Proactive Exploration of Inferior Parathyroid Gland Using a Novel Meticulous Thyrothymic Ligament Dissection Technique

Introduction: The inferior parathyroid gland (IPTG) is widely distributed; effective techniques for its safe exploration and protection during thyroid surgery have not been documented. The thyrothymic ligament (TTL) is a connective tissue located between the thymic tongue and thyroid. This study aims to introduce a novel meticulous thyrothymic ligament dissection technique and assess its role in proactive exploration and situ preservation of IPTG.

Materials And Methods: 737 patients undergoing initial thyroid surgery between 2017 and 2021 in the Department of General Surgery of the First Affiliated Hospital of Nanjing Medical University were retrospectively recruited for this clinical study. In 391 of the recruited patients, the TTL was dissected, and the number and location of IPTG were recorded. Among them, 214 patients underwent total/near-total thyroidectomy (TT) plus central neck dissection (CND) were assigned to the observation group. The control group included 346 consecutive patients who underwent conventional TT plus CND. After 1:1 propensity score matching, each group contained 206 patients. The incidence of postoperative hypoparathyroidism was recorded.

Results: Among the 391 patients, 596 sides were dissected, out of which 436 sides (73.2%) had TTL, and approximately 90.1% of IPTG were located and identified. A statistically significant difference in incidence of temporary (27.7 vs. 49.0%, P < 0.001) and permanent hypoparathyroidism (0 vs. 8.2%, P = 0.047) was noted between the observation group and the control group.

Conclusion: The meticulous thyrothymic ligament dissection technique helps to protect IPTG in situ and reduce the incidence of postoperative hypoparathyroidism.