Misdirected reinnervation in the feline intrinsic laryngeal muscles after long-term denervation.

Nerve terminals which resembled the autonomic nerve varicosities were found at all neuromuscular junctions of the feline intrinsic laryngeal muscles after 21 months of unilateral laryngeal paralysis. The structure of muscle fibers was preserved throughout this period, although there was no evidence of regeneration of transected recurrent laryngeal nerve. In the cricothyroid muscle, misdirected reinnervation was recognized in the different pathways from the other intrinsic laryngeal muscles.