흰쥐에서 반회후두신경 손상 후 만성적 전기자극이 후두 기능 회복에 미치는 영향

Effects of Chronic Electrical Stimulation on Functional Recovery Following Laryngeal Reinnervation in the Rat

Background and Objectives : Until now, various attempts have been made fir reinnervating paralyzed vocal cord. Nevertheless, the most cases did not produce satisfactory outcome due to occurrence of synkinesis of larynx secondary to misdirected axonal regeneration. Accordingly, the purpose of this investigation is to learn the effect of chronic electrical stimulation on regeneration of the recurrent laryngeal nerve. Material and Methods : Using 20 healthy male Sprague-Dawley rats(250-300g) with normal vocal functions, transections were made on their left recurrent laryngeal nerves and then primary anastomosis were performed under the operating microscope and they were divided into an experimental group and a control group each having 10 rats. After the procedure, for the experimental group, chronic electrical stimulation was carried out until vocal cord movement was functionally recovered. for the control group, only chronic electrical stimulation was not given. Result : In experimental group, the number of functionally recovered rats was two and in control group, that of functionally recovered rate was same. The reorganization of posterior cricoarytenoid muscle motoneuron in nucleus ambiguus appeared in the case of directed reinnervation of recurrent laryngeal nerve. Conclusion : The chronic electrical stimulation does not a direct beneficial effect on the early functional recovery in rats with injured recurrent laryngeal nerve.