Feasibility of Intraoperative Parathyroid Hormone Monitoring in Minimally Invasive Surgery

Background and Objectives There has been a long debate on whether intraoperative parathyroid hormone (IOPTH) monitoring is mandatory or not in the excision of a single abnormal parathyroid gland. The aim of this study is to suggest a new criteron of IOPTH monitoring. Subjects and Method We retrospectively analyzed 31 patients who underwent parathyroidectomy from 2005 to 2019. Patients had IOPTH not measured and those with secondary hyperparathyroidism were excluded. IOPTH was measured preoperatively (EX00), at 10 minutes (EX10) and 20 minutes (EX20) after the excision and analyzed. We determined the surgery as a ‘successful excision of lesion (SEOUL)’ when it met the following criteria: criterion 1) the level of EX10 or EX20 decreased under the upper normal or under upper limit of parathyroid hormone (65 pg/mL); criterion 2) EX20 decreased below 50% of EX00 and less than 195 pg/ mL (3 times the upper normal limit); criterion 3) multiglandular disease. Results Twenty-five patients among 31 patients were included this study (M:F=8:17). Twenty- two patients were suspected of single lesion and three patients of multiple lesions on preoperative images (99mTc-sestamibi scan, neck CT, and PET-CT). IOPTH of EX00, EX10, and EX20 were 488.92±658.74, 121.36±134.73, and 92.44±111.55 pg/mL, respectively. Sixty-four percent patients (16/25) met the criterion 1. Six patients (24%) successfully excised a lesion meeting the criterion 2. Three patients had multiglandular disease, meeting the criterion 3. Conclusion Our new criteria suggest when we could stop the procedure. If the level of IOPTH does not meet the SEOUL criteria, it means that there might be more lesions.

Preventing blind thyroid lobectomy in patients with intrathyroidal hyperfunctioning parathyroid glands with radioguided enucleation

Aim: Hyperfunctioning intrathyroidal parathyroid glands are rare and often result in thyroid lobectomy. This study examines the utility of radioguided surgery to guide enucleation of intrathyroidal parathyroids. Methods: Between December 2002 and March 2018, 2291 patients underwent parathyroidectomy by one surgeon for primary hyperparathyroidism. A total of 74 (3%) patients had an ectopic intrathyroidal parathyroid gland and underwent radioguided. Results: All of intrathyroidal parathyroid glands were localized with the gamma probe. In vivo radionuclide counts were above 120% of the background in all but three patients. All intrathyroidal parathyroids were enucleated with the guidance of the gamma probe. Conclusion: Radioguided surgery is useful for intraoperative identification of hyperfunctioning, intrathyroidal parathyroid glands. This technique allows for enucleation of the abnormal parathyroid gland, avoiding thyroid lobectomy and preserving healthy thyroid parenchyma.

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<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< 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

Patterns of disease in patients at a tertiary referral centre requiring reoperative parathyroidectomy

Introduction Reoperative parathyroidectomy is required when there is persistent or recurrent hyperparathyroidism following the initial surgery (at least 5% of parathyroidectomies nationally). By convention, ‘persistent disease’ is defined as the situation where the patient has not been cured by the first operation. The term ‘recurrent hyperparathyroidism’ is used when the patient was confirmed to be biochemically cured for six months from the first operation but has hyperparathyroidism after this date. Reoperative surgery is associated with higher rates of postoperative complications as well as a greater rate of failure to cure. The aim of our study was to review our departmental experience of reoperative parathyroidectomy, with a view to identify patterns of disease persistence and recurrence. Methods Using a departmental database, patients were identified who had undergone reoperative parathyroidectomy between 2006 and 2014. All the pre, intra and postoperative information was documented including the operative note so as to record the location of the abnormal parathyroid gland found at reoperation. Results Almost two-thirds (63%) of patients had negative, equivocal or discordant conventional imaging so secondary investigative tools were required frequently. The majority of abnormal glands were found in eutopic locations. The most common locations for ectopic glands were intrathyroidal, mediastinal and intrathymic. A third (33%) of the patients had multigland disease and over a quarter (28%) had coexisting thyroid disease. Conclusions Persistent hyperparathyroidism represents a challenging patient subgroup for which access to all radiological modalities and intraoperative parathyroid hormone monitoring are required. Patient selection for reintervention is a key determinant in the reoperation cure rate.

Preoperative parathyroid harpoon localisation: a new technique helpful in reoperative patients with persistent hyperparathyroidism

Surgery for persistent primary hyperparathyroidism remains a major challenge for surgeons and these reoperative procedures require an experienced parathyroid surgeon. The goal of reoperative surgery is to excise the abnormal parathyroid gland(s) and limit exploration to help minimise the potential complications. At least two positive and concordant localising studies should be available before reoperation because the technical difficulties in these cases make an exact localisation necessary before surgery. We describe the placement of a metallic harpoon under ultrasonography guidance as a safe, simple and inexpensive technique for localisation of the enlarged gland prior to conservative surgery.

Incidental Parathyroid Disease during Thyroid Surgery: Should We Remove Them?

Aim. Despite an incidence of parathyroid “incidentalomas” of 0.2%–4.5%, only approximately 135 cases have been reported in the literature. We present eight patients in whom an incidental abnormal parathyroid gland was found during routine thyroid surgery. We have reviewed the literature and postulate whether these glands could represent further evidence of a preclinical stage of primary hyperparathyroidism. Methods. A retrospective analysis of all 236 thyroid operations performed by a single surgeon was performed to identify patients in whom abnormal parathyroid tissue was removed at surgery. Results. 8/236 patients (3.39%) had a single macroscopically abnormal parathyroid gland removed and sent for analysis. Seven patients were found to have histological evidence of a parathyroid adenoma or hyperplasia. None of the patients had abnormal serum calcium detected preoperatively. Postoperatively, four patients had normal calcium, three had temporary hypocalcaemia and one refused followup. No patients had recurrent laryngeal nerve impairment. Conclusions. Despite the risk of removing a histologically normal gland, we believe that when parathyroid “incidentalomas” are found during surgery they should be excised and sent for histological analysis. We have found this to be a safe procedure with minimal morbidity to the patient. As the natural history of primary hyperparathyroidism is better understood, these glands found in normocalcaemic patients may in fact represent the early or preclinical phase of the disease. By removing them at the original operation, the patient is saved redo neck surgery with its high complication rate as or when clinically apparent primary hyperparthryoidism develops in the future.