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

运用部分膈神经纤维使环杓后肌得到神经支配,从而恢复麻痹喉的吸气性外展功能。用15只猫,在喉内将喉返神经的内收肌支切断后远端结扎,近端埋入环杓后肌中,随后在气管食管间沟内将喉返神经切断,远端和隔神经上支吻合。术后不同时间行直接喉镜检查。喉肌电图检查及组织学检查,证实环杓后肌能建立有效的神经支配,其收缩为膈神经支配的结果;术侧声带呈现规律性的吸气性外展,其外展程度甚至可超过键侧;同时行胸腔内压测定证实隔肌功能无明显下降。

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.