Intraoperative Parathyroid Hormone Research Articles

Normocalcaemic primary hyperparathyroidism: what is the role of parathyroid surgery?

Primary hyperparathyroidism (PHPT) is classically associated with both an elevated or ‘inappropriately normal’ parathyroid hormone (PTH) level and raised serum calcium. However, in clinical practice, increasing numbers of patients present with raised PTH but normal serum calcium, renal function and vitamin D; this is known as normocalcaemic PHPT (nPHPT). Studies investigating the clinical presentation of this condition have shown that patients may present with hypertension, nephrolithiasis, impaired glucose tolerance, osteoporosis and fragility fractures. The prevalence of such complications in nPHPT is similar to that in classical hypercalcaemic PHPT (hPHPT). Although the National Institute for Health and Care Excellence (NICE) have developed guidelines for the management of PHPT generally, a consensus is yet to be reached on the optimal management of nPHPT specifically. A review of the literature on parathyroidectomy in the treatment of nPHPT revealed that nPHPT patients were more likely to present with multi-glandular disease and significantly less nPHPT patients had an intra-operative PTH fall of >50% compared with those with hPHPT. These findings demonstrate that patients with nPHPT are more likely to receive bilateral neck explorations and require remedial surgery compared with hPHPT patients. Following surgery, improvements in bone mineral density (BMD) and renal stones are generally observed in those with nPHPT. Where surgery is not possible, medical management with alendronate has been shown to be effective in nPHPT patients. Given the higher incidence of multi-gland disease and greater possibility of remedial surgery in nPHPT, careful consideration of risks and benefits should be made on an individualised basis and surgery should be performed by surgeons experienced in four gland exploration.

Delayed sampling of intraoperative parathormone may be unnecessary during parathyroidectomy in kidney-transplanted and dialysis patients.

Introduction:Some authors advise in favor of delayed sampling of intraoperative parathormone testing (ioPTH) during parathyroidectomy in dialysis and kidney-transplanted patients. The aim of the present study was to evaluate the intensity and the role of delayed sampling in the interpretation of ioPTH during parathyroidectomy in dialysis patients (2HPT) and successful kidney-transplanted patients (3HPT) compared to those in single parathyroid adenoma patients (1HPT).Methods:This was a retrospective study of ioPTH profiles in patients with 1HPT, 2HPT, and 3HPT operated on in a single institution. Samples were taken at baseline ioPTH (sampling at the beginning of the operation), ioPTH-10 min (10 minutes after excision of the parathyroid glands), and ioPTH-15 min (15 minutes after excision of the parathyroid glands). The values were compared to baseline.Results:Median percentage values of ioPTH compared to baseline (100%) were as follows: 1HPT, ioPTH-10 min = 20% and ioPTH-15 min = 16%; 2HPT, ioPTH-10 min = 14% and ioPTH-15 min = 12%; 3HPT, ioPTH-10 min = 18% and ioPTH-15 min = 15%.Discussion:The reduction was equally effective at 10 minutes in all groups. In successful cases, ioPTH decreases satisfactorily 10 minutes after parathyroid glands excision in dialysis and transplanted patients, despite significant differences in kidney function. The postponed sampling of ioPTH appears to be unnecessary.

Predictors of Postoperative Hypocalcemia after Total Thyroidectomy: The Role of a Single Intraoperative Rapid PTH

Postoperative hypocalcemia (PoHC) is the most common complication of total thyroidectomy (TT). The availability of a reliable predictor of PoHC would allow early calcium supplementation, avoiding hypocalcemia, and potentially decreasing hospital stay.

A Review of Parathyroid Surgery for Primary Hyperparathyroidism from the United Kingdom Registry of Endocrine and Thyroid Surgery (UKRETS)

BackgroundThe United Kingdom Registry of Endocrine and Thyroid Surgeons is a national database holding details on > 28,000 parathyroidectomies.MethodsAn extract (2004–2017) of the database was analysed to investigate the reported efficacy, safety and use of intra-operative surgical adjuncts in targeted parathyroidectomy (tPTx) and bilateral neck exploration (BNE) for adult, first-time primary hyperparathyroidism (PHPT).Results50.9% of 21,738 cases underwent tPTx. Excellent short-term (median follow-up 35 days) post-operative normocalcaemia rates were reported overall (tPTx 96.6%, BNE 94.5%, p < 0.05) and in image-positive cases (tPTx 96.7%, BNE 96%, p < 0.05). Intra-operative PTH improved overall normocalcaemia rates (tPTx 97.8% vs 96.3%, BNE 95% vs 94.4%: both p < 0.05). Intra-operative nerve monitoring reduced vocal cord (VC) dysfunction in image-positive tPTx, but not in BNE (97.8% vs 93.2%, p < 0.05). Complications were higher following BNE (7.4% vs 3.8%, p < 0.05), especially hypocalcaemia (5.3% vs 2%, p < 0.05). There was no difference in rates of subjective dysphonia following tPTx or BNE (2.4% vs 2.3%, p > 0.05), nor any difference in VC dysfunction when formally examined (4.9% vs 4.1%, p > 0.05).ConclusionsIn image-positive, first time, adult PHPT cases, tPTx is as safe and effective as BNE, with both achieving excellent short-term results with minimal complications.

Etiology and Pathophysiology of Hypoparathyroidism: A Narrative Review.

The approach utilized a systematic review of the medical literature executed with specifically designed criteria that focused on the etiologies and pathogenesis of hypoparathyroidism. Enhanced attention by endocrine surgeons to new knowledge about parathyroid gland viability are reviewed along with the role of intraoperative parathyroid hormone (ioPTH) monitoring during and after neck surgery. Nonsurgical etiologies account for a significant proportion of cases of hypoparathyroidism (~25%), and among them, genetic etiologies are key. Given the pervasive nature of PTH deficiency across multiple organ systems, a detailed review of the skeletal, renal, neuromuscular, and ocular complications is provided. The burden of illness on affected patients and their caregivers contributes to reduced quality of life and social costs for this chronic endocrinopathy. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Correlation of perioperative biochemical variables with single adenoma weight in patients with primary hyperparathyroidism

BackgroundSingle parathyroid adenoma is the main cause of primary hyperparathyroidism (PHPT), with surgery remaining the gold standard for its treatment. The ability to preoperatively predict the parathyroid adenoma size and could facilitate the decision about the extent of surgical exploration. It is reasonable to hypothesize that the perioperative levels of PHPT-related variables (i.e. calcium, parathormone, phosphate) may predict the adenoma weight or/and demonstrate whether the adenoma is successfully removed or not. Aim of this study is to explore the relationship between perioperative biochemical values and adenoma weight. Secondarily, we investigated the relationship between adenoma weight and uni-/bilateral neck exploration.MethodsRetrospective study of all patients undergone surgery for primary hyperparathyroidism due to single adenoma in a tertiary university hospital in Germany during a 6-year period. Following variables were analyzed: preoperative serum calcium, phosphorus and parathormone, intraoperative parathormone before and after adenoma excision, intraoperative PTH decrease, postoperative serum calcium and parathormone (PTHpostop—pg/ml), calcium and PTH decrease. Bivariate correlations were calculated by the Spearman's correlation test at the 95% significance level.ResultsA total of 339 patients were included in the study. The median age of the patients was 60 years (range 21–90) and 77% were females. The median adenoma weight was 1 g (range 0.1–11). Adenoma weight correlated strong with maximum adenoma diameter (r = 0.72, p < 0.05), moderate with preoperative parathormone (r = 0.44) and parathormone decrease (r = 0.27), whereas there was no correlation with the intraoperative PTH decrease (r = 0.02). There was also a borderline (moderate to weak) correlation with pre- and postoperative calcium levels (r = 0.21 and r = 0.23 respectively) and a negative borderline correlation with phosphorus (r = − 0.21). Patients who required bilateral neck exploration, had significantly lighter adenomas (medianweight 0.8 g vs 1.1 g, p = 0.005).ConclusionsWe conclude that preoperative PTH levels may only serve as an approximate guide to adenoma weight, as direct preoperative prediction is not possible. Serum calcium levels, PTH and calcium decrease correlate only weak with adenoma weight. Patients who require bilateral neck exploration, have significantly (20–25%) lighter adenomas.

Estudios preoperatorios coincidentes para el diagnóstico de hiperparatiroidismo primario por adenoma simple: ¿podemos evitar la PTH intraoperatoria?

IntroductionWe aim to determine the utility of intraoperative parathyroid hormone (IOPTH) monitoring in patients with matching preoperative ultrasound and mibi SPECT for primary hyperparathyroidism for a single adenoma. MethodsAll patients who underwent minimally invasive parathyroidectomy (MIP) for pseudohypoparathyroidism (PHP) for a single parathyroid adenoma, were included. An Ultrasound and mibi SPECT were performed in all patients. We defined matching studies when both coincided in the localization of the adenoma. IOPTH was performed in all patients and analyzed in three occasions: a baseline measurement at the anesthetic induction, immediately before, and 15 minutes after gland excision. Success was defined during the third measurement as a drop of IOPTH of at least 50%compared to the previous maximum value after gland excision. Demographics, intraoperative, postoperative variables and the utility of IOPTH monitoring were analyzed. ResultsA total of 218 MIP were performed. The average age was 60.1 years and 85% were female. Preoperative ultrasound and mibi SPECT coincided 100%. When the adenoma was localized, 15 minutes after its excision, IOPTH did not decrease in 9 patients (4.2% OR 1.9% - 7.69%); all of them underwent a bilateral neck exploration. The added-value of IOPTH accuracy for disease cure was 3.6%. There was a 99% of cure rate. The mean surgical time was 66.4 minutes and the waiting time for the third IOPTH result was 31minutes. Performing IOPTH monitoring made the surgery about twice more expensive. ConclusionsPreoperative matching ultrasound and mibi SPECT for parathyroid adenoma localization in PHP, could avoid IOPTH monitoring in minimally invasive parathyroidectomies.

Use of Intraoperative Parathyroid Hormone in Minimally Invasive Parathyroidectomy for Primary Hyperparathyroidism

Intraoperative parathyroid hormone (ioPTH) is a surgical adjunct that has been increasingly used during minimally invasive parathyroidectomy (MIP). Despite its growing popularity, to our knowledge a meta-analysis comparing MIP with ioPTH vs MIP without ioPTH has not yet been conducted. To evaluate the safety and efficacy of MIP with ioPTH for treatment of primary hyperparathyroidism. A systematic search of the databases PubMed, Embase, Scopus, Web of Science, and Cochrane Collaboration was performed to identify studies that compared MIP with and without ioPTH. Data were analyzed between August and September 2019. Inclusion criteria consisted of randomized clinical trials and observational studies with a retrospective/prospective design, comparing MIP using ioPTH vs MIP not using ioPTH for treatment of primary hyperparathyroidism. Eligible studies had to present odds ratio (OR), risk ratio, or hazard ratio estimates (with 95% CI), standard errors, or number of events necessary to calculate these for the outcome of interest rate. Studies involving patients with secondary or tertiary hyperparathyroidism or those with multiple endocrine neoplasia syndrome were excluded. Two reviewers independently reviewed the literature according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. Dichotomous variables were pooled as ORs while continuous variables were compared using weighted mean differences. Quality assessment was performed using the Newcastle-Ottawa Scale. The primary outcome was rate of cure. Secondary outcomes included need for reoperation, need for bilateral neck exploration, morbidity, and length of surgery. A total of 12 studies, involving 2290 patients with primary hyperparathyroidism, were eligible for inclusion. The median (SD) age of participants was 60.1 (11.8) years and 77.3% of participants were women. The median Newcastle-Ottawa score was 7. Patients who underwent MIP with ioPTH had higher cure rates (OR, 3.88; 95% CI, 2.12-7.10; P < .001). There was a greater need for reoperation in the group of patients who had surgery without ioPTH (OR, 0.40; 95% CI, 0.19-0.86; P = .02). There was a trend toward longer operating times/increased duration of surgery in the ioPTH group; however, this did not reach statistical significance (weighted mean difference, 21.62 minutes; 95% CI, -0.93 to 44.17 minutes; P = .06). The use of ioPTH was associated with higher rates of bilateral neck exploration (OR, 3.55; 95% CI, 1.27-9.92; P = .02). Use of ioPTH is associated with higher cure rates for patients with primary hyperparathyroidism undergoing MIP. Minimally invasive parathyroidectomy performed without ioPTH is associated with less conversion to bilateral neck exploration at initial surgery but with lower cure rates and an increased risk for reoperation. PROSPERO identifier: CRD42020148588.

Primary hyperparathyroidism

Primary hyperparathyroidism Abstract. Primary hyperparathyroidism is a common endocrine disease that comes along with a disruption of the calcium homeostasis and is accompanied by a variety of downstream disorders. These are often overlooked as patients present with a multitude of unspecific symptoms or may even be asymptomatic. The diagnosis of primary hyperparathyroidism can be made with the determination of calcium and parathyroid hormone levels, including the measurement of calcium in the 24-hours urine. The operation is the only therapy to cure primary hyperparathyroidism. To successfully conduct focused parathyroidectomy an accompanying visual imaging methodology is of great value and improves the operation success rate. Furthermore, an intraoperative parathyroid hormone monitoring is applied. A bilateral neck exploration technique is applicable in selected cases. The endocrine surgical expertise is pivotal in particular for re-operations, hereditary primary hyperparathyroidism and carcinomas. If surgery is not possible, a medication-based therapy is applied. This medical therapy requests a continuous therapy progress monitoring. In conclusion, to treat primary hyperparathyroidism an interdisciplinary team approach with endocrinologists and endocrine surgeons shows the best results.

Intraoperative Fine Needle Aspiration Parathyroid Hormone Assay Can Be Used as an Alternative to Frozen Section Analysis for the Identification of Parathyroid Tissue

Abstract Introduction/Objective Histologic frozen section analysis is typically used for parathyroid tissue identification during parathyroidectomy when needed, in conjunction with a rapid intraoperative plasma parathyroid hormone (PTH) assay to confirm falling levels of circulating PTH after parathyroid excision. As an alternative to frozen section consults, we hypothesize that automated analysis of intraoperative fine needle aspiration (ioFNA) tissue samples using a rapid PTH immunoassay can accurately identify parathyroid tissue and reduce the need for frozen section consults. Methods A rapid PTH immunoassay (Elecsys PTH STAT; Roche Diagnostics, Indianapolis, IN), currently used for intraoperative plasma samples, was validated for FNA samples on a Cobas® e411 using tissue aspirates of ex vivo parathyroid and control specimens rinsed in 1mL saline. ioFNA PTH results during parathyroidectomy were then prospectively assessed for accuracy over a 4-month period by comparing values to final histopathologic diagnoses. The number of frozen section consults requested was compared to a 5-month period prior to the availability of the ioFNA PTH assay. Results Ninety patients underwent parathyroidectomy (128 excised parathyroids) during the study period, performed by a single experienced endocrine surgeon. Indications included primary (81/90), tertiary (5/90), and recurrent (4/90) hyperparathyroidism. Thirty-nine cases (55.5 excised parathyroids) were performed after the availability of the ioFNA PTH assay. ioFNA samples were sent for PTH analysis in 7/39 cases (18%; 12 samples total) and had a sensitivity/specificity of 100% (parathyroid [n=7] PTH values 1968 - &amp;gt;5000pg/mL; non-parathyroid [n=5] PTH values &amp;lt;2 - 16pg/mL). Parathyroidectomies requiring frozen section consult significantly decreased from 41% (21/51 cases; 40 specimens) to 10% (4/39 cases; 9 specimens) with the availability of the ioFNA PTH assay (p&amp;lt; 0.05, Fisher exact test). Conclusion Analysis of ioFNA tissue samples using an automated rapid PTH immunoassay can accurately identify parathyroid tissue and can be used as an alternative to frozen section consult when needed.

Minimally invasive parathyroidectomy guided by intraoperative parathyroid hormone monitoring (IOPTH) and preoperative imaging versus bilateral neck exploration for primary hyperparathyroidism in adults.

Minimally invasive parathyroidectomy guided by intraoperative parathyroid hormone monitoring (IOPTH) and preoperative imaging versus bilateral neck exploration for primary hyperparathyroidism in adults.

Tackling the wanderer: the mouse parathyroids

&lt;p&gt;Parathyroid surgery in aching, groaning, moaning, presentation has a successful outcome with intraoperative PTH descalating to less than 50% of the preoperative value. The inferior parathyroids are commonly not at the expected location with respect to the thyroids. Surgical pointers and wide exposure are the key to quick access with minimal collateral tissue trauma. &lt;/p&gt;

European multicentre study on outcome of surgery for sporadic primary hyperparathyroidism.

International multicentre outcome studies of surgery for primary hyperparathyroidism (pHPT), especially for rate of conversion to bilateral neck surgery and persistent hypercalcaemia, are scarce. Eurocrine® is a European database for endocrine surgery. Data are entered according to predefined data fields. Outcomes for patients who underwent first surgery for sporadic pHPT were analysed. Multivariable analysis was performed to identify risk factors for adverse outcome using Cox regression with constant follow-up. A total of 5861 patients were registered between 2015 and 2018. Preoperative localization procedures were used in most patients, with moderate sensitivity. Intraoperative parathyroid hormone (ioPTH) measurement was used in three-quarters of patients. Bilateral surgery was performed in 1574 patients (26·9 per cent). Among 4683 patients (79·7 per cent) for whom unilateral or focused operation was planned, the procedure was converted to bilateral surgery in 396 (8·5 per cent). The risk of conversion decreased with the use of ioPTH monitoring (relative risk (RR) 0·77). Persistent hypercalcaemia was registered in 253 patients (4·3 per cent), and was less likely with the use of two (RR 0·55) or three (RR 0·44) localization procedures. In patients with a concordant localized single lesion, the rate of persistent hypercalcaemia was 2·5 per cent. The risk of persistent hypercalcaemia decreased with the use of ioPTH measurement, but was increased in patients with negative localization procedures and conversion to bilateral surgery. The use of ioPTH measurement decreased the risk of conversion and persistent hypercalcaemia. The use of two or three localization procedures decreased the risk of persistent hypercalcaemia; in patients with a concordant single lesion, the risk of persistent hypercalcaemia was low.

Data on length of parathyroidectomy surgery and intraoperative parathyroid hormone (PTH) assay turnaround times following a switch in the location for intraoperative PTH testing from near point-of-care to central laboratory.

Intraoperative monitoring of parathyroid hormone (PTH) is commonly used during parathyroidectomies. There are a number of practical challenges in achieving rapid turnaround time (TAT) for intraoperative PTH testing, whether the testing is performed point-of-care, near point-of-care, or in a central clinical laboratory. In the related research article, we analyzed a decade of data from 3025 intraoperative PTH tests on 897 unique patients. Of these, 1787 tests on 514 unique patients (375 female, 139 male) occurred while intraoperative PTH measurement was done as near point-of-care testing; the remaining 1238 tests on 383 unique patients (282 female, 101 male) occurred after a switch to intraoperative PTH measurement by the hospital central laboratory. The data in this article provides the patient age, gender, location of surgery (main operating rooms vs. ambulatory surgery center), incision to close time for surgery, and operation start to end times. For the central laboratory testing, additional data are provided for the intraoperative PTH TAT. The analyzed data is provided in the supplementary tables included in this article. Plots of operation start and end times are also included. The dataset reported is related to the research article entitled “Evaluation of Switch from Satellite Laboratory to Central Laboratory for Testing of Intraoperative Parathyroid Hormone” [D. Jacob, G. Lal, D.R. Voss, T. Bebber, S.R. David, J. Kulhavy, S.L. Sugg, A.E. Merrill, M.D. Krasowski, Evaluation of Switch from Satellite Laboratory to Central Laboratory for Testing of Intraoperative Parathyroid Hormone, Pract. Lab. Med. (2020) 22: e00176] [1]

Evaluation of switch from satellite laboratory to central laboratory for testing of intraoperative parathyroid hormone

ObjectivesThe aim of this study was to evaluate testing turnaround time (TAT) and incision to close time in parathyroid surgeries before and after switching intraoperative parathyroid hormone (PTH) testing from a near point of care location to a central clinical laboratory. Design and MethodsThis retrospective study covered a ten-year period. Both testing locations used the same Roche Diagnostics PTH immunoassay but on different analyzers. The predominant site for surgeries was the main operating rooms (ORs) in an adjacent building, with a limited number of parathyroid surgeries performed at a more distant ambulatory surgery center (ASC). Under ideal conditions, TAT for near point-of-care testing was 20 ​min, although multiple factors could increase TAT. Incision to close time from the electronic health record was used to define time of surgery. ResultsA total of 897 unique patients were identified for which 3031 orders for intraoperative PTH were placed (383 unique patients and 1244 orders after switch in testing site). The average total TAT times for testing (mean ​± ​SD) in the central laboratory were 23.9 ​± ​16.0 ​min (median, 22 ​min) for all specimens, 22.8 ​± ​7.9 ​min (median, 21 ​min) for main OR specimens, and 26.4 ​± ​7.1 ​min (median, 25 ​min) for ASC specimens. Incision to close time for parathyroidectomies showed decreases in mean, median, and standard deviation following testing change. ConclusionsSurgery time for parathyroidectomies may remain consistent or decrease if intraoperative PTH testing is moved from a near point of care to a central laboratory.

Mediastinal Videothoracoscopic Parathyroidectomy for Primary Sporadic Hyperparathyroidism—a Case Series Analysis

Primary hyperparathyroidism is one of the commonest endocrine diseases requiring surgical parathyroidectomy for its cure. Surgical excision through conventional open neck approach and sternotomy/thoracotomy for mediastinal parathyroid adenomas not accessible through neck is the treatment of choice. In this context, we evaluated the feasibility and safety of a thoracoscopic technique for mediastinal parathyroidectomy. This is a case series analysis conducted at a tertiary care endocrine surgery department, between May 2016 and August 2019. We employed a novel thoracoscopic route for parathyroidectomy in biochemically diagnosed sporadic primary hyperparathyroidism and radiologically localized mediastinal parathyroid tumours. All the clinical, investigative, operative, pathological and postoperative data were collected from our prospectively filled database. Statistical analysis was performed with SPSS 20.0 version. Under general anaesthesia, access to chest was obtained with 3 ports (three 10 mm triangulated port sites through 3rd, 4th and 5th intercostal spaces) insufflated with 6 mmHg CO2 (carbothorax) for working space. Mediastinal pleura was opened overlying the adenoma, internal mammary vein was clipped and meticulous dissection was performed to devascularise the lesion, without breaching its capsule. Excised specimen was delivered through one of the ports after placing it in custom-made endobag. Out of the 67 hyperparathyroidism cases operated during the study period, 6 (9%) were operated by this technique. Mean operative time was 142.5 SD 14.5 min (105–170). The postoperative course was uneventful with no mortality, persistent hypercalcemia or recurrent laryngeal nerve palsy. Cure and diagnosis were confirmed by > 50% fall in intraoperative serum parathyroid hormone levels and histopathology (all were benign solitary adenomas). Through this study, we propose that our thoracoscopic mediastinal parathyroidectomy is a feasibly safe approach for primary sporadic hyperparathyroidism.

Critical analysis of the intraoperative parathyroid hormone decrease during parathyroidectomy for secondary and tertiary hyperparathyroidism

BackgroundThis study aims to determine whether intraoperative parathyroid hormone monitoring helps to predict early surgical outcomes in patients with renal hyperparathyroidism and evaluate the impact on decision making during surgery. MethodsA prospective study was conducted. Serial samples of the intraoperative parathyroid hormone were collected; 2 of these were taken before the excision, and 2 were taken after the planned parathyroid resection (10 minutes and 15 minutes). We tested the criterion of an intraoperative parathyroid hormone percentage decay ≥80% of the highest value of the basal samples as a predictor of success. ResultsOf the 228 patients, parathyroidectomy achieved success in 92.1%. In patients with secondary hyperparathyroidism, the failure group showed a tendency to stabilize or even increase the intraoperative parathyroid hormone values from the 10-minute measure (577 pg/mL) to the 15-minute measure (535 pg/mL) (P = .903). Conversely, intraoperative parathyroid hormone continued to drop in those with a successful outcome: 245 pg/mL (10 minutes) and 206 pg/mL (15 minutes) (P < .001). The failure group had a significantly lower percentage decay (P < .001) from baseline when compared with the success group. The intraoperative parathyroid hormone influenced the surgical management in up to 7% of the cases. The intraoperative parathyroid hormone dosage method showed an accuracy of 86%, a sensitivity of 88%, and specificity of 67%. ConclusionIn patients with renal hyperparathyroidism undergoing parathyroidectomy, the use of intraoperative parathyroid hormone may help to predict an early therapeutic outcome with high sensitivity and accuracy by indicating the operation's success when there is an 80% reduction of baseline intraoperative parathyroid hormone 15 minutes after removal of the enlarged glands, an associated continuous decrease in serum intraoperative parathyroid hormone levels between 10 and 15 minutes, and achievement of plasma target values <500 pg/mL.

Histologic hypercellularity in a biopsied normal parathyroid gland does not correlate with hyperfunction in primary hyperparathyroidism

BackgroundAbout 15% of patients with primary hyperparathyroidism have multiglandular disease, thus during resection of an apparent single adenoma, a visibly normal parathyroid may be identified and biopsied. Using long-term biochemical follow-up, we examined whether normal parathyroid hypercellularity correlates with multiglandular disease or primary hyperparathyroidism recurrence. MethodsWe reviewed all patients who from 2001 to 2015 had an initial operation for sporadic primary hyperparathyroidism with removal of 1 gland, routine normal parathyroid biopsy, intraoperative parathyroid hormone monitoring, and follow-up of ≥3 years. Recurrence was defined by hypercalcemia after documented cure at 6 months, and hypercellularity by standard histologic criteria. ResultsOf 134 patients with mean follow-up of 9.4 years (range, 3.1−15.9), 132 (98.5%) exhibited cure at 6 months. Two had initial failure, and 8 of 132 (6.1%) developed recurrent hyperparathyroidism (mean 5.8 y, range 4−10.6). The normal parathyroid was hypercellular in 14 of 132 (10.6%) of the cured patients, and this rate did not differ for those with long-term cure (12/124, 9.7%) versus recurrence (2/8, 25%, P = .2). The positive predictive value of normal parathyroid hypercellularity for recurrence was low (14.3%), and the negative predictive value of normal parathyroid normocellularity was high (94.9%). ConclusionDuring the initial operation for primary hyperparathyroidism, 10% of normal parathyroids are hypercellular, but this does not signify missed multiglandular disease. In contrast, normal parathyroid normocellularity has high predictive value for durable cure (95%), slightly better than visual identification of a second normal parathyroid (94%).

Radio navigation and photodynamic methods for intraoperative visualization of the parathyroid glands (review of literature)

Intraoperative identification of healthy parathyroid and parathyroid adenomas facilitate a favorable outcome of surgical treatment of patients with parathyroid diseases and various hyperparathyroidism’s forms. In doing so, it is important to preserve the entire parathyroid tissue, since unintentional damaging, removal or devascularization leads to the most common development of complication – hypoparathyroidism, which occasionally becomes permanent. Although, in case of surgical treatment of patients with hyperparathyroidism, the removal of the whole pathologically altered tissue is needed in order to avoid the persistence and recurrence hyperparathyroidism, as confirmed by intraoperative and postoperative parathyroid hormone examination. Up to recent time, surgeons could had relied only on pre-surgical localization of hyperfunctioning parathyroid glands, thorough knowledge of front neck anatomy and personal experience, which wasn’t always reliable to recognize the parathyroids intraoperatively and differentiate the healthy parathyroid tissue from adenoma. To solve these problems, the auxiliary navigation and visualization methods, based on application of radiopharmaceutical and fluorescent agents, tropic to parathyroid tissue, are being actively implemented to endocrine surgery nowadays. The comparative characteristic of modern methods for intraoperative visualization of the parathyroid glands, based on the worldwide literature data, is represented in this article.

Measurement of the AST to LD Ratio in Parathyroid Tissue Suspension Can Precisely Differentiate a Hyperfunctioning Parathyroid.

Frozen section of excised tissue is used to confirm removal of the etiology of primary hyperparathyroidism in the current era of intraoperative parathyroid hormone measurement and provides safeguards for surgeons. We recently reported that the aspartate aminotransferase (AST)/lactate dehydrogenase (LD) ratio in tissue suspension can accurately distinguish normal parathyroid tissue from other tissues. Therefore, we hypothesized that this ratio may also be applied to distinguish hyperfunctioning parathyroid tissue (HPT) from other tissues. We prospectively analyzed 22 patients who underwent parathyroidectomy for primary hyperparathyroidism (benign, 21; malignant, 1) from July 2018 to October 2019. In total, 27 specimens were examined. Approximately 1 mm3 of minced HPT as confirmed by frozen sections was suspended in 1 mL of normal saline and AST and LD levels were measured. The AST/LD ratios of other tissues (normal parathyroid tissue, thyroid gland, adipose tissue, and others; n = 94) were obtained from our previous report. The AST/LD ratio of benign HPT was consistently higher than that of other tissues (P < 0.001). The optimal cut-off value was 0.36 according to the receiver operating characteristic curve, with 100% sensitivity and specificity. The AST/LD ratio in malignant HPT was also markedly lower than that in benign HPT. This method might be a new adjunct for intraoperative differentiation of HPT with an accuracy and turnaround time comparable with those of frozen sections, minimal cost, and no need for dedicated pathological staff. Additionally, this method might increase the treatment success rate in settings with limited medical resources.