Minimally invasive endoscopic-assisted parathyroidectomy for primary hyperparathyroidism C.-Y. Lo, W. F. Chan, J. M. Luk Division of Endocrine Surgery, Department of Surgery, The University of Hong Kong Medical Center, Queen Mary Hospital, Pokfulam Road, Hong Kong, China Received: 14 March 2003/Accepted: 4 July 2003/Online publication: 28 October 2003 Abstract Background: Minimally invasive surgery for primary hyperparathyroidism (pHPT) depends on both an ac- curate preoperative localization and the availability of intraoperative parathyroid hormone monitoring. Methods: Patients with sporadic pHPT and one une- quivocally enlarged parathyroid gland on preoperative imaging underwent endoscopic-assisted parathyroidec- tomy. Intraoperative rapid parathyroid hormone (quick PTH) monitoring was performed, and surgical success was confirmed when there was a >50% decrease in quick PTH level 10 min after excision as compared with the baseline level at induction. The surgical outcome and the use of preoperative localization, together with the role played by quick PTH assay in enhancing the op- erative success, were evaluated. Results: From 1999 to 2002, 66 of 107 patients (62%) were selected for this approach. The accuracy of 99m Tc- Sestamibi scintigraphy and ultrasonography was 97% and 70%, respectively. Conversion was required in four cases due to technical problems, and four additional patients failed to show a significant decline in quick PTH levels postexcision. Two patients underwent cer- vical exploration without the finding of any additional pathology, and another two patients had a delayed drop in quick PTH that was confirmed 30 min postexcision. All patients had a solitary adenoma and were cured of hypercalcemia during a median follow-up of 9 months. Conclusions: Minimally invasive endoscopic-assisted parathyroidectomy can be performed expeditiously in a select group of patients based on 99m Tc-Sestamibi scin- tigraphy. The use of quick PTH assay can ensure sur- gical success, but careful interpretation of the results is mandatory. Key words: Primary hyperparathyroidism — Mini- mally invasive surgery — Endoscopic-assisted para- thyroidectomy — Parathyroid gland — Adenoma Parathyroidectomy is generally recommended for pa- tients with a confirmed diagnosis of primary hyperpar- athyroidism (pHPT) [22]. Although conventional bilateral cervical exploration has been successful in treating this condition [26], the availability of a highly accurate preoperative imaging technique [3, 20] and the development of intraoperative parathyroid hormone (PTH) monitoring [13, 14] have led to the adoption of a more focused, minimally invasive approach to para- thyroidectomy for pHPT [12, 19, 21]. Since the first description of endoscopic parathyroi- dectomy in 1996 [5], numerous reports have described a variety of different techniques for minimally invasive parathyroidectomy (MIP) that use preoperative or intraoperative means of localization as well as intra- operative rapid PTH monitoring. The reliability of intraoperative quick PTH assay in confirming surgical success or predicting multiglandular disease has been confirmed in many studies [2, 4, 6, 9, 10, 12–14, 17, 27] although this technique is not without its potential pit- falls [8, 10, 15, 23, 24]. Because there are numerous methods for MIP, none of which has been accepted as the standard technique, these new approaches need to be evaluated carefully and compared objectively with the excellent results obtained when practitions rely solely on their surgical expertise. The present report summarizes our experience with the application of endoscopic-assisted MIP through a midline incision for selected patients with pHPT. We evaluated the surgical outcome and the role of preop- erative imaging in selecting patients eligible for this approach, as well as addressing some potential pitfalls of the intraoperative PTH assay in confirming surgical success. Correspondence to: C.-Y. Lo Surg Endosc (2003) 17: 1932–1936 DOI: 10.1007/s00464-003-9072-2 Ó Springer-Verlag New York Inc. 2003