Non-recurrent inferior laryngeal nerve: case report and review of the literature

Abstract

Total thyroidectomy is nowadays the operation of choice in the majority of endocrine surgery centers, whether the pathology is benign or malignant. To obtain good results, a thorough knowledge of local anatomy and a profound respect for hemostasis are necessary. Routine, at least visual, identification of the inferior laryngeal nerve (ILN) is considered gold standard and is strongly recommended. Surgeons are generally aware of the variations the nerve can have, especially on the right side. Although very rare, one such variation, with possible great impact on outcomes, is the non-recurrent route of the nerve. We present the case of a middle-aged woman with a multinodular goiter scheduled for elective surgery. During total thyroidectomy, on the right side, we were not able to find the inferior laryngeal nerve in its usual position, using the customary anatomical landmarks. Instead, we encountered it emerging directly from the right vagus nerve, at a rather right angle and entering the larynx as a unique non-bifurcating nerve. Thus, it could be spared from any injury and protected, although it could have been easily confounded with a vascular structure, given its transverse course.We think it is never overmuch to repeat that the routine identification and exposure of the inferior laryngeal nerve is a must for the thyroid surgeon in order to safely preserve its integrity.

Keywords: inferior laryngeal nerve; non-recurrent; total thyroidectomy.

Fig. 1

Total thyroidectomy for a multinodular goiter with the left lobe significantly bigger

Fig. 2

A transverse nervous structure emerging from the right vagus – non-recurrent inferior laryngeal nerve (ILN); the thyroid have been excised; CCA – common carotid artery; E – esophagus; TC – thyroid cartilage

Fig. 3

Aberrant right subclavian artery emerging from the aortic arch after the left subclavian (7)