUVmax of the nine preoperatively identified adenomas was 4.9 (interquartile range, 2.45-7.35), which was significantly higher than the SUV, 2.7 (interquartile range, 1.6-3.8), of the thyroid (P = .008). Conclusion FCH PET/MR imaging allowed localization of adenomas with high accuracy when conventional imaging results were inconclusive and provided detailed anatomic information. More patients must be examined to confirm our initial results, and the accuracy of FCH PET/MR imaging for localization of glands in patients with four-gland hyperplasia remains to be investigated. © RSNA, 2017.

Regional Clinical and Biochemical Differences among Patients with Primary Hyperparathyroidism.

Background:Environmental habitat may play a role in clinical disparities of primary hyperparathyroidism (pHPT) patients.Aims:To compare preoperative clinical symptoms and associated conditions and surgical findings in patients with pHPT, living in different geographical regions from the Black Sea, Mediterranean and Anatolia regions.Study Design:Retrospective, clinical-based multi-centric study of 694 patients with pHPT.Methods:Patients from 23 centers and 8 different geographical regions were included. Data related to baseline demographics, clinical, pathologic and treatment characteristics of 8 regions were collected and included age, gender, residential data, symptoms, history of fracture, existence of brown tumor, serum total Ca and p levels, serum parathormone (PTH) levels, serum 25-OH vitamin D levels, bone mineral density, size of the resected abnormal parathyroid gland(s), histology, as well as the presence of ectopia, presence of dual adenoma, and multiple endocrine neoplasia (MEN)- or familial-related disease.Results:The median age was 54. Asymptomatic patient rate was 25%. The median PTH level was 232 pg/mL and serum total Ca was 11.4 mg/dL. Eighty-seven percent of patients had an adenoma and 90% of these had a single adenoma. Hyperplasia was detected in 79 patients and cancer in 9 patients. The median adenoma size was 16 mm. Significant parameters differing between regions were preoperative symptoms, serum Ca and p levels, and adenoma size. All patients from South-East Anatolia were symptomatic, while the lowest p values were reported from East Anatolia and the largest adenoma size, as well as highest Ca levels, were from Bulgaria.Conclusion:Habitat conditions vary between geographical regions. This affects the clinicopathological features of patients with pHPT.

Parathyroid Embryology, Anatomy, and Pathophysiology of Primary Hyperparathyroidism

Unregulated overproduction of parathyroid hormone (PTH) from an abnormal parathyroid gland is the origin of primary hyperparathyroidism (PHPT). Patients who have an elevated serum calcium concentration have a problem in one or more of their parathyroid glands. To understand this disease state adequately and provide appropriate treatment, a thorough understanding of parathyroid embryology, anatomy, physiology, and pathophysiology is essential. In this manuscript, we review our current understanding of parathyroid gland embryology, anatomy, histology, physiology, and pathophysiology.

Accuracy of Combined Ultrasonography and Tc99m Sestamibi Scintigraphy in Preoperative Localization of Primary Hyperparathyroidism

Background: Primary hyperparathyroidism remains one of the leading causes of hypercalcemia in the world today. To plan the appropriate surgery with the least morbidity for the patient, preoperative localization of the abnormal parathyroid gland is necessary. Tc99m sestamibi scintigraphy and ultrasonography are the two main modalities for imaging the parathyroid glands. Patients and methods: This prospective interventional non-randomized non-controlled study was conducted in the Department of General Surgery at Ain Shams University hospitals in the period from April 2013 to October 2016 on thirty patients (7 males and 23 females) with primary hyperparathyroidism. Informed consent was obtained from all patients included in the study. Results: Out of thirty patients, the combined preoperative ultrasonography and Tc99m sestamibi scintigraphy was accurate in twenty eight patients (93.33%) while they could not identify the pathological gland in two patients (6.66%). Accuracy of ultrasonography alone was 76.66% (23 patients), while accuracy of T99m sestamibi scan alone was 86.66% (26 patients). Conclusion: The preoperative combination of ultrasonography and Tc99m sestamibi scintigraphy is effective with high accuracy in predicting the location of abnormal parathyroid gland(s) in patients with primary hyperparathyroidism.

Vitamin D status and its associations with rheumatoid arthritis in Korean women: the Korean National Health and Nutrition Examination Survey 2008-2014.

In the present study, vitamin D status and its associations with rheumatoid arthritis in Korean women were investigated. Total 2,162 women’s data from the Korea National Health and Nutrition Examination Survey during 2008–2014 ware analyzed by complex sampling design logistic regression analysis and complex sampling design general linear model. Women who over 19 years old were included, and who has osteoporosis or abnormal parathyroid hormone or renal failure or liver cirrhosis or abnormal creatinine were excluded. Age and body mass index were used as covariate. In the present study, we have shown that vitamin D status were not associated with development of rheumatoid arthritis in Korean women as well were not associated with pain and quality of life in Korean women with rheumatoid arthritis. Based on the present study and considering the effects of vitamin D on fracture and osteoporosis, it can be suggested that additional cohort study and cost-effectiveness analysis are needed.

ANALYSIS OF FACTORS AFFECTING OUTCOME OF ULTRASOUND-GUIDED RADIOFREQUENCY HEAT ABLATION FOR TREATMENT OF PRIMARY HYPERPARATHYROIDISM IN DOGS.

Radiofrequency (RF) parathyroid ablation is a noninvasive treatment for hyperparathyroidism in dogs. There are no published data assessing factors associated with RF parathyroid ablation success or failure in order to guide patient selection and improve outcome. The purpose of this retrospective analytical study was to determine whether imaging findings, biochemical data, or concurrent diseases were associated with RF heat ablation treatment failure. For inclusion in the study, dogs must have had a clinical diagnosis of primary hyperparathyroidism, undergone cervical ultrasound and RF ablation of abnormal parathyroid tissue, and must have had at least 3 months of follow-up information available following the date of ultrasound-guided parathyroid ablation. Dogs were grouped based on those with recurrent or persistent hypercalcemia and those without recurrent or persistent hypercalcemia following therapy. Parathyroid nodule size, thyroid lobe size, nodule location, and presence of concurrent disease were recorded. Recurrence of hypercalcemia occurred in 9/32 dogs that had ablation of abnormal parathyroid tissue (28%) and one patient had persistent hypercalcemia (3%) following parathyroid ablation. Nodule width (P = 0.036), height (P = 0.028), and largest cross-sectional area (P = 0.023) were larger in dogs that had recurrent or persistent hypercalcemia following ablation. Hypothyroidism was more common in dogs with recurrent disease (P = 0.044). Radiofrequency ablation was successful in 22/32 (69%) dogs. Larger parathyroid nodule size and/or concurrent hypothyroidism were associated with treatment failure in dogs that underwent ultrasound-guided RF parathyroid nodule ablation.

Is intraoperative parathyroid hormone monitoring necessary for primary hyperparathyroidism with concordant preoperative imaging?

BackgroundThe purpose of this study was to determine if intraoperative parathyroid hormone (PTH) monitoring is necessary in patients with concordant ultrasound and sestamibi imaging. MethodsClinical factors, intraoperative findings and outcome were correlated with imaging results in patients with primary hyperparathyroidism who underwent parathyroidectomy with concordant ultrasound and sestamibi imaging. ResultsThere were 127 patients with primary hyperparathyroidism and concordant imaging who underwent parathyroidectomy. Seven patients (5.5%) had intraoperative findings that were discordant with imaging: 2 (1.6%) had an adenoma at a different location, 2 (1.6%) had double adenomas and 3 (2.4%) had asymmetric hyperplasia. Gland weight and preoperative PTH levels were greater for patients with concordant operative and imaging findings (p < 0.05). ConclusionSix percent of patients with concordant ultrasound and sestamibi imaging had unexpected intraoperative findings. Intraoperative PTH monitoring remains a necessary adjunct even with concordant imaging to ensure identification of abnormal parathyroid glands and cure of hyperparathyroidism.

AIUM Practice Parameter for the Performance of a Thyroid and Parathyroid Ultrasound Examination.

AIUM Practice Parameter for the Performance of a Thyroid and Parathyroid Ultrasound Examination.

Intraoperative ex vivo parathyroid aspiration: A point-of-care test to confirm parathyroid tissue

Exvivo aspiration of a parathyroid gland with intraoperative parathyroid hormone determination is a method for intraoperative confirmation of parathyroid tissue. The aim of this study was to describe the use and applicability of this technique at a single, high-volume institution. This is a retrospective review of patients who underwent parathyroidectomy and exvivo aspiration of suspected, abnormal parathyroid tissue for intraoperative parathyroid hormone level (pg/mL). Sensitivity and specificity were calculated for aspirate intraoperative parathyroid hormone levels which were compared with the baseline serum aspirate intraoperative parathyroid hormone obtained prior to parathyroid excision in each patient. Of 921 tissue aspirates, 847 (92%) were confirmed as parathyroid on histopathology, with a mean±standard deviation aspirate intraoperative parathyroid hormone of 3,838±1,615 pg/mL. The 847 aspirates included 833 (98%) with aspirate intraoperative parathyroid hormone levels greater than the serum aspirate intraoperative parathyroid hormone and 14 (2%) with aspirate intraoperative parathyroid hormone levels less than the serum aspirate intraoperative parathyroid hormone; 74 (8%) aspirates were not parathyroid tissue, with a mean aspirate intraoperative parathyroid hormone level of 25±12.7 pg/mL. An aspirate intraoperative parathyroid hormone ≥1.5 times the serum aspirate intraoperative parathyroid hormone represented the optimal threshold for confirmation of parathyroid tissue. Intraoperative exvivo aspiration of presumed parathyroid gland is a sensitive and specific point-of-care method to confirm the presence of parathyroid tissue. An aspirate intraoperative parathyroid hormone ≥1.5 times greater than the baseline serum aspirate intraoperative parathyroid hormone minimizes the likelihood of misidentifying parathyroid tissue.

Location of abnormal parathyroid glands: lessons from 810 parathyroidectomies

BackgroundPrimary hyperparathyroidism (pHPT) is commonly treated with targeted parathyroidectomy (PTX) guided by preoperative imaging and intraoperative parathormone monitoring. Despite advanced imaging techniques, failure of parathyroid localization still occurs. This study determines the anatomical distribution of single abnormal parathyroid glands, which may help direct the surgeon in PTX when preoperative localization is unsuccessful. MethodsA retrospective review of prospectively collected data of 810 patients with pHPT who underwent initial PTX at a tertiary medical center was performed. All patients had biochemically confirmed pHPT and single-gland disease. Abnormal parathyroid gland localization was determined at time of operation, correlated with operative and pathology reports, and confirmed by operative success defined as eucalcemia for ≥6 mo after PTX. Patients with multiple endocrine neoplasia, secondary, tertiary, or familial hyperparathyroidism, multiglandular disease, parathyroid cancer, and ectopic glands were excluded. Data were analyzed by chi-square and Z-test analyses. ResultsAmong 810 patients who underwent PTX for pHPT, single abnormal parathyroid glands were unequally distributed among the four eutopic locations (left superior, 15.7%; left inferior, 31.3%; right superior, 15.8%; right inferior, 37.2%; P < 0.01). Abnormal inferior parathyroid glands (68.5%) were significantly more common than abnormal superior glands (31.5%), respectively (P < 0.01). In men, the most common location for single abnormal parathyroid glands was the right inferior position (43.4%, P < 0.01). Overall, there was no significant difference in laterality. ConclusionsThis large series of patients suggests that single eutopic abnormal parathyroid glands are more likely to be inferior. In men, moreover, if an abnormal parathyroid gland is not localized preoperatively, the right inferior location should be explored first. Nevertheless, successful PTX remains predicated on knowledge of parathyroid anatomy, experience, and judgment of the surgeon.

Identifying Parathyroid Hormone Disorders and their Phenotypes through a Bone Health Screening Panel: It's not Simple Vitamin D Deficiency!

To determine the utility of bone health screening panels in identifying disorders of parathyroid gland secretions. A retrospective analysis of biochemical parameters in a bone health screening panel (BHSP) was conducted. Low and high cutoffs were applied to determine hypofunctioning and hyperfunctioning conditions related to parathyroid hormone. Clinical phenotypes of parathyroid gland abnormalities were determined using a combination of levels of calcium, 25-hydroxyvitamin D, and intact parathyroid hormone (iPTH). A PTH nomogram was applied to calculate the maximum expected PTH for existing levels of 25-hydroxyvitamin D. Medical records of patients were reviewed for clinical validation of biochemical findings. Sixty-eight percent of subjects showed abnormal PTH secretion. Primary hyper- and hypoparathyroidism were detected in 1% (n = 5) and 0.4% (n = 2) of subjects, respectively. Normocalcemic hyperparathyroidism and hypercalcemia with inappropriately high-normal PTH were identified in 8.5% (n = 37) and 2% (n = 10) of subjects, respectively. All subjects with primary and normocalcemic hyperparathyroidism had higher measured PTH than calculated maximum PTH using the PTH nomogram. Secondary hyperparathyroidism and functional hypoparathyroidism were present in 18% (n = 88) and 39% (n = 194) of subjects, respectively. High prevalence of bone pains, renal stones, and low bone mineral density were identified in patients with abnormal PTH secretion. Panel testing is useful in early diagnosis of metabolic bone disorders related to PTH. A BHSP helps identify normocalcemic hyperparathyroidism and hypercalcemia with inappropriately high PTH. 25OHD = 25-hydroxyvitamin D AKUH = Aga Khan University Hospital BHSP = bone health screening panel iPTH = intact parathyroid hormone maxPTH = maximum parathyroid hormone MBD = metabolic bone disease NCHPT = normocalcemic hyperparathyroidism PHPT = primary hyperparathyroidism PTH = parathyroid hormone SHPT = secondary hyperparathyroidism VDD = vitamin D deficiency.

Sestamibi Positive Vs Negative Scan In Primary Hyperparathyroidism; A Clinical Dilemma

Objectives: In primary hyperthyroidism Tc-99m Sestamibi (MIBI) scanning is commonly used for localization of abnormal parathyroid gland and the reported sensitivity is very high. However, false negative scan remain a problem. We examined whether serum calcium and parathormone (PTH) level have any impact in the sensitivity of MIBI scan.Study design: A retrospective review of 55 patients with primary hyperparathyroidism who underwent MIBI scan from January 2012 to December 2014 were included in this study. All patients underwent parathyroid surgery followed by histopathological confirmation.Results: In total, 55 patients were studied. Mean age was 41.3 ± 19.8 years (range 21-63 years). MIBI scan was true positive in 37 cases and false negative in 18 cases. The sensitivity of MIBI scan was 67.2 %. Mean serum calcium level was 12.3 mg/ dL. More than 62.2 % of patients with calcium level greater than 12.3 mg/dL had a positive scan as compared with 37.8% of those with lesser value (P&lt;0.05). Similarly a serum PTH level greater than 316 ± 139 pg/mL correlated with positive scans in 78.4 % as opposed to 21.6 % in those with lower levels (P&lt; 0 .01).Conclusion: Lower calcium and PTH level significantly correlate with reduced sensitivity of MIBI scan. Although we did not find the best cut-off level of serum calcium and PTH level that can predict a positive scan.Bangladesh J. Nuclear Med. 17(2): 142-145, July 2014

Video-assisted mediastinoscopic removal of ectopic parathyroid adenoma combined with standard cervical exploration

Background Primary hyperparathyroidism (HPT) is one of the most common endocrine disorders. The standard treatment is surgical removal via a cervical incision. In rare cases, abnormal parathyroid tissue may be present in the mediastinum and therefore inaccessible through the standard incision.

Impact of preoperative imaging on surgical approach for primary hyperparathyroidism: Data from single institution in India.

Context:Preoperative localization of parathyroid adenoma is essential in deciding the surgical approach of parathyroidectomy.Aim:To describe clinical and biochemical profile, evaluate preoperative imaging modalities and surgical approach in patients with primary hyperparathyroidism (PHPT).Methodology:This was a retrospective study conducted at the single institution. All patients who underwent evaluation and surgery for PHPT from 2011 to 2015 were included in the study.Results:A total of 100 patients underwent surgery for PHPT. Mean (standard deviation) age was 51.6 (15.9) years with female to male ratio of 1.7:1. Forty patients had severe symptoms, and sixty had mild to moderate symptoms. The sensitivity of technetium-99m hexakis (2-methoxyisobutylisonitrile) (MIBI) scan and ultrasonography (USG) neck in identifying abnormal parathyroid gland was 93% (93/100) and 98% (98/100), respectively. The MIBI scan results of 90/93 (96.7%) patients corresponded with their surgical findings whereas preoperative USG findings of 96/98 patients (98%) showed correlation with operative findings. Intraoperative intact parathyroid hormone (IOPTH) levels at 10 min postexcision were measured in forty patients (minimally invasive parathyroidectomy = 38, bilateral neck exploration = 1, and unilateral neck exploration = 1). All patients except two had <50% fall in IOPTH. Adenoma weight was positively correlated with preoperative intact PTH.Conclusion:We found that USG has higher sensitivity (98%) than MIBI scan (93%) in localizing abnormal parathyroid gland. Moreover, USG had a higher preoperative localization accuracy (93%) than MIBI scan (90%), allowing to choose an appropriate surgical approach. A higher proportion of patients (60%) had mild/asymptomatic form of PHPT.

Computed Tomography and Magnetic Resonance Imaging of the Thyroid and Parathyroid Glands.

Computed tomography (CT) and magnetic resonance imaging (MRI) are advanced imaging modalities that are not typically utilized as part of the initial evaluation of thyroid and parathyroid pathology. However, both modalities have applications in complex cases, particularly in the reoperative setting and in operative planning for initial or recurrent carcinomas. As part of a multimodal approach, CT and MRI can increase the successful preoperative localization of abnormal parathyroid glands. Newer imaging modalities, such as PET-CT and SPECT-CT in thyroid imaging, and 4D-CT in parathyroid imaging, can provide information on the anatomy as well as the function of pathologic tissues. Both modalities provide excellent assessment of the extent of disease, local invasion and distant metastases. Drawbacks include cost and availability, and these should be weighed against benefits in the context of the management of thyroid and parathyroid disease.