[Electrodiagnostic and histochemical studies on the effect of electric stimulation on the atrophy of denervated laryngeal muscles in animal experiments].

UNLABELLED: Electrodiagnostic and histometric investigations have been carried out on 56 adult male rabbits following unilateral paralysis of the recurrent laryngeal nerve. Exponential current impulses were externally applied. The excitation threshold was determined endoscopically and also described graphically in terms of the excitation intensity as a function of time (I/t-curves). The diagnostic results thus obtained permit determination of the corresponding excitation parameters for therapy. The success of the therapy was evaluated from histometric data on type I and type II fibres of the vocalis and the posterior cricoarytenoid muscles.
RESULTS: 1. The stimulation of denervated laryngeal muscles by external application of exponential current impulses is selective. 2. The extent of the neurogenous atrophy of denervated muscles following paralysis of the recurrent nerve can be diagnosed electrically. 3. This atrophy could be significantly reduced by proper choice of stimulation parameters within the time span of the experiment (28 days).