Experimental study of autogenous vein graft connector repairing laryngeal nerve defect in dogs / 中国普通外科杂志

ABSTRACT

Objective To investigate the feasibility of autogenous vein graft as a connector to repair recurrent laryngeal nerve(RLN) defect. Methods 20 healthy dogs were randomly devided into 4 groups group 1(n=6), 2(n=6), 3(n=5) and control group(n=3). Left RLN of dogs in group 1,2,3 were resected for 1,2,3 centimetres respectively and followed by repairment with autogenous vein graft, while RLNS of dogs in control group were resected but not conducted by autogenous vein graft. Six months after operation, the vocal fold movement, phonation and induced action potensial as well as morphologic observation of the aryngeal muslces were studied. Results In group 1, phonation of dogs was all restored to normal. The vocal fold of RLN resected side showed no atrophy symmetrical to the normal side and adducted apparently when phonating. Furthermore thyroarythenoid muscle and posterior cricoarytenoid muscle both could generate induced action potentially. Regenerated nerves in verin graft and distal nerve were observed by light microscope and electron microscope. In group 2,3 and control group hoarseness improved six months after op eration, the vocal fold of RLN resected side was atrophied apparently and fixed paramedianly. Fissure existed in glottis when vocal fold closed, and compensative movement of opposite vocal fold across over the median line was found. Thyoarthenoid muscle and posterior cricoarytenoid muscle unable to generate an action was found. Regenerated nerves were not observed in vein graft or distal nerve by light microscope and electron microscope. Conclusions It is feasible to repair RLN defect in certain length by autogenous vein graft.