Nonrecurrent laryngeal nerves and their clinical significance.

The anomalous position of a nonrecurrent laryngeal nerve predisposes the nerve to injury during thyroidectomy and to compression by a thyroid mass. We present three cases in which a seemingly benign thyroid mass traumatized a nonrecurrent laryngeal nerve resulting in either vocal cord paralysis or a vague pressure sensation over the larynx. Some of these patients feel as if they need to clear a foreign body and present with a chronic cough. Normally the nerve is protected from thyroid masses as it passes through the tracheoesophageal groove. In all three patients, surgical excision of the thyroid mass and release of the nerve resulted in recovery of the nerve and resolution of the symptoms. We have found that small, benign, or otherwise asymptomatic lesions of the thyroid gland have a greater tendency to cause vocal cord paralysis in patients with nonrecurrent laryngeal nerves. The surgeon must always be aware of the possibility of the presence of a nonrecurrent laryngeal nerve.