The use of superior parathyroid gland as an anatomical landmark in identifying recurrent laryngeal nerve during total thyroidectomy: a prospective single-surgeon study.

Purpose: This study was performed to determine the anatomical position of recurrent laryngeal nerve (RLN) relative to superior parathyroid gland (SPG) in a consecutive total thyroidectomy series.

Methods: A total of 421 patients (mean age, 45.6 years; female, 76.0%) who had total thyroidectomy accompanied with intraoperative exposure of RLN in relation to SPG were included in this prospective single-surgeon thyroidectomy series study. The relation of RLN to SPG was assessed based on the measurement of the natural distance between the RLN and SPG, which was categorized as 0-5 mm, 6-10 mm, and ≥11 mm.

Results: Most of the thyroidectomy indications (69.1%) were related to malignant disease including papillary carcinoma in 54.9% of cases. Overall, in 90.7% of patients RLN was identified within 5 mm of the SPG, and in 65.1% of cases, it was found within 1 mm of the SPG. The RLN was found between 6 and 10 mm from the SPG in 8.5% of cases, while it was at least 11 mm away from the SPG in 0.7% of cases.

Conclusion: In conclusion, this prospective single-surgeon thyroidectomy series study indicates the likelihood of localizing the RLN in close proximity to SPG during total thyroidectomy operations. Hence, the SPG can be used as a landmark to identify RLN, and as part of routine parathyroid-sparing thyroidectomy, it may represent a convenient complementary approach to minimize the risk of iatrogenic injury to RLN in patients with an intact SPG.