Nimodipine improves regeneration and neuromuscular function following RLN injury in the adult rat, and could be of use in future strategies following RLN injury.

In contrast to previous reports, our results show that laryngeal electromyography is a reliable tool for diagnosing the type of injury within the injured RLN, making it possible to predict the functional outcome in these patients. On the basis of the results, a future randomized study on nimodipine treatment for RLN axonal injury is suggested.

To investigate the prevalence of asymmetries at vocal fold adduction, 109 vocally healthy subjects between 22 and 80 years of age were examined. All subjects were examined with a rigid endoscope and video recorded. The recordings were analysed off line by two laryngologists. Seventy percent of the subjects displayed some kind of asymmetry. There was no difference between the sexes. Side differences in antero-posterior position of the corniculate or cuneiform tubercles were the most frequent asymmetries, occurring in 66% of the total material and in 92% of the asymmetrical cases. Asymmetries appeared more common and more marked in older subjects and possibly more frequent in singers than in non-singers. Laryngeal adduction asymmetries are probably of little importance for voice function.

Transection of the recurrent laryngeal nerve leads to permanent palsy of the vocal cord. Experimental studies have confirmed that nimodipine increases the pace of axonal regeneration. We present a case of a 19-year-old male, suffering a thyroid cancer disease, who was subjected to unilateral resection of the recurrent laryngeal nerve during surgery. The nerve was repaired with a nerve graft and the patient further treated with nimodipine for 3 months. Evaluation of the patient showed normalization of voice, movement of the vocal cord on the injured side, and electromyography evidence of reinnervation of the larynx muscles at 15 months after surgery.

The dual innervation pattern from both laryngeal nerves supports the concept of a laryngeal nerve plexus. The motor input through the external branch of the superior laryngeal nerve was surprisingly high. The animal model presented here may be used in future investigations of laryngeal reinnervation following nerve injury.