This Multicenter, Randomized Controlled Trial evaluates the clinical impact of parathyroid autofluorescence visualization using near infrared light (NIR) during total thyroidectomy (TT). It compares patients who undergo TT associated or not with lymph node dissection (LND) with NIR vs without NIR use during surgery.

Total thyroidectomy (TT) is responsible for postoperative hypocalcemia in 20-30% of patients, which is definitive in 1-4% of operated patients (1). This complication is mainly due to surgery-induced parathyroid dysfunction, which could be improved by a better intraoperative identification of the parathyroids. Intraoperative parathyroid auto-fluorescence visualization (without any dye injection) using near infrared light (NIR) is an emerging technique, which allows correct identification of normal parathyroids in almost all cases (2), but the clinical impact of NIR is unknown.

The aim of this prospective, comparative randomized study, is to compare 2 groups of patients: patients operated with NIR (NIR+) vs patients operated without NIR (NIR-).

The main objective of this study is to assess the impact of intraoperative use of NIR camera on postoperative hypocalcemia. Secondary objectives are to assess the impact of NIR on the visualization, autotransplantation and inadvertent resection rates during TT.

Inclusion Criteria:

• All patients eligible for one-stage total thyroidectomy, associated or not to lymph node dissection (TT +/- LND).

Exclusion Criteria:

• Combined parathyroid and thyroid disease (including patients with enlarged parathyroids incidentally found during surgery and resected)