UNILATERAL VOCAL FOLD PARESIS - CORRELATI ONS BETWEEN LARYNGOSCOPIC AND ELECTROMYOGRAPHIC FINDINGS

From a clinical point of view, unilateral vocal fold paresis means tha t one of the vocal folds shows reduced mobility. Etiology may be mecha nical or supranuclear, but in most cases it is a partial peripheral ne urogenic lesion in the muscles innervated by one of the recurrent lary ngeal nerves. On the one hand, a retrospective analysis was made of 71 cases with laryngoscopically reduced mobility of one vocal fold: 58 p atients had electromyographic signs of partial denervation; 13 had nor mal electromyographic activity. Possible explanations are mechanical f actors, paradoxical reinnervation, or central neurological pathology. On the other hand we reviewed 179 cases with an electromyographic diag nosis of unilateral partial peripheral neurogenic lesion in the muscle s innervated by one of the recurrent laryngeal nerves: 119 patients sh owed a clinically immobile vocal fold, 2 a normally moving vocal fold and 58 a paretic vocal fold. A lot of immobile vocal folds are thus pa rtial denervations. Insufficient amount of functional motor units and paradoxical reinnervation provide possible explanations.