兔咬肌原位移植状态下面神经吻合与植入的比较研究

Paralyzed masseter muscle reinnervation by facial nerve implantation or anastomosis:a com-parative study in rabbits

目的探讨失神经支配的咬肌瓣获得面神经再支配后的生理和结构特性变化。方法取24只新西兰大白兔,平均分为两组:A组行面神经———咬肌神经端端移植吻合;B组行面神经咬肌内植入。术后分别在第1、3、6个月进行大体观察及肌湿重测定、电生理检查、酶组织化学检查及超微结构观察。结果失神经咬肌可重获面神经再支配,并在面神经支配下行使收缩功能,肌纤维的组化型别发生改变,从而使咬肌的肌纤维类似于表情肌。两种方法在术后3个月时肌肉传导速度的恢复率有显著差异(P<0.01);术后6个月时两者无显著差异(P>0.05)。结论两种方法结果相似,均能使移植肌重获神经支配,恢复收缩功能。一期手术时,神经肌内植入法与吻合法无显著差异(P>0.05),但该方法简单、损伤小,对临床手术治疗面瘫有一定的借鉴作用。

Objective To investigate the changes in the physiological and structural properties of the masseter muscle after reinnervation through different reinnervation methods. Method Twenty-four adult rabbits were randomly divided into groups A and B (n=12) after the establishment of masseter muscle paralysis, followed by facial nerve anastomosis with the masseteric nerves in group A and facial nerve implantation into the masseter muscle in group B. At 1, 3 and 6 months after the operation, gross observation and wet weight measurement of the muscles were conducted along with myoelectric activity and enzyme- histochemical analyses and ultrastructural observation as well. Results The reinnervation of the masseter muscle by both facial nerve anastomosis and implantation was confirmed and the muscles recovered their motion of contraction activity. Changes took place in the histochemical types of the muscle fibers, which tended to assume the properties typical of facial muscles. Three months after the operation, the muscle fiber conduction velocity recovery after the reinnervation by the two methods was significantly different (P<0.01), but not so till 6 months postoperatively (P>0.05). Conclusion This two methods are both effective in the reinnervation of the muscles, but in one-stage operation, intramuscular nerve implantation is relatively less complicated in operation and causes less damage while producing similar effects to that by nerve anastomosis.