[Functioning remobilization of the paralyzed vocal cord using the split-vagus nerve procedure in rats the split-vagus nerve procedure in rats].

OBJECTIVE: To locate the recurrent laryngeal nerve fascicles in vagus and investigate the effect of the split-vagus nerve procedure to repair the paralyzed vocal cord in rats. METHOD: The method of dissection and acetylcholinesterase histochemical staining of neural fibers were used to locate the recurrent laryngeal nerve fascicles in vagus. Then 60 SD rats were divided into three groups. In experimental group right recurrent laryngeal nerve were incised and anastomosed to recurrent laryngeal nerve fascicles in vagus by means of the split-vagus nerve procedure. In control group right recurrent laryngeal nerve were incised and sutured immediately by means of end-to-end nerve anastomosis. In normal group rats were not treated by any elements. Three months later, rats from each group were examined for vocal cord movement and nerve regeneration by using fibrolaryngoscope and nerve electromyography. RESULT: The recurrent laryngeal nerve fascicles is in the medial-anterior segment of the vagus and its diameter is about one-fourth as large as the vagus. Three months after operation, the effect of the split-vagus nerve procedure bad not significant difference compared with the control group (P > 0.05). CONCLUSION: The location of the recurrent laryngeal nerve fascicles in vagus provides important anatomical guideline for surgery. The split-vagus nerve procedure has a similar treatment effect compared with end-to-end nerve anastomosis. This microsurgical technique provides a new method for repairing recurrent laryngeal nerve.