Four-gland Exploration Research Articles

8651 Parathyroiditis- An Unusual Autoimmune Mediated-Process Presenting as Primary Hyperparathyroidism

Abstract Disclosure: M. Abdel-Malek: None. K. Alexiadou: None. N. Chander: None. S. Damji: None. S. Mukhopadhyay: None. F. Palazzo: None. T. Tan: None. Background: Inflammatory processes of the parathyroid gland are rare, not widely reported in the literature nor fully understood.Clinical case: A 67-year-old female was referred to the Endocrine team with a diagnosis of primary hyperparathyroidism in the context of severe symptoms related to hypercalcaemia and a background of osteoporosis. There was no known family history of endocrinopathies or autoimmune disease. Despite Cinacalcet treatment, she had a significant hypercalcaemia with an adjusted Calcium level of 2.99 mmol/L (RR 2.20 to 2.60) and a high Parathyroid Hormone (PTH) level of up to 46.1 pmol/L (RR 1.6 to 7.2). Localisation studies in the form of a Sestamibi and ultrasound scan failed to locate a parathyroid adenoma.During a four-gland exploration procedure, she had two pathological glands in the right inferior and left superior positions. She therefore underwent a bilateral inferior parathyroidectomy with no intra or immediate post-operative complications. On removal of the two abnormal parathyroid glands, her PTH level dropped from its peak of 48.1pmol/L to 12.2 pmol/L. However, most remarkably, the outcome of her histology revealed morphological appearances of a chronic parathyroiditis.On post-surgery follow-up, her symptomology of fatigue, nausea, abdominal pain and bowel symptoms resolved in addition to reported improvement in energy level. Her adjusted Calcium remained in the range 1.88mmol/L to 2.32mmol/L with a normalised and appropriately reactive PTH level.Over a year later, she developed sudden onset alopecia as well as oncholysis. Her autoimmune serology was negative with no other endocrine biochemical disturbance observed suggestive of an autoimmune-mediated polyendocrine process.She later developed hypocalcaemia despite high-dose Adcal D3, replete Vitamin D status and detectable PTH level (3.7 to 5.0 pmol/L), requiring admission for intravenous Calcium infusion. She was diagnosed with a functional hypoparathyroidism and subsequently commenced on regular Alfacalcidol with good symptomatic response. Conclusion: This case illustrates how a chronic parathyroiditis can mimic a primary hyperparathyroidism, and the even more unusual late presentation of a functional hypoparathyroidism in this context. Presentation: 6/2/2024

Utility of 99mTc-Sestamibi Single-Photon Emission Computed Tomography (SPECT)/CT Single Imaging Strategy in the Preoperative Localization of Parathyroid Adenoma.

Background Primary hyperparathyroidism is an endocrinopathy associated with dysregulated calcium homeostasis. The most common etiology is a parathyroid adenoma most definitely managed via a parathyroidectomy. The two main surgical approaches include a minimally invasive parathyroidectomy (MIP) and open four-gland exploration (4-GE). MIP is the preferred operative strategy since it is associated with less postoperative complications. Accurate preoperative imaging is essential in informing the optimal approach to surgery. MIP is only considered if adenoma is able to be localized precisely. The most commonly used imaging modality includes ultrasound and sestamibi single-photon emission computed tomography (SPECT)/CT, either as a singleor combination strategy. Other options include MRI, PET, and 4D CT. There is no universally accepted preoperative imaging strategy. The literature is discordant and recommendations proposed by existing guidelines are incongruous. Objectives This study aimed to evaluate currently utilized preoperative parathyroid imaging modalities at our institution and correlate them with surgical and histological findings to determine the most efficient imaging strategy to detect adenomas for our patient cohort. This will ultimately guide the best surgical approach for patients receiving parathyroidectomies. Methods This is a retrospective observational study of all patients undergoing first-time surgery for biochemically proven primary hyperparathyroidism at our institution over the past five years. Multiple data points were collected including modality of preoperative disease localization, operation type, final histopathology, biochemical investigations, and cure rate. Patients were categorized into one of three groups based on the method of disease localization. Results A total of 244 patients had parathyroidectomies performed at our institution in the past five years from January 2018 to December 2022. Ninety-six percent (n=235) of all patients received dual imaging preoperatively with SPECT/CT and ultrasound performed on the same day and therefore included in this study. A total of 64.3% (n=151) underwent MIP. Eighty percent (n=188) of all histopathology revealed adenomas and 26.8% (n=63) of patients had adenoma localized on SPECT/CT only (sensitivity: 58.1%, specificity: 71%, and positive predictive value {PPV}: 85.7%). A total of 9.8% (n=23) had adenoma localized on ultrasound only (sensitivity: 15.6%, specificity: 73.3%, and PPV: 65.2%). A total of 45.1% (n=106) were dual localized on both SPECT/CT and ultrasound (sensitivity: 75.6%, specificity: 46.6%, and PPV: 84.9%). The cure rate was 91.5% in the dual-localized group, 86% in the dual-unlocalized group, and 96.5% when localized with SPECT/CT alone. Conclusion A dual-imaging modality with SPECT/CT and ultrasound should remain the first-line imaging strategy. This approach has higher sensitivity rates and poses no inherent patient or surgical-related risks. Patients with disease unlocalized on SPECT/CT alone had a positive predictive value, specificity, and likelihood ratio for adenoma detection comparable to dual-localized patients. Therefore, SPECT/CT alone is sufficient for directing MIP in the presence of a negative ultrasound.

Determination of Lesion Localization with Intraoperative Gamma Probe in the Presence of a Primary Parathyroid Lesion with Early Wash-Out in Radionuclide

Objective: In this research, we aimed to evaluate the success of the minimally invasive surgical method performed with intraoperative gamma-probe despite early wash-out in solitary primary parathyroid lesions and to contribute to the literature on this subject. Methods: This retrospective study included 48 adult patients diagnosed with hyperparathyroidism, with an average parathormone value of 105 pg/mL (range: 82-127 pg/mL). Radionuclide imaging was conducted using Tc-99m sestamibi and Tc-99m-pertechnetate. Minimally invasive surgery with an intraoperative gamma probe was planned for patients with primary parathyroid lesions and surgical indications. At the conclusion of the operation, count equalization was observed in all four quadrants. Results: Minimally invasive surgery was performed on 42 patients with the assistance of an intraoperative gamma probe. In 6 patients, the procedure was extended to conduct a four-gland exploration due to early wash-out. Each patient had one pathological lesion removed, all of which were histopathologically confirmed as parathyroid adenomas. Among the 6 patients with extended surgeries, 4 experienced early wash-out, and all 6 had been diagnosed with multinodular goiter. Conclusion: In cases with primary hyperparathyroidism, it is aimed to remove the pathological lesion with minimally invasive surgery and leave the glands that continue their normal function in place. Preoperative localization methods help the surgeon in this regard, but pathologies in the surrounding tissue can reduce the success of minimally invasive surgery.

PSAT202 A Rare Case of Four-Gland Parathyroid Adenomas

Abstract Background Amongst patients diagnosed with primary hyperparathyroidism, 80% have been identified to have a single parathyroid gland involvement, with 10% involving two glands or more. Case A 71-year-old female with medical history of hypothyroidism, multinodular goiter, CKD stage 3a, recurrent nephrolithiasis and hyperparathyroidism presented for evaluation of hypercalcemia. She was diagnosed with hyperparathyroidism 9 years prior to presentation however she preferred medical management with cinacalcet. For the past 5 months, she had been experiencing worsening fatigue, constipation, body aches and appetite loss. Further blood analysis revealed PTH 1176 pg/mL (14-64 pg/mL), TSH 2.69 uU/mL (0.35-4.94 uU/mL), free T4 1.12 ng/dL (0.60-1.89 ng/dL), vitamin D, 25-Hydroxy 24 ng/mL (30-80 ng/mL), serum calcium 12.6 mg/dl (8.9-10.4 mg/dL), ionized calcium 1.65 mmol/L (1.14-1.33 mmol/L), phosphorus 1.9 mg/dl (2.4-4.8 mg/dl), magnesium 1.0 mg/dl (1.8-3.0 mg/dL). Thyroid ultrasound revealed a left isthmus heterogenous solid nodule measuring up to 2.0 cm and a separate nodule superior to the isthmus measuring up to 0.6 cm. Subsequent NM parathyroid scan was limited due to diffuse uptake of enlarged nodular thyroid. Although limited, imaging did reveal a small focus of uptake lateral to the right lower pole concerning for parathyroid adenoma. A CT 4D neck with and without contrast demonstrated a suspicious parathyroid adenoma posterior to the inferior aspect of the left thyroid measuring up to 1.7 cm, an additional 0.8 cm questionable node, and a 4 cm multicystic mass inferior to the right thyroid lobe concerning for exophytic thyroid nodule or multi cystic parathyroid adenoma. Due to persistence of symptoms and significantly elevated PTH levels concerning for carcinoma, decision was made to undergo a four-gland parathyroid exploration and a right hemithyroidectomy. A right superior parathyroid adenoma was identified; after resection, intraoperative PTH levels failed to improve which prompted further exploration. Left superior and inferior parathyroid adenomas were identified and resected. An ectopic nodule located in the right superior mediastinum with surrounding normal parathyroid tissue was identified and dissected, leaving parathyroid tissue behind. Post operatively, PTH levels appropriately decreased to 54 pg/ml. Pathology of identified parathyroid glands had hypercellular parathyroid tissue with fibrous capsule, consistent with adenomas. Interestingly, the pathology of the presumed ectopic nodule was consistent with atypical parathyroid adenoma. Immunostatins with parafibromin demonstrated nuclear immunoreactivity in the lesional cells, consistent with a benign neoplasm. Patient developed symptomatic hypocalcemia following surgery. She was gradually weaned off calcitriol and is currently normocalcemic. Conclusion It is extremely rare to have adenoma of 4 parathyroid glands simultaneously in the absence of genetic conditions associated with hyperparathyroidism. Age of onset of hyperparathyroidism and absence of other endocrine abnormalities clinically was reassuring, however; further biochemical and genetic testing will be considered in this patient. Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m.

Robotic-assisted parathyroidectomy via transaxillary approach: feasibility and learning curves.

There have been few reports of robotic-assisted transaxillary parathyroidectomy in the literature. We aim to report our experience with robotic-assisted transaxillary parathyroidectomy for primary hyperparathyroidism (PHPT) in the Western population. A retrospective study was performed from July 2010 through July 2019 at two institutions, one in the United States and one in France. Demographic characteristics and perioperative data were collected for all patients undergoing robotic-assisted transaxillary parathyroidectomy by a single surgeon at each institution. A linear regression model was developed to describe the learning curve for this procedure at each institution. One-hundred and two patients with PHPT were included with a median age of 55.6±12.4 years and median body mass index (BMI) of 25.5±6.1 kg/m2. The majority of patients were female (80.4%). Median total operative time was 116±53 minutes. Minor complications were reported in 2 patients (1.96%), and one case was converted to a trans-cervical approach (TCA) for four-gland exploration. Median patient follow-up time was 6.5±12.2 months, and disease recurrence was reported in one patient. Calculated learning curves showed that one surgeon achieved proficiency by the eighth case, and the other achieved proficiency by the fourteenth case. This is the largest reported experience of robotic-assisted transaxillary parathyroidectomy for PHPT in the Asian and Western population. Analysis of the procedural learning curve demonstrates that proficiency in this technique was achieved after performance of less than 15 surgeries. This procedure is safe and feasible in the hands of experienced surgeons for select patients with localized disease.

Primary Hyperparathyroidism: To Evaluate Benefit of Ultrasound and Tc99m-SESTAMIBI Scan in Localizing Abnormal Parathyroid Gland Before Surgery, in a Secondary Care Hospital.

IntroductionPrimary hyperparathyroidism is a common endocrine condition requiring parathyroidectomy for curative management. Localization of parathyroid gland by ultrasound and Tc99m-SESTAMIBI is important to opt for less invasive and comparatively lower complication risk surgery minimal invasive parathyroidectomy (MIP) instead of four-gland exploration surgery.AimTo evaluate ultrasound and Tc99m-SESTAMIBI in localization of abnormal parathyroid gland before surgery.Method and materialsAll patients of primary hyperparathyroidism (PHPT) that presented to a secondary care hospital (endocrinology department) from 2015-2019 were recruited retrospectively from electronic fusion system of hospital. Results of ultrasound parathyroid and Tc99m-SESTAMIBI done for localization of abnormal parathyroid gland were analyzed.ResultsTotal PHPT patients recruited were 59, mean age 64.2 years, male 11 (18.64%) and female 48 (81.3%). Ultrasound parathyroid was done in 44 patients, Tc 99m-SESTAMIBI was done in 31, both tests were done in 31 patients. Combined concordant adenoma in both tests was seen in 11 (35%) cases which can opt for minimal invasive parathyroidectomy (MIP) with confidence whereas 65% of cases would require either four-gland exploration or further testing like single-photon emission computed tomography-computed tomography (SPECT-CT) or intraoperative parathyroid hormone measurement to opt for MIP.ConclusionCombined ultrasound parathyroid and Tc 99m-SESTAMIBI scan was useful in localization of parathyroid adenoma in 11 (35%) patients that can opt for MIP which is a lower complication risk surgery whereas 20 (65%) patients would need further investigation with SPECT-CT or intraoperative parathyroid hormone measurement or four-gland exploration surgery.RecommendationThird modality of investigation such as SPECT-CT or intraoperative parathyroid hormone measurement needs evaluation so that more patients can benefit from MIP instead of four-gland exploration surgery.

Recent advances in the understanding and management of primary hyperparathyroidism.

Primary hyperparathyroidism is a hormonal disorder whose prevalence is approximately 1–2% in the United States of America. The disease has become more recognizable to clinicians in an earlier phase and, at present, patients can be diagnosed with “classic”, “normocalcemic”, “normohormonal”, or “mild, asymptomatic” primary hyperparathyroidism. Surgery, with a focused parathyroidectomy when possible, or a four-gland exploration, is the only way to cure the disease. Cure is determined by use of intra-operative parathyroid hormone monitoring with long-term cure rates ranging from 90–95%. Newer adjuncts to surgery include CT or PET imaging and near-infrared immunofluorescence. This article highlights updates in parathyroid disease and advances in parathyroid surgery; it does not provide a comprehensive summary of the disease process or a review of surgical indications, which can be found in the AAES guidelines or NIH Symposium on primary hyperparathyroidism.

Are Tc-99m-Sestamibi Scans in Patients With Secondary Hyperparathyroidism and Renal Failure Needed?

BackgroundParathyroidectomy for patients with secondary hyperparathyroidism (sHPT) generally requires a four-gland exploration. Some groups have strongly recommended routine preoperative Tc-99m-sestamibi scans; others practice scanning for only selected patients. To determine the utility of sestamibi scans in this patient population, we reviewed our experience. MethodsWe performed a retrospective review of patients who underwent parathyroidectomy for sHPT by one surgeon between 2000 and 2018. Data reviewed included patient demographics, laboratory results, pathology and radiology reports, and clinical and operative notes. ResultsOf the 72 patients in the cohort, mean age was 47.2 ± 15.6, and 50% were female. The preoperative mean calcium and parathyroid hormone levels were 9.6 ± 1.1 mg/dL and 1192.1 ± 914.1 pg/mL, respectively. Sestamibi scans were performed in 21 patients (29%). Of these, 17 were reoperative cases. Of all sHPT patients, 27.8% had ectopic glands. In the sestamibi cohort, only four patients had ectopic glands identified on the scan. Among the 51 patients without preoperative imaging, 16 had ectopic glands (26.2% of nonimaged patients). All these 16 ectopic glands were found by the surgeon at the time of operation without the need for preoperative imaging. All patients in the series were cured with a minimum follow-up of 6 mo. ConclusionsEctopic parathyroid glands are commonly seen in patients undergoing parathyroidectomy for sHPT. The majority of ectopic glands were successfully identified during the operation without preoperative sestamibi scan. Therefore, routine preoperative Tc-99m-sestamibi scans are not needed for successful parathyroidectomy for sHPT.

SUN-494 Multiple Ectopic Parathyroid Foci: An Unexpected Finding Leading to Primary Hyperparathyroidism

Background: A patient with severe hypercalcemia and extremely elevated PTH levels found to have multiple foci of ectopic parathyroid tissue. Clinical Case: A 60-year-old female with a history of hypothyroidism and hypertension was transferred from another facility for evaluation for a parathyroidectomy. Vital signs were within normal limits. Initial evaluation revealed a corrected calcium of 8.2 mg/d, albumin level of 2.4 g/dL (n 3.2 - 4.6 g/dL). Creatinine was within normal limits. PTH level of 908 pg/dL (n 9.0 - 77.0 pg/dL), 25-vitamin D level of 15 ng/mL. The patient was recently admitted to another facility for septic shock secondary to UTI. She was found to have bilateral renal stones, for which she underwent ureteral stent placement. Further workup revealed severe hypercalcemia of 20.0 mg/dL and a PTH level >2,500 pg/dL. She was treated with IV fluids, bisphosphonates, calcitonin and cacimimetics. She was discharged with the plan for an outpatient parathyroidectomy. Prior to the parathyroidectomy, the patient was readmitted for acute respiratory failure. A parathyroid NM scan was performed and revealed no persistent uptake to suggest a parathyroid adenoma. She was subsequently transferred and admitted to our facility.During the admission, ENT and endocrinology were consulted. A NM scan was repeated, which showed a questionable right lower pole thyroid focus concerning for a parathyroid adenoma. 4D CT scan had concordant findings. Due to the exceedingly elevated PTH level, there was concern for parathyroid carcinoma. Patient underwent right thyroid lobectomy, parathyroidectomy with four-gland exploration, right central neck dissection, and reimplantation of ½ left super parathyroid to the left sternocleidomastoid. After the surgery, calcium and vitamin D supplementation were initiated. Her calcium levels remained stable throughout the hospital course. Operative parathyroid pathology revealed normal parathyroid glands with no malignancy, in addition to 12 foci of ectopic parathyroid glands. Conclusion: Treatment of primary hyperparathyroidism with parathyroidectomy is efficacious in 80-97% of initial explorations. The ability to locate ectopic glands are linked to the failure or success rates. Although ectopic parathyroid glands are common (15%), multiple ectopic glands, as in this case, are rarely reported.

Operative Approach to Primary Hyperparathyroidism

We review the key components of the embryology and anatomy of the parathyroid glands. Here, minimally invasive parathyroidectomy with intraoperative adjuncts such as intraoperative parathyroid hormone monitoring, four-gland exploration, subtotal parathyroidectomy, total parathyroidectomy with autotransplantation, and cyropreservation are described. The incidence of postoperative complications and the technical aspects of parathyroid surgery are delineated. This review contains 3 figures, 1 tables, and 17 references. Key Words: cryopreservation, hyperparathyroidism, minimally invasive parathyroidectomy parathyroidectomy, pharyngeal pouch, recurrent laryngeal nerve, subtotal parathyroidectomy, total parathyroidectomy

Operative Approach to Primary Hyperparathyroidism

We review the key components of the embryology and anatomy of the parathyroid glands. Here, minimally invasive parathyroidectomy with intraoperative adjuncts such as intraoperative parathyroid hormone monitoring, four-gland exploration, subtotal parathyroidectomy, total parathyroidectomy with autotransplantation, and cyropreservation are described. The incidence of postoperative complications and the technical aspects of parathyroid surgery are delineated. This review contains 3 figures, 1 tables, and 17 references. Key Words: cryopreservation, hyperparathyroidism, minimally invasive parathyroidectomy parathyroidectomy, pharyngeal pouch, recurrent laryngeal nerve, subtotal parathyroidectomy, total parathyroidectomy

Highly specific preoperative selection of solitary parathyroid adenoma cases in primary hyperparathyroidism by quantitative image analysis of the early-phase Technetium-99m sestamibi scan.

Highly specific preoperative localizing test is required to select patients for minimally invasive parathyroidectomy (MIP) in lieu of traditional four-gland exploration. We hypothesized that Tc-99m sestamibi scan interpretation incorporating numerical measurements on the degree of asymmetrical activity from bilateral thyroid beds can be useful in localizing single adenoma for MIP. We devised a quantitative interpretation method for Tc-99m sestamibi scan based on the numerically graded asymmetrical activity on early phase. The numerical ratio value of each scan was obtained by dividing the number of counts from symmetrically drawn regions of interest (ROI) over bilateral thyroid beds. The final pathology and clinical outcome of 109 patients were used to perform receiver operating curve (ROC) analysis. Receiver operating curve analysis revealed the area under the curve (AUC) was calculated to be 0.71 (P=0.0032), validating this method as a diagnostic tool. The optimal cut-off point for the ratio value with maximal combined sensitivity and specificity was found with corresponding sensitivity of 67.9% (56.5-77.2%, 95% CI) and specificity of 75.0% (52.8-91.8%, 95% CI). An additional higher cut-off with higher specificity with minimal possible sacrifice on sensitivity was also selected, yielding sensitivity of 28.6% (18.8-38.6%, 95% CI) and specificity of 90.0% (69.6-98.8%, 95% CI). Our results demonstrated that the more asymmetrical activity on the initial phase, the more successful it is to localize a single parathyroid adenoma on sestamibi scans. Using early-phase Tc-99m sestamibi scan only, we were able to select patients for minimally invasive parathyroidectomy with 90% specificity.

Factors Influencing Time to Decrease in Intraoperative Parathyroid Hormone (ioPTH) Levels in Patients Undergoing Focused Parathyroidectomy (FP)

The aim of this study was to evaluate potential factors affecting the time period in which a 50 per cent parathyroid hormone (PTH) drop is observed. Eight-seven patients undergoing focused parathyroidectomy between 2011 and 2015, whose PTH values dropped to within normal range, were grouped according to whether they required > or ≤15 minutes after gland excision to achieve a 50 per cent PTH. Groups were compared according to preoperative PTH, calcium, age, glomerular filtration rate, and adenoma weight. Lower preoperative and preincision PTH levels were associated with requiring >15 minutes to achieve a >50 per cent drop in ioPTH. Time to >50 per cent ioPTH drop did not affect cure rates at one year, though a >15 minutes requirement was associated with higher serum calcium levels (P = 0.015). Lower baseline PTH and preincision PTH levels are significantly associated with a >15 minutes postexcision time to achieve a >50 per cent drop in ioPTH. Future analyses are warranted to determine whether a longer postexcision time threshold before proceeding with four-gland exploration is warranted in patients with primary hyperparathyroidism and mildly elevated preoperative PTH.

Focused parathyroidectomy without intraoperative parathormone testing is safe after pre-operative localization with 18F-Fluorocholine PET/CT

A focused surgical approach based on pre-operative localization replaced the classical four-gland exploration in patients with primary hyperparathyroidism (PHP). Sestamibi scanning and ultrasound are most often used localization modalities with reported sensitivity of 54–100% for identification of single gland disease.The aim of this study was to analyze the results of pre-operative localization with 18F-Fluorocholine PET/CT (FCh-PET) in patients with PHP.A retrospective review of 151 patients with PHP who underwent surgery after pre-operative localization with FCh-PET was performed. Only a focused parathyroidectomy without ioPTH testing had been done in patients with single adenoma on FCh-PET. Primary outcome was operative failure, defined as persistent PHP.According to pre-operative FCh-PET 126 (83,4%) patients had single adenoma, 22 (14,5%) multiglandular disease and the test was negative in only two patients. Intraoperative failure experienced 4/126 patients (3,3%) with single adenoma. Removed parathyroid glands were normal in three and hyperplastic in one patient with intraoperative failure. A limited bilateral neck exploration with ioPTH testing was used in 14/22 patients with double adenoma and a classical four-gland exploration without ioPTH testing was used in 8/22 patients with more than two pathological glands according to pre-operative FCh-PET. Intraoperative failure experienced 2/22 patients (9,1%). In two patients with negative FCh-PET a classical four-gland exploration without ioPTH testing was used and one experienced intraoperative failure.A preoperative localization with FCh-PET is a reliable test in patients with PHP. Patients with a single adenoma on FCh-PET can safely undergo a focused parathyroidectomy without ioPTH testing.

Endoscopic and robotic parathyroidectomy in patients with primary hyperparathyroidism.

Primary hyperparathyroidism (PHPT) is one of the most common endocrine disorders for which parathyroidectomy is the most effective therapy. Until late 1970s, the standard approach to parathyroidectomy was a four-gland exploration using a large skin incision. However, 80 to 85 percent of cases of PHPT are caused by a single adenoma. As such, the concept of performing a bilateral exploration in order to visualize all four glands has been argued to be excessive since in the majority of cases, there is only one abnormal gland. Focused exploration (one gland) is currently the standard technique for parathyroidectomy worldwide. Despite a rapid acceptance of minimally invasive approaches in most endocrine surgery centers, the use of an endoscope with or without the use of a robotic system to perform parathyroidectomy remains controversial. The goal of this study was to review current available data about surgical approaches using an endoscope with or without the use of a robotic system in the management of patients with PHPT. For conventional endoscopic and video assisted parathyroidectomy, several comparative studies have demonstrated some advantages in terms of reduced postoperative pain, better cosmetic results and higher patient satisfaction compared to open non-endoscopic minimally invasive parathyroidectomy. Robot-assisted transaxillary parathyroidectomy has the advantage of leaving no scar in the neck but its role has not yet been delineated clearly given the limited number of published series. Subjective postoperative cosmetic evaluation is good by concealing the scar in the axilla or infraclavicular area. However, this approach is associated with more extensive dissection than during conventional open or endoscopic neck access surgical procedures. Patients with true ectopic mediastinal parathyroid glands are good candidates for conventional or robot-assisted thoracoscopic approaches because these glands are in remote and narrow anatomical locations.

Value of Prophylactic Cervical Thymectomy in Parathyroid Hyperplasia.

In parathyroid hyperplasia (HPT), parathyroid glands within the cervical thymus are a cause for recurrence. As a result of differences in pathophysiology, variable practice patterns exist regarding performing bilateral cervical thymectomy (BCT) in primary hyperplasia versus hyperplasia from renal failure or familial disease. The objective of this study was to capture patients where thymic tissue was found with subtotal parathyroidectomy (PTX) and intended BCT, identify number of thymic supernumerary glands (SNGs), and determine overall cure rate. Retrospective review of patients with four-gland exploration and intended BCT for HPT from 2000 to 2013 was performed. Identification of thymic tissue and SNGs were determined by operative/pathology reports. Univariate analysis identified differences in cure rate for patients undergoing subtotal PTX with or without BCT. Thymic tissue was found in 52 % of 328 primary HPT (19 % unilateral, 33 % bilateral), 77 % of 128 renal HPT (28 % unilateral, 49 % bilateral), and 100 % of familial HPT (24 % unilateral, 76 % bilateral) patients. Nine percent of primary, 18 % of renal, and 10 % of familial HPT patients had SNGs within thymectomy specimens. Cure rates of primary HPT patients with BCT were 99 % compared to 94 % in subtotal PTX alone. Renal HPT cure rates were 94 % with BCT compared to 89 % without BCT. Renal HPT patients benefited most in cure when thymectomy was performed. Although the rate of SNGs found in primary HPT was lower than renal HPT, the cure rate mimicked the pattern in renal disease. Furthermore, the incidences of SNGs in primary and familial HPT were similar. On the basis of these data, we advocate that BCT be considered in primary HPT when thymic tissue is readily identified.

Minimally invasive parathyroid surgery.

Traditionally, bilateral cervical exploration for localization of all four parathyroid glands and removal of any that are grossly enlarged has been the standard surgical treatment for primary hyperparathyroidism (PHPT). With the advances in preoperative localization studies and greater public demand for less invasive procedures, novel targeted, minimally invasive techniques to the parathyroid glands have been described and practiced over the past 2 decades. Minimally invasive parathyroidectomy (MIP) can be done either through the standard Kocher incision, a smaller midline incision, with video assistance (purely endoscopic and video-assisted techniques), or through an ectopically placed, extracervical, incision. In current practice, once PHPT is diagnosed, preoperative evaluation using high-resolution radiographic imaging to localize the offending parathyroid gland is essential if MIP is to be considered. The imaging study results suggest where the surgeon should begin the focused procedure and serve as a road map to allow tailoring of an efficient, imaging-guided dissection while eliminating the unnecessary dissection of multiple glands or a bilateral exploration. Intraoperative parathyroid hormone (IOPTH) levels may be measured during the procedure, or a gamma probe used during radioguided parathyroidectomy, to ascertain that the correct gland has been excised and that no other hyperfunctional tissue is present. MIP has many advantages over the traditional bilateral, four-gland exploration. MIP can be performed using local anesthesia, requires less operative time, results in fewer complications, and offers an improved cosmetic result and greater patient satisfaction. Additional advantages of MIP are earlier hospital discharge and decreased overall associated costs. This article aims to address the considerations for accomplishing MIP, including the role of preoperative imaging studies, intraoperative adjuncts, and surgical techniques.

Preoperative imaging for focused parathyroidectomy: making a good strategy even better.

Surgical treatment for primary hyperparathyroidism (pHPT) has undergone a major paradigm shift during the last decades from bilateral cervicotomy with four-gland neck exploration to image-guided focused approaches. The primary objective of the present study was to compare the performances of parathyroid scintigraphy (PS), parathyroid ultrasonography (US), and the combination of both procedures for guiding a focused approach on the basis of modified interpretation criteria. Data from 199 patients operated for apparent sporadic pHPT and evaluated with US and PS using dual-isotope (123)I/(99m)Tc-sestamibi planar pinhole and single-photon emission computed tomography (SPECT) acqusitions were evaluated. A total of 127 patients underwent a focused approach and the remainder had bilateral cervicotomy. In 42 cases, a focused approach was not performed due to the absence of concordant results between US and PS for a single-gland abnormality. Four patients had persistent disease and three had recurrent disease. A localizing preoperative PS had a sensitivity of 93.3%, positive predictive value of 85.8%, negative predictive value of 73.0%, and accuracy of 83.4% for predicting uniglandular disease. Additional SPECT images accurately localize posterior adenomas that are often missed by US. Compared with PS, US had a lower sensitivity (P<0.01). Our imaging protocol also enabled diagnosis of multiglandular disease in 60.6%. PS using a highly sensitive dual-tracer subtraction method is the most accurate technique for directing a focused approach. PS could be sufficient for directing a focused approach in the presence of a negative US in two major circumstances: posterior locations due to acquired ectopia that could be missed by US, and previous history of thyroidectomy due to interpretation difficulties.

The utility of neck ultrasound and sestamibi scans in patients with secondary and tertiary hyperparathyroidism.

Secondary hyperparathyroidism (SHPT) and tertiary hyperparathyroidism (THPT) are disease entities in patients with chronic kidney disease that are caused by parathyroid hyperplasia. The role of preoperative localization studies in patients undergoing parathyroidectomy for these conditions remains poorly defined. To evaluate the utility of surgeon-performed neck ultrasound (US) as well as sestamibi scans in the localization of parathyroid glands in patients with SHPT/THPT. A retrospective analysis of patients with SHPT/THPT who underwent parathyroidectomy at a single institution. Results of preoperative localization studies were compared to intraoperative findings. One hundred and three patients underwent parathyroidectomy for SHPT/THPT. All patients underwent surgeon-performed neck US, while 92 (89%) underwent sestamibi scans. US failed to localize any of the parathyroids in 4 patients (3.8%), while sestamibi was negative in 11 (12%). Forty-seven ectopic glands were identified in 38 patients in whom sestamibi was performed. In five patients (13%), ectopic glands were identified by both modalities, by US only in 6 (16%), by sestamibi only in 8 (21%), and by neither study in 19 patients (50%). US showed new thyroid nodules in 19 patients (18.4 %), leading to lobectomy or thyroidectomy at the time of parathyroidectomy in 16 patients (15.5%). Pathology showed malignancy in 7 patients (6.8%). US and MIBI offer little benefit in localizing ectopic glands and rarely change the conduct of a standard four-gland exploration. Although there was a benefit of US in the assessment of thyroid nodules, in only 8.7% of patients was sestamibi of benefit in identifying ectopic glands.

Primary hyperparathyroidism after Roux-en-Y gastric bypass.

Primary hyperparathyroidism (PHPT) in the setting of previous roux-en-Y gastric bypass (RYGBP) is not well described. The diagnosis can be difficult, as secondary hyperparathyroidism (SHPT) commonly occurs in patients after RYGBP due to calcium malabsorption and vitamin D deficiency. All patients from 2000 to 2012 who underwent cervical exploration for diagnosis of primary hyperparathyroidism with history of preceding RYGBP were identified and analyzed retrospectively. Ten patients were identified. The average age was 58.4 and all patients were female. Time interval between RYGBP and cervical exploration was 67 months with median follow-up of 19 months. Average preoperative calcium was 10.8 mg/dL, PTH 155 pg/mL, and 25-vitamin-D 32 ng/mL. Eighty percent of patients presented with symptoms and 90% underwent preoperative imaging. Seventy percent underwent initial focused parathyroidectomy with 20% being converted to four-gland exploration. Seventy percent of patients had a single adenoma with two patients having multi-gland disease. Intraoperative PTH was used in seven patients with successful drop to 50% of baseline in all. Ninety percent of patients had greater then 6-month follow-up without evidence of persistent or recurrent PHPT. Average 6-month calcium was 9.3 mg/dL, PTH 73 pg/mL, and 25-vitamin-D 44 ng/ML. Four patients had evidence of persistently elevated PTH despite normalization of calcium. PHPT after RYGBP is rare but surgery with either a focused approach following successful localization or four-gland exploration is indicated when the biochemical diagnosis holds true. The presence of SHPT can make diagnosis and follow-up difficult and may predispose them to severe post-operative hypocalcemia.