Risk of injury to the external branch of the superior laryngeal nerve in thyroidectomy.

Abstract

To establish in the Mexican population with thyroid disease the risk of injury to the external branch of the superior laryngeal nerve (EBSLN) based on its anatomical position. Non-randomized comparative clinical trial. Seventy-three patients subjected to thyroidectomy because of thyroid nodule in which the EBSLN was identified and classified. The dependent variable was Cernea's classification of the EBSLN, and the independent variables were weight (in grams) of the nodule, side studied, gender, and age. For statistical analysis, chi2 test, Fisher's Exact test, and analysis of multiple variables (analysis of variance) were used. We studied 73 patients; 64 (87.62%) were women and 9 (12.38%) were men (average age, 39.3 years [age range, 17-73 y]; median age, 40 y; mode, 40 y; SD +/- 23.4 y). Regarding location of the EBSLN, for pathological lobes, 78.1% were located in a high-risk position and for nonpathological lobes, 72.7%. Comparative analysis between sides and relation between weight and classification revealed no statistical significance. The frequency of high-risk position for EBSLN lesion in our milieu was higher than that reported in series from other countries and races.