Background: The importance of parathyroid gland preservation in thyroid surgery has been well recognized; however, the rapid identification of the parathyroid gland, particularly the inferior parathyroid gland (IPG), remains challenging. This study aimed to evaluate the effectiveness of retrograde inferior parathyroid protection technique (RIPPT) based on thymus preservation.
Methods: A total of 236 patients were enrolled in this study between August 2019 and December 2020. RIPPT was employed to identify and protect the inferior parathyroid gland (IPG), and its identification rate and the anatomical variations were analyzed. The parathyroid hormone (PTH) and serum calcium levels were compared between patients who underwent IPG orthotopic retention and those who received IPG auto-transplantation, stratified by the anatomical type of the IPG.
Results: In total, the IPG identification rate was 97.88% (231/236), and the auto-transplantation rate was 74.46% (172/231). The anatomical relationship between IPG and thymus was observed in 77.97% of patients (184/236). Additionally, PTH levels were higher in patients with IPG orthotopic retention compared to those with IPG auto-transplantation both on postoperative day 1 (POD1) and at 6 months. PTH levels were also higher in patients with superior parathyroid gland (SPG) and IPG orthotopic retention compared to those who underwent both auto-transplantation procedures.
Conclusion: Retrograde inferior parathyroid protection technique (RIPPT) underscores the importance of protecting inferior parathyroid gland (IPG) in thyroid surgery and has been demonstrated to be effective in the rapid identification and functional preservation of IPG, based on short-term outcomes.
Clinical trial number: Not applicable.
Keywords: Inferior parathyroid gland; Papillary thyroid cancer; Retrograde inferior parathyroid protection technique; Thymus preservation; Thymus-related inferior parathyroid gland; Thyroid surgery.
© 2025. The Author(s).