Aim: Iatrogenic damage to the recurrent laringeal nerve is the most feared complication in thyroid surgery and the main cause for vocal cord palsy. Prevention of such a lesion is based upon the thorough search for the nerve along its anatomic pathway. In the present study the Authors discuss an important anatomic variation: non-recurrent inferior laryngeal nerve, emphasizing the aspects of surgical anatomy, on the basis of their own experience in neck surgery.
Materials and methods: The study takes into conideration 301 surgical interventions on the thyroid gland, in 268 women and 33 men; consisting in 256 total thyroidectomies and 45 loboisthmectomies, as follows: 186 for nodular goiter, 48 for follicular nodule, 34 for papillifer carcinoma, 33 for toxic goiter. The identification and exposure of inferior laryngeal nerve was performed according to the principles and technique by Lahey.
Results: The overall prevalence of non recurrent inferior laryngeal nerve was equal to 0.33% (1/301 operations). The anomaly is prevailing on the right side, being due by an anomalous reabsorption of the IV ventral arch. This is the cause of the formation of a subclavian artery that is responsible for dysphagia lusoria.
Conclusions: The rationale for the preservation of recurrent nerve is its systematic identification and exposure along all its course from its laryngeal entry. Diagnosis of non recurrent inferior laryngeal nerve is exclusively intra-operative. The anomaly is clinically asymptomatic and its suspicion can be posed in case of vascular anomalies or dysphagia. In such a circumstance the golden diagnostic tool is the angio Tc-RMN, while both the EGDS and baritate esophagous can be of some diagnostic help.