The Preoperative Diagnosis of an NRILN could Reduce the Risk of Vocal Cord Paralysis after the Surgery

Background : With regard to the vascular anatomy, it is well known that a non-recurrent inferior laryngeal nerve(NRILN)is always associated with the aberrant subclavian artery(ASCA). As we previously reported in 2001, preoperative CT scans of the neck allowed us to recognize the ASCA and predict an NRILN. In 2016, we also reported in 2016 that approaching the vagal nerve first before dissecting the paratracheal region is essential for the preservation of the NRILN. As we have practiced these methods, we would like to review our clinical results in NRILN cases retrospectively and to verify the efficacy of this approach in avoiding vocal cord paralysis. Materials and Results: Between May 1995 and June 2016, 2739 patients underwent thyroid or esophageal cancer surgery, in which the right inferior laryngeal nerve was confirmed visually during the surgery. Furthermore, 16 of these patients were diagnosed as having an NRILN. For them, the vagal nerve was approached first in order to preserve the NRILN. Postoperative laryngeal fiberscopy revealed no temporary, incomplete or complete vocal cord paralysis in any of the cases involving patients with the NRILN. Conclusions: The preoperative diagnosis of ASCA, the prediction of an NRILN, and the procedure of approaching the vagal nerve first, were effective for avoiding vocal cord paralysis in the patients with an NRILN. Vocal cord paralysis is an important factor that is associated with the deterioration of a patient’s QOL.