Endoscopic detection of near-infrared autofluorescence in the parathyroid glands: a case report of two patients.

INTRODUCTION AND

IMPORTANCE

Preservation of the parathyroid glands during thyroid surgery is crucial to prevent postoperative hypocalcemia. Parathyroid glands exhibit intrinsic autofluorescence with an emission peak around 820 nm, and near-infrared imaging has been applied for their intraoperative identification. However, its feasibility in endoscopic thyroid surgery remains unclear, particularly when using a small-diameter endoscope. Here, we report two cases in which parathyroid autofluorescence was successfully visualized during endoscopic surgery using a 5-mm endoscope.

CASE PRESENTATION: The first patient was a 75-year-old woman with breast cancer who was referred to us with a right thyroid nodule detected on preoperative positron emission tomography/computed tomography. Fine-needle aspiration cytology suggested papillary carcinoma, and as the nodule gradually enlarged, we performed a right thyroid lobectomy after 7 years using video-assisted neck surgery (VANS) with a 5-mm endoscope. A parathyroid gland on the posterior thyroid surface showed homogeneous and strong autofluorescence. The second patient was a 53-year-old woman with primary hyperparathyroidism who presented with hypercalcemia and elevated intact parathormone levels. We performed a right parathyroidectomy using VANS with the same endoscope. A parathyroid tumor showing heterogeneous and relatively weak autofluorescence was identified on the posterior aspect of the right thyroid lobe.

CLINICAL DISCUSSION: In both cases, near-infrared imaging revealed parathyroid autofluorescence during VANS. Adequate display settings, including enhanced brightness and contrast, appear to be important for clear visualization.

CONCLUSION

Parathyroid autofluorescence can be visualized even during endoscopic thyroid surgery with a 5-mm endoscope and may contribute to safer procedures.