环杓后肌功能重建的实验研究

EXPERIMENTAL STUDIES ON THE REINNERVATION OF POSTERIOR CRICOARYTENOID MUSCLE BY THE UPPER BRANCH OF PHRENIC NERVE

The purpose of this work was to reestablish the respiratory abduction of the paralyzed vocal cord through reinnervation of the posterior cricoarytenoid (PCA) muscle by partial phrenic fibres.In fifteen adult cats the adductor branch of the recurrent laryngeal nerve (RLN) of the right side was cut and its distal end ligated, while its proximal end was implanted into the PCA muscle belly.The whole RLN was then transected in the tracheo-esophageal groove and its distal stump anastomosed to the upper branch of the phrenic nerve.Direct laryngoscopy showed that the inspiratory abduction of the paralyzed vocal cord recovered within 40 d in all cats.80 d later, a larger abducent motion of the glottis was observed on the reinnervated side.Abduction was caused by reinnervation of the PCA muscle from phrenic motoneurons, as demonstrated by laryngeal electromyography and histological testings.The function of the diaphragm was preserved as revealed by monitoring of the intrathoracic pressure.