Israel Medical Association Journal

Background: Direct aspiration from suspected pathological tissue and rapid parathyroid hormone analysis may offer a reliable, cost effective alternative to currently used “gold standard” tests.

Objectives: To validate the accuracy of intraoperative measurements of parathyroid hormone levels in parathyroid adenomas.

Methods: A prospective study included 22 patients diagnosed with primary hyperparathyroidism who underwent parathyroidectomy due to an adenoma or hyperplasia. Aspirations of tissues extracted from three adjacent areas (the pathological parathyroid, thyroid, and muscle tissues) were sent for rapid parathyroid hormone analysis. The assay values of these tissue aspirates were compared to the results of the pathology report based on frozen section analysis and the final pathology report.

Results: All assay results were significantly higher for parathyroid tissue 16,800 to 1,097,986 pmol/L (median 26,600), than for either thyroid 1.7 to 415 pmol/L (median 6.5), P < 0.001, or muscle tissue 1.1 to 1230 pmol/L, (median 11.3), P < 0.001. All tissues showing high parathyroid assay values were also verified by pathology examinations: 7 had adenomas and 15 had a differential diagnosis of adenoma or hyperplasia. The frozen section identified all but one (false negative). Rapid intraoperative parathyroid levels > 1500 predicted parathyroid tissue with a 99% level of confidence, while levels between 1000 and 1500 predicted it with 95% confidence. The intraoperative parathyroid hormone assay showed > 70% decrease in 15/21 cases.

Conclusions: Rapid intraoperative parathyroid hormone analysis is a reliable and precise technique, equally accurate for frozen section analysis in predicting with high certainty intraoperative parathyroid tissue.

Background: Four-dimensional parathyroid computed tomography (4DCT) is a relatively new parathyroid imaging technique that provides functional and highly detailed anatomic information about parathyroid tumors.

Objective: To assess the accuracy of 4DCT for the preoperative localization of parathyroid adenomas (PTAs) in patients with biochemically confirmed primary hyperparathyroidism (PHPT) and a history of failed surgery or unsuccessful localization using ^99mTc-sestamibi scanning and ultrasonography.

Methods: Between January 2013 and January 2015, 55 patients with PHPT underwent 4DCT at Hillel Yaffe Medical Center, Hadera, Israel. An initial unenhanced scan was followed by an IV contrast injection of nonionic contrast material (120 ml of at 4 ml/s). Scanning was repeated 25, 60, and 90 seconds after the initiation of IV contrast administration. An experienced radiologist blinded to the earlier imaging results reviewed the 4DCT for the presence and location (quadrant) of the suspected PTAs. At the time of the study, 28 patients had undergone surgical exploration following 4DCT and we compared their scans with the surgical findings.

Results: 4DCT accurately localized 96% (27/28) of abnormal glands, all of which were hypervascular and showed characteristic rapid enhancement on 4DCT that could be distinguished from Level II lymph nodes. Surgery found hypovascular cystic PTA in one patient who produced a negative 4DCT scan. All patients had solitary PTAs. The scan at 90 seconds provided no additional information and was abandoned during the study.

Conclusions: 4DCT accurately localized hypervascular parathyroid lesions and distinguished them from other tissues. A three-phase scanning protocol may suffice.

Background: Primary hyperparathyroidism in elderly patients is usually associated with additional co-morbidity that increases operative risk, and thus many geriatric patients are denied the benefit of surgery for a single parathyroid adenoma.

Objectives:  To evaluate the safety and efficacy of accurate single photon emission computed tomography sestamibi scintigraphy, enabling precise localization of a single adenoma, in the geriatric population

Methods: Twenty-two patients aged 70 years and over with biochemically proven PHPT[1] and with a single parathyroid adenoma identified by localization studies (sestamibi SPECT[2] scan and ultrasonography) underwent 23 operations over 29 months (out of a total of 140 patients operated upon during the same period). Immediate preoperative sestamibi scintigraphy and marking of focal adenoma uptake followed by intraoperative hand-held gamma probe were used for the removal of the parathyroid adenoma by unilateral minimal access surgery. Associated major co-morbid conditions and pre- and postoperative calcium, phosphorus and parathormone levels were recorded. Indications for surgery were listed and operative and postoperative complications were noted. The patients were followed for a mean period of 17.7 months using the same parameters.

Results: The 22 patients with PHPT had a mean age of 76.3 ± 5.9 years (range 70–88 years)  and a female to male ratio of 13:9. Associated co-morbidity included ischemic heart disease (n=15), hypertension (n=22), non-insulin-dependent diabetes mellitus (n=9), chronic obstructive pulmonary disease (n=3), and previous neck surgery (n=3). Mean preoperative serum calcium, phosphorous and PTH[3] were 11.7 ± 1.3 mg/dl, 2.5 ± 0.5 mg/dl and 160.9 ± 75.4 pg/ml respectively. In 20 of the 22 patients, surgery was successful in curing PHPT (91%). One patient had persistent hypercalcemia due to a missed adenoma, and repeat operation (by focused minimal access surgery) was successfully performed 2 weeks later. There were no complications and no morbidity postoperatively. Mean postoperative serum calcium, phosphorous and PTH were 9.6 ± 1.2 mg/dl, 3.0 ± 0.5 mg/dl and 35.2 ± 24 pg/ml respectively. In all patients, serum calcium levels remained normal (9.7 ± 1.3 mg/ml) after long-term follow-up (mean 17.7 ± 9.6 months).

Conclusions: Minimally invasive, radio-guided focused parathyroidectomy for a single adenoma is a safe and effective method to cure hyperparathyroidism in the elderly. Success of surgery is directly related to the surgeon's experience and to the precise localization marking provided by sestamibi scintigraphic SPECT localization and concurrent sonographic findings.