Non-recurrent laryngeal nerve coexisting with ipsilateral recurrent nerve: personal experience and literature review

Non-recurrence and variations in ascending course of the recurrent laryngeal nerve (RLN) represent a risk factor for nerve injuries during thyroid surgery. Non-recurrent laryngeal nerve (NRLN) coexisting to recurrent nerve branch is a rare anatomic anomaly. It could be a cause of nerve injuries during thyroidectomy. A systematic intraoperative nerve identification may allow an effectiveness prevention of iatrogenic injuries.

We report one case of a young woman underwent to total thyroidectomy (TT) for papillary thyroid carcinoma (PTC) where we found a rare variation of the right inferior laryngeal nerve anatomy. We identified both right laryngeal nerve structures before completing thyroidectomy avoiding possible nerve damage. The postoperative course was without complications.

Iatrogenic injury of RLN is one of the most serious complication in thyroid surgery. Several risk factors favouring this complication were found as the presence of anatomic variations of the inferior laryngeal nerve. Identification of a normal caliber recurrent nerve can allow the surgeon to complete the thyroid excision; diversely, in case of a smaller caliber nerve in the usual recurrent course, a careful dissection should be continued to demonstrate a possible merger with ipsilateral non-recurrent nerve.

The aim of this paper is to report a rare case of NRLN associated to a smaller caliber branch of RNL. We emphasize that careful dissection and intimate knowledge of normal and anomaly anatomy allow for avoidance of nerve injury during surgery in the neck.