The superior laryngeal nerve in thyroidectomy.

In a clinical prospective study, three cases of superior laryngeal nerve injury were detected after 54 classical high ligations of the superior thyroid artery. On the contrary no injury of the nerve was noted in 227 cases in which the technique of separate ligation of the superior thyroid artery's branches was used. Voice changes secondary to thyroid gland operations, without injury to the recurrent laryngeal nerve, are commonly attributed to laryngeal trauma or tracheitis. This view does not seem to be entirely true, because voice changes can follow injury to the external branch of the superior laryngeal nerve. The current study was undertaken to give a better insight to the problem on injury to the external branch of the superior laryngeal nerve during superior thyroid artery ligation and to evaluate for this purpose a technique of separate ligation of the superior thyroid artery's branches during thyroidectomy.