Preservation Technique for External Laryngeal Nerve in Thyroid Surgery

Abstract

A prospective comparative study conducted at Basrah Teaching Hospital in Basrah between December 2000 and February 2002. Eighty patients included, they were 13 (16.2%) male and 67(83.7%) female patients, most of the patients aged between 20-50 year (81%). The patients were allocated in two groups, each comprises 40 patients. The external laryngeal nerve (E.L.N) is a motor nerve to cricothyroid muscle of the larynx which concerned with high pitch voice. The incidence of injury to this nerve during thyroid surgery is between 11-25% in the literature. This study aimed to compare the incidence of ELN injury in thyroid surgery between the ordinary approach and the nerve stimulator approach in two groups, and to evaluate the efficacy of nerve preservation technique using nerve stimulator. In the first group, thyroid surgery was done with the aid of nerve stimulator, while in the second group the surgery was done in classical way; we found that the incidence of ELN injury in rthe first group was zero while in the second group was 12.5% (5/40). We Also found increase risk of injury to ELN in thyrotoxic patient and it was about 30.7% (4/13). We concluded that nerve stimulation is an effective method for preservation of ELN in thyroid surgery and we recommend its use in every thyroidectomy specially in cases having thyrotoxicosis, thyroiditis, huge goitre and in certain professional groups like teachers, lectureres singers and female patients.