Rapid Parathyroid Hormone Assay Research Articles

Investigating the effectiveness of intraoperative rapid parathyroid hormone assay in parathyroidectomy surgery in patients with secondary hyperparathyroidism

IntroductionThe use of Rapid Intraoperative parathyroid hormone (Io-PTH) assay during surgery in the management of parathyroid tissue in cases of primary hyperparathyroidism has been proven to be effective, while its utilization in secondary hyperparathyroidism (SHPT) has been rarely reported. In the present study, we aim to demonstrate the application of rapid Io-PTH assay in patients with SHPT following chronic kidney disease undergoing parathyroidectomy surgery.MethodIn this prospective study, five blood samples were taken from patients undergoing parathyroidectomy and upper thymectomy. Among the samples, two were pre-excision, including prior to the first incision, after exploration, and before parathyroids resection. Two additional samples were taken 10 and 20 min after the excision of the parathyroid glands. Another sample was collected twenty-four hours after the operation. Serum Calcium levels and PTH levels were evaluated and analyzed.ResultsWe successfully managed SHPT in all 36 patients in our study. The patients included 24 males (66.7%) with a mean age of 49.97 ± 14.92. The mean PTH decreased significantly at 10 min, 20 min, one day, and six months after surgery (P < 0.001). The highest reduction occurred 10 min after removal of the parathyroid glands so the mean PTH compared to time zero was reduced from 1737 to 439, and in 100% of cases, more than 50% reduction was seen in PTH.ConclusionA 60% or more reduction in PTH Rapid at 10 min after parathyroidectomy has an accuracy of 94.4% and a positive predictive value of 100%. Thus, if the PTH level does not decrease by more than 60% at 10 min or more than 80% at 20 min, tissue exploration is continued with the aim of finding the ectopic parathyroid gland.

A RARE CASE OF MAXILLARY BROWN TUMOUR AS PRIMARY PRESENTATION OF THE PARATHYROID CARCINOMA.

Background: Brown tumours are expansile osteolytic lesions of bone, occurring in Hyperparathyroidism. Brown tumours occur most commonly in ribs, clavicle, long bones and pelvis and are uncommon in other facial bones except mandible. Other facial bones are rarely affected. Brown tumors are due to the direct effect of the parathyroid hormone. Brown tumors occur more with primary hyperparathyroidism than secondary. However, they are reported more in secondary hyperparathyroidism. In primary hyperparathyroidism, a parathyroid adenoma is a cause in 81% while other causes include hyperplasia in 15% and parathyroid carcinoma only in 4%. We present a case report of maxillary Brown tumor due to parathyroid carcinoma in an elderly male patient. Case Report: A 67-year-old male presented with right maxillary swelling increasing in size for the last few months associated with ipsilateral nasal block and right eye epiphora. The contrast CT scan of paranasal sinuses and neck revealed a large expansile right maxillary tumor aggressively eroding maxillary wall with extension into the orbital oor, ethmoid, sphenoid sinuses, nasal cavity, and oral cavity with the erosion of hard palate and soft tissue extension to subcutaneous Plane. A three cm sized soft tissue density lesion was also noted posterior to the right thyroid lobe in CT sections of the neck. Blood prole was normal except extremely high serum parathormone and calcium as well as mildly elevated serum creatinine (S. PTH 3437 pg./ml. S. Ca. 19 mg%. S. Creatinine 1.77mg%.) Ultrasonography of the abdomen also revealed calcication in the renal medulla. Right lower parathyroidectomy was done with the frozen section as well as the Intraoperative Rapid PTH assay. The PTH level was reduced by 90 percent of the original value. The nal histopathology was suggestive of parathyroid carcinoma. Summary: The patient was under regular surveillance, as the maxillary tumor was under remittance after the resection of parathyroid carcinoma. Parathyroid carcinoma is a very rare tumor and involvement of maxillary bone due to primary hyperparathyroidism due to parathyroid carcinoma is also uncommon.

Evaluation of the diagnostic utility of the aminotransferase/lactate dehydrogenase ratio for the suspension of tissue specimens during thyroid surgery for the identification of parathyroid tissue.

Identification of the parathyroid glands during surgery is crucial for preventing postoperative hypoparathyroidism. Kikumori et al. reported that the aspartate aminotransferase (AST)/lactate dehydrogenase (LDH) ratio for the saline suspension of a suspicious tissue can differentiate parathyroid tissue from other tissues. The aim of this study was to evaluate the utility of this method and investigate the appropriate time for measurement. We obtained 465 tissue specimens during thyroidectomy of 102 patients with papillary thyroid carcinoma (PTC), and 422 specimens (129 parathyroid, 92 PTC, and 201 other tissues) with measurable AST and LDH were analyzed. Small pieces of the tissues were immersed in saline and sent for measurement of AST and LDH. The assay was performed immediately after thyroidectomy for 245 specimens (the same-day group) and during the next morning for the remaining 177 specimens (the next-day group). The accuracy of diagnosing parathyroid tissue was significantly better in the same-day group than in the next-day group. A cut-off value of 0.18 gave the best diagnostic precision, with an area under the receiver operating characteristic curve of 0.95 and 88.7% sensitivity and specificity in the same-day group. When the cut-off value was set to 0.20, the specificity for excluding carcinomatous tissues was 100%. When measured on the day of the surgery, the AST/LDH ratio for the saline suspension of the surgical specimens is useful for discriminating parathyroid tissues from other tissues. This method can be utilized at most hospitals where intraoperative frozen sections or rapid parathyroid hormone assays are not available.

Focused Parathyroidectomy Using Accurate Preoperative Imaging and Intraoperative PTH: Tertiary Care Experience.

Introduction:The cure rate after focused parathyroidectomy (FP) is dependent upon two critical adjuncts- concordant preoperative imaging and intraoperative parathyroid hormone (PTH), a technique which can reliably determine whether any other hyperfunctioning gland or glands are still present after resection of the lesion shown by imaging. We wanted to see the cure rate of FP by using these two adjuncts. We also sought to discern whether utilizing the central lab rapid PTH assay will lead to wider acceptance of this FP with intraoperative PTH in resource-constrained countries. This analysis was also undertaken to find out cost-effective way of doing intraoperative PTH by minimizing the samples for intraoperative PTH study.Result:Data were collected on 83 patients with sporadic primary hyperparathyroidism (PHPT) who underwent parathyroidectomy in two tertiary centers between '2009 and 2017'. A total of 75 patients had concordant imaging, while seven had discordant imaging. The sensitivity and specificity of intraoperative PTH in FP was 100%. All the 78 patients who had fall in intraoperative PTH (50%) at 10 min also had fall of more than 50% at 5 min except one patient (98.7%).Conclusion:We strongly advocate routine use of intraoperative PTH in all patients undergoing minimally invasive parathyroidectomy, as this adjunct offers maximum safety for the patient and confidence for the surgeon. Cost can be minimized by utilizing the central laboratory and reducing the number of samples.

Intraoperative measurement of parathyroid hormone: A Copernican revolution in the surgical treatment of hyperparathyroidism

Intraoperative parathyroid hormone (PTH) monitoring in the setting of the operating room represents a valuable example of the rationale use of the laboratory diagnostic in a patient-oriented approach. Rapid intraoperative PTH (ioPTH) assay is a valid tool for an accurate evaluation of the success of parathyroid surgery. The reliability of the user-friendly portable systems as well as the collaboration between operators and surgical staff allow the one-site monitoring of the ioPTH decrements on the course of the surgical management of hyperparathyroidism.The rapid answer provided by an effective decrement of PTH during parathyroidectomy contributes dramatically to the efficacy of parathyroid surgery and the reduction of the number of re-operations. Therefore the dose of ioPTH is a valid and reliable support for the success of the intervention of parathyroidectomy at controlled costs.

Minimally invasive parathyroidectomy without using intraoperative parathyroid hormone monitoring or gamma probe.

Minimal invasive parathyroidectomy (MIP) is a common surgical technique for the treatment of primary hyperparathyroidism (PHPT) and is usually done in conjunction with positive imaging techniques. We aimed to assess the results of this technique, performed without the use of intraoperative tests, in cases with PHPT caused by a single parathyroid adenoma. The data for patients who were diagnosed with PHPT were assessed retrospectively. Only those who had undergone a parathyroid adenoma localization study with ultrasonography (US) and parathyroid scintigraphy (PS) before the surgery, along with those patients for whom the MIP technique was routinely performed with frozen pathology, were included. The study group was made up of 65 patients who had undergone the MIP technique. The mean age of the patients was 56±14 (20-81), with most being females [M/F: 19 (29.2%)/46 (70.8%)]. The mean calcium values before the operation were 11.24±1.26 mg/dL (8-15.5) (normal range: 8.4-10.2), and the parathyroid hormone (PTH) values were 388 pg/mL (249-707.75). These same values, measured 24 hours after the operation, were determined as 9.04±1.04 mg/dL (6.8-13.9) and 27 pg/mL (6-86), respectively. The follow-up period for the patients was an average of 26.6±9.4 (3-76) months, and only 3 (4.6%) cases of persistent hyperparathyroidism were detected within this period. Our success rate with MIP in PHPT cases was determined to be 95.4%; therefore, this technique may be applied with a high success rate without any assistance from intraoperative tests, such as rapid serum PTH (rPTH) assays or gamma probes, in the presence of localization results of PS and US.

Real-Time Super Selective Venous Sampling in Remedial Parathyroid Surgery

Remedial cervical exploration for persistent or recurrent primary hyperparathyroidism can be technically difficult, but is expedited by accurate preoperative localization. We investigated the use of real-time super selective venous sampling (sSVS) in the setting of negative noninvasive imaging modalities. We performed a retrospective analysis of a prospective database incorporating real-time sSVS in a tertiary academic medical center. Between September 2001 and April 2014, 3,643 patients were referred for surgical treatment of primary hyperparathyroidism. Of these, 31 represented remedial patients who had undergone one (n=28) or more (n=3) earlier cervical explorations and had noninformative, noninvasive preoperative localization studies. We extended the use of the rapid parathyroid hormone assay in the interventional radiology suite, generating near real-time data facilitating onsite venous localization by a dedicated interventional radiologist. The predictive value of real-time sSVS localization was investigated. Overall, sSVS correctly predicted the localization of the affected gland in 89% of cases. Of 31 patients who underwent sSVS, a significant rapid parathyroid hormone gradient was identified in 28 (90%), localizing specific venous drainage of a culprit gland. All patients underwent subsequent surgery and were biochemically cured, with the exception of one who had metastatic parathyroid carcinoma. Three patients with negative sSVS were also explored and cured. Preoperative parathyroid localization is of paramount importance in remedial cervical explorations. Real-time sSVS is a sensitive localization technique for patients with persistent or recurrent primary hyperparathyroidism, when traditional noninvasive imaging studies fail. These results validate the utility and benefit of real-time sSVS in guiding remedial parathyroid surgery.

Intraoperative parathyroid hormone assay during focused parathyroidectomy: the importance of 20 minutes measurement

BackgroundParathyroid hormone (PTH) monitoring during the surgical procedure can confirm the removal of all hyperfunctioning parathyroid tissue, as the half-life of PTH is approximately 5 min. The commonly applied Irvin criterion is reported to correctly predict post-operative calcium levels in 96-98% of patients. However, the PTH baseline reference concentration is markedly influenced by surgical manipulations during preparation of the affected glands, interindividual variability of the PTH half-life and modifications in the physiological state of the patient during surgery. The aim of this study was to evaluate the possible impact of the measurement of intraoperative PTH 20 minutes after surgery.MethodsBetween 2003 and 2012, 188 patients underwent a focused parathyroidectomy associated to rapid intraoperative PTH assay monitoring. Blood samples were collected: 1) at pre-incision time, 2) at 10 min after gland excision and 3) at 20 min after excision, if a sufficient reduction of PTH value was not observed. On the bases of the Irvin criterion, an intra-operative PTH drop>50% from the highest either pre-incision or pre-excision level after parathyroid excision was considered a surgical success.ResultsA >50% decrease of PTH after gland excision compared to the highest pre-excision value occurred in 156/188 patients (83%) within 10 min and in further 12/188 after 20 minutes (6.4%). In the remaining 20 patients (10.6%) values of PTH remained substantially unchanged or decreased less than 50% and for this reason bilateral neck exploration was performed. An additional pathologic parathyroid was removed in 9 cases, a third in one. In the other 10 cases further neck exploration by a standard cervical approach was negative and in four of these persistent postoperative hypercalcemia was demonstrated. The overall operative success was 97.3%. Intraoperative PTH monitoring was accurate in predicting operative success or failure in 96.3% of patients.ConclusionsThe 20 minutes PTH measurement appears very useful, avoiding unnecessary bilateral exploration and the related risk of complications with only a slight increase of the duration of surgery and of the costs. PTH values decreasing appeared to be influenced by surgical manipulations during minimally invasive parathyroidectomy.

Minimally Invasive Radioguided Parathyroidectomy

The surgical management of hyperparathyroidism has evolved over the last 20 years, transitioning from routine bilateral neck exploration to, frequently, a minimally invasive approach. Adjuncts which have made this transition possible include advancements in imaging techniques which allow the pre-operative localization of adenomatous glands, the rapid parathyroid hormone assay and the use of 99-m technetium sestamibi injections the day of surgery to allow for gamma probe detection of abnormal glands. The gamma probe can help with gland localization, which can be particularly useful in a re-operative field or with glands in ectopic locations. It is also helpful in confirming that excised tissue is abnormal parathyroid tissue, alleviating the need for frozen sections during surgery. In this chapter we discuss and review radioguided minimally invasive parathyroidectomy.

Evaluation of the ‘putative’ role of intraoperative intact parathyroid hormone assay during parathyroidectomy for secondary hyperparathyroidism. A retrospective study on 35 consecutive patients

In the surgical treatment of secondary hyperparathyroidism (2HPT) of chronic kidney disease (CKD), a parathyroidectomy (PTx) of 4 glands can only be presumed as 'total', and indications for autoimplantation are complex. Intraoperative rapid parathyroid hormone assay could be useful to predict a radical resection. We evaluated iPTH levels 20 min and 24 h after a 4-gland PTx in 35 patients to determine the predictive value of intraoperative iPTH assay. We analysed retrospectively 35 patients affected by 2HPT of CKD, 13 undergoing total parathyroidectomy (TP) and 22 TP + autoimplantation (TPai), after removing 4 glands in 33 cases and 5 glands in 2. Intact PTH assays were acquired after 40 min before induction of anaesthesia, after removing both ipselateral glands, at 20 min after surgery and on postoperative day 1. 20 min after 4-gland PTx, a decrease of iPTH levels >80 % of the preoperative value was observed in 27 of 35 cases (77.1 %) and <80 % in 8 of 35 cases (22.8 %). In 6 of these 8 patients, iPTH levels were within the normal range 24 h after surgery. Although the intraoperative iPTH assays are of interest in the treatment of 2HPT, the predictive value of this method is not entirely satisfactory. In fact, a 4-gland PTx ensures euparathyroidism in most cases, even when intraoperative iPTH assays are not trustworthy; however, intraoperative iPTH assay, although not a perfect 'tool', is a proved aid for the surgeon in making his decision.

A 10-Year Experience in Intraoperative Parathyroid Hormone Measurements for Primary Hyperparathyroidism: A Prospective Study of 91 Previous Unexplored Patients

Introduction. Primary hyperparathyroidism (PHP) is characteristically determined by high levels of calcium and high or inappropriate levels of parathyroid hormone (PTH). Technological advances have dramatically changed the surgical technique over the years once intraoperative parathyroid hormone (IOPTH) assay had allowed for focused approaches. Objective. To evaluate our 10-year experience in employing a rapid intraoperative PTH assay for PHP. Methods. A prospective cohort of 91 PHP-operated patients in a tertiary institution in São Paulo, Brazil, from June 2000 to April 2011. Results. We had 85 (93.4%) successful parathyroidectomies, 6 (6.6%) failed parathyroidectomies in 91 previous unexplored patients, and 5 (100%) successful remedial surgeries. The IOPTH was true-positive in 88.5%, true-negative in 7.3%, false-positive in 2.1%, and false-negative in 2.1% of the procedures. IOPTH was able to obviate additional exploration or to ask for additional exploration in 92 (95.8%) procedures. Conclusion. The IOPTH revealed to be an important technological adjunct in the current parathyroid surgery for PHP.

Intraoperative parathyroid hormone as an indicator for parathyroid gland preservation in thyroid surgery

Intra-operative parathyroid hormone (PTH) levels have successfully been used to assess surgical ablation of parathyroid adenomas, the use of this same test to predict preservation of viable gland has not been widely used. to test the sensitivity and specificity of intraoperative rapid PTH assay test in predicting permanent postoperative hypoparathyroidism, and applicability to guide the search for inadvertently removed parathyroid glands for possible auto transplantation. 52 patients undergoing total thyroidectomy for non-malignant thyroid diseases were included. Intraoperative rapid PTH assay test was performed. If levels were reduced, or less than 3 parathyroid glands were detected, removed thyroid gland was examined for unintentionally removed parathyroid tissue for possible auto transplantation. There was a strong correlation between intraoperative rapid PTH assays and those taken 24 hours after surgery, 16 out of 52 patients had reduction of the PTH intraoperatively to levels below 25 pg/ml, of them, 11 patients (who had values between 15-24 pg/ml) recovered to normal PTH levels within 4 weeks, while the 5 patients with intraoperative PTH levels below 15 pg/ml failed to regain normal PTH levels up to 12 weeks postoperatively, even in those patients where parathyroid tissue was auto transplantated. The 4 patients who had parathyroid tissue reimplanted intraoperatively restored some of their parathyroid function as indicated by relative rise of their PTH levels, but did not reach even the low normal levels. (ROC) curve for prediction of early hypoparathyroidism using intraoperative rapid PTH assay was statistically highly significant with optimal cutoff value for predicting early hypocalcaemia level <27 pg/ml, (sensitivity 100%, specificity 68.2%). (ROC) curves for predicting permanent hypoparathyroidism using intraoperative rapid PTH assay or standard PTH assay taken 24 hours after surgery were statistically significant with optimal cutoff value PTH level <12 pg/ml on the intraoperative PTH curve or <15 pg/ml on the postoperative PTH curve (sensitivity 100%, specificity 100%). Intraoperative PTH assay may allow intraoperative monitoring of parathyroid function, predicting postoperative outcomes, may identify patients at risk of developing postoperative hypoparathyroidism, guiding surgeons to re-examine removed specimens for inadvertently removed parathyroid tissue with possible auto transplantation, or more practically a guide to early replacement therapy to prevent hypocalcaemia, leading to safe and early hospital discharge. Limitations in our study to be reconsidered in further studies, are relative small sample size, inability for randomisation, and the variable values reported for the cut off value of PTH causing hypocalcaemic symptoms needing intervention.

Evolution of Endocrine Surgery in India

Evolution of Endocrine Surgery in India

Secondary and Tertiary Hyperparathyroidism: The Utility of ioPTH Monitoring

The aim of the present study was to examine the utility of intraoperative parathyroid hormone (ioPTH) monitoring in patients with secondary (2) and tertiary (3) hyperparathyroidism (HPT). We identified 105 patients with 2HPT (n = 33) and 3HPT (n = 72) who underwent ioPTH monitoring during parathyroidectomy. Data are reported as mean +/- SEM. The 2HPT patients underwent 17 subtotal, 10 total, and 6 re-exploratory parathyroidectomies, whereas the 3HPT patients underwent 54 subtotal, 15 limited, and 3 re-exploratory parathyroidectomies. The percent decrease from the baseline ioPTH level at 5, 10, and 15 min after parathyroid resection, respectively, were 72% +/- 3%, 76% +/- 3%, and 76% +/- 3% in patients with 2HPT, and 52% +/- 6%, 60% +/- 4%, and 69% +/- 4% in patients with 3HPT. IoPTH levels failed to drop >50% from baseline in 5 patients (2HPT: n = 2, 3HPT: n = 3) who were normocalcemic at last follow-up. IoPTH did not alter the surgical approach in any 2HPT patients, but did alter management in 25% of 3HPT patients (15 limited resections and 3 supernumerary glands). Normocalcemia was achieved in 97% of 2HPT patients and 99% of 3HPT patients; 2 patients developed recurrent disease. Intraoperative PTH levels fell by >50% in nearly 95% of patients with 2HPT and 3HPT, and the PTH level reliably predicted postoperative cure. Although the use of ioPTH did not alter surgical management in any patient with 2HPT, this rapid PTH assay affected the surgical care of a quarter of the patients with 3HPT, and it may prove to be a useful adjunct in this group of patients.

Surgery of parathyroid

Surgery of parathyroid revolves around the management of hyperparathyroidism (HPT). In most cases, occurrence is sporadic rather than familial, and 80-85% of cases of sporadic primary HPT are caused by a solitary parathyroid adenoma. The diagnosis is made by hypercalcaemia with an inappropriately elevated parathyroid hormone (PTH) level and a 24-hour urine calcium excretion level that is normal or high. Improved assay for PTH has led to earlier detection of HPT and has been responsible for the apparent increase in the prevalence of the disorder. An improvement in preoperative localisation studies as well as the development of a rapid intraoperative PTH assay has changed the approach to parathyroid surgery in the last two decades. This article provides a brief overview of management of primary HPT.

Spurious decline in intraoperative parathyroid hormone: false positives in parathyroid surgery

Objectives The aims of this study were to (1) describe a false-positive result using a highly sensitive intraoperative parathyroid hormone (PTH) assay in an adult patient with primary hyperparathyroidism and (2) discuss the potential pitfalls of revision parathyroid surgery and the implication of various localization techniques described in the literature. Methods A case report is described from a tertiary care university hospital. A literature review detailing diagnostic tools used to improve outcomes in parathyroid surgery is presented. The potential inaccuracies of intraoperative PTH assays are discussed. Results We present a 71-year-old woman with primary hyperparathyroidism who was referred to our institution for revision surgery. The patient had preoperative sestamibi imaging that localized a right inferior parathyroid lesion. Intraoperatively, a specimen consistent with parathyroid tissue was removed and sent for frozen section. The intraoperative PTH levels were noted to decrease from 154 pg/mL (preincision) to 28 pg/mL (20 minutes postexcision). The frozen section results were consistent with a lymph node. This stimulated a 4-gland exploration, which confirmed normal left superior and inferior parathyroid glands. A 1.5-cm right retroesophageal parathyroid was subsequently discovered and excised. Final intraoperative PTH levels were 20 pg/mL. Conclusion Rapid PTH assays have become the mainstay of parathyroid surgery at many institutions; however, despite their accuracy, false-positive results are known to occur. We present a case of an inaccurate decline in intraoperative PTH and use this case report as a means to highlight some potential pitfalls of the test.

Utility of intraoperative bilateral internal jugular venous sampling with rapid parathyroid hormone testing in guiding patients with a negative sestamibi scan for minimally invasive parathyroidectomy—a randomized controlled trial

The purpose of this study was to determine the utility of bilateral internal jugular venous sampling with rapid parathyroid hormone assay (BIJV-IOPTH) in comparison to endocrine surgeon-performed ultrasonography of the neck as an alternative localizing modality in guiding patients with primary hyperparathyroidism (pHPT) and negative sestamibi scans for minimally invasive parathyroidectomy (MIP). Seventy eight consenting patients with a negative subtraction sestamibi scan planned for parathyroidectomy underwent additional ultrasound parathyroid imaging and were randomized to undergo surgery without vs. with additional BIJV-IOPTH; n = 39 in each group. The patients with a positive alternative imaging test were qualified for video-assisted MIP, whereas the others underwent open neck explorations. The primary outcome measure was the number of patients with true-positive results of alternative imaging tests. Of the 78 patients, 50 (64%) had a single adenoma, eight (10.3%) had double adenomas, and 20 (25.7%) demonstrated four-gland hyperplasia. Ultrasonography alone vs. combined with BIJV-IOPTH was true positive in detecting a solitary parathyroid adenoma in 8/24 (33.3%) vs. 17/26 (65.4%) patients, respectively (p = 0.023). Curative video-assisted MIP was successfully performed in all the patients with true-positive results. The remaining individuals were cured by more extensive open neck explorations (unilateral-4/39 vs. 4/39, respectively; p = 1.0 or bilateral-27/39 vs. 18/39, respectively; p = 0.039). Most patients with pHPT and a negative subtraction sestamibi scan (64%) have a single adenoma. BIJV-IOPTH as an addition to a surgeon-performed ultrasound of the neck allows for more accurate guiding for MIP in patients with a solitary parathyroid adenoma and negative subtraction sestamibi scans.

Remedial Operation for Primary Hyperparathyroidism

Remedial surgery for patients with persistent or recurrent primary hyperparathyroidism (1 degrees HPT) remains a significant challenge. Cervical reexploration is technically difficult; reoperative neck anatomy is distorted by fibrosis and, as a result, remedial 1 degrees HPT patients carry an increased risk of injury to the recurrent (RLN) and superior laryngeal nerve(s) as well as to normal residual parathyroid tissue. Causative hyperfunctioning parathyroid tissue is also more frequently ectopic in the remedial setting and can thus be difficult to localize. This report assimilates the current data underlying preoperative, intraoperative and postoperative remedial 1 degrees HPT management and presents an evidence-based algorithm for the management of remedial parathyroid disease. Recommendations are graded according to the quality of supporting data using the system initially developed by Sackett (Chest 95:2S-4S, 1989) and subsequently modified by Heinrich et al. (Ann Surg 243:154-168, 2006). Recent advances in preoperative localization and intraoperative adjuncts have lead to substantial improvements in outcomes after remedial surgery. Preoperative localization techniques, including sestamibi scintigraphy (MIBI), high resolution ultrasound (US), US-guided fine needle aspiration (FNA) and selective venous sampling (SVS), coupled with intraoperative adjuncts such as the rapid parathyroid hormone (PTH) assay have lead to reoperative cure rates as high as 96 percent. Nonetheless, management of remedial 1 degrees HPT varies significantly between surgeons and no formal recommendations standardizing the care of these patients have been published. Despite the significant challenges associated with remedial surgery for 1 degrees HPT, excellent outcomes can be reproducibly achieved when proper pre-, intra-, and postoperative management is employed.

Chirurgie de l’hyperparathyroïdie primaire en 2008

In recent years, different minimally invasive techniques of parathyroidectomy have been described. The concept of these limited explorations is based on the fact that 85% of patients will have a single-gland disease. Minimally invasive techniques are targeted on one specific parathyroid gland and in most cases the exploration of other glands is not performed. These interventions are today possible for three main reasons: the available imaging techniques permit to localize the diseased gland, the use of rapid intraoperative PTH assay can confirm the successful extirpation, new instrumentation and miniaturized cameras have been adapted for this kind of surgery. Not all patients presenting with primary hyperparathyroidism are candidate for this surgery. Contraindications are mainly due to a large goiter, previous surgery in the parathyroid vicinity, suspicious multiglandular disease and equivocal preoperative localization studies. Currently 60% of patients with primary hyperparathyroidism can benefit of these techniques. Studies comparing conventional parathyroid surgery to minimally-invasive techniques have shown a diminution of postoperative pain and better cosmetic results with minimally-invasive techniques. If early results are similar to those obtained with conventional parathyroidectomies, it is still too soon to evaluate what will be the recurrence rate of these new techniques. One can expect that minimally invasive and conventional parathyroid surgery will probably turn out to be complementary in the near future.

Validation of a Rapid Parathyroid Hormone Assay and Intraoperative Measurement of Parathyroid Hormone in Dogs with Benign Naturally Occurring Primary Hyperparathyroidism

To (1) validate a rapid chemiluminescent parathyroid hormone (PTH) assay, (2) determine it's usefulness locating a parathyroid nodule(s), and (3) determine if >50% decrease in PTH corresponds with excision of autonomously functioning parathyroid tissue. Prospective cohort study. Dogs (n=12) with naturally occurring primary hyperparathyroidism and 25 healthy dogs. The assay was validated with linearity, precision, and intermethod comparison. Preoperative and postoperative systemic plasma PTH concentrations, measured from saphenous venous blood, were compared. Intraoperative local PTH concentrations were measured in right and left jugular venous blood before and after surgical excision of the grossly abnormal parathyroid gland(s). Within run and day-to-day precisions were acceptable (coefficient of variation <15%). Dilutional parallelism was used to demonstrate high correlation between measured and calculated PTH concentrations (R(2)=0.99). The assay methods had good correlation but numerical results of the rapid assay were usually lower than the immunoradiometric assay. Seven of 12 dogs had uniglandular disease and five had multiglandular disease. Systemic and local PTH concentrations decreased >50% in all the dogs after excision of the parathyroid gland(s). Mean preoperative systemic plasma PTH concentrations were significantly higher than mean postoperative systemic concentrations. Local PTH concentrations could not be used reliably to differentiate the side of the autonomously functioning gland(s). Hypercalcemia resolved postoperatively in all the dogs. This assay measures PTH in dogs. Rapid PTH measurement provided documentation of decreased PTH concentration after removal of autonomously functioning parathyroid tissue. Use of this assay allows documentation of a significant decrease in PTH concentration after excision of autonomously functioning parathyroid tissue.