Use of Fluorescence in parathyroid surgery

Background: Near-infrared autofluorescence (NIRAF) has recently been introduced for the identification of parathyroid glands (PGs), although its role in discriminating normal from abnormal PGs is debated. Indeed, the autofluorescence pattern of parathyroid adenoma is still under discussion. This is pilot study which aims to assess the autofluorescence pattern of parathyroid adenoma in patients affected by pHPT.

Methods: Between December 2021 and February 2022, 11 patients affected by pHPT underwent surgery with the aim of NIRAF for parathyroid adenoma. Parathyroid autofluorescence was assessed.

Results: Overall, 9 patients were affected by a single parathyroid adenoma, 1 patient by a double adenomas and 1 patient by a suspicious MEN 4 syndrome. 15 lesions have been removed: 14 parathyroid adenomas which showed a heterogeneous fluorescence pattern, and a schwannoma which showed a homogenous enhancement at NIR light. A well-defined “bright cap” was documented in 9 out of 15 specimens (64.3%).

Conclusion: Parathyroid adenomas show a heterogeneous autofluorescence pattern. Moreover, two-third of parathyroid adenomas showed an autofluorescent “bright cap”. These NIRAF features may be helpful in differentiating normal from abnormal parathyroid glands, especially in patients with a doubtful pre-operative localization. Further larger studies are required to confirm these findings.