Identification of non-recurrent right inferior laryngeal nerve during thyroidectomy

The non-recurrent right inferior laryngeal nerve is a rare anatomical variant of the recurrent laryngeal nerve, almost always associated with an aberrant right subclavian artery (Arteria Lusoria). Its unusual course increases the risk of iatrogenic injury during thyroid and neck surgery. A 45-year-old woman underwent right hemithyroidectomy for a solitary thyroid nodule suggestive of a follicular tumor. The recurrent laryngeal nerve was not found in its expected tracheoesophageal location. Careful dissection of the vagus nerve revealed a non-recurrent branch arising near the thyroid superior pole and coursing horizontally to the larynx. The nerve was preserved, and surgery was completed uneventfully without intraoperative neuromonitoring. The non-recurrent right inferior laryngeal nerve lies higher and more anterior than the recurrent pathway strongly linked to Arteria Lusoria. Failure to recognize it may cause permanent vocal cord paralysis. Preoperative imaging may suggest its presence, but intraoperative identification through meticulous vagus dissection remains essential for safe surgery.