爆炸伤对犬面神经影响的实验研究

The Experimental Study of the Effect of the Blast Injury on the Dog's Facial Nerve

目的建立面神经爆炸伤动物模型,并研究面神经爆炸伤特点及相关的全身反应。方法麻醉下分别在距犬面部7、10、15cm处放置雷管,模拟爆轰波致伤效应,在雷管爆炸同时,用滑膛枪发射钢珠弹致伤犬同侧咬肌或颈部以模拟破片致伤。观察动物伤情,并取材检测面神经病理和传导速度改变,分析不同距离条件下全身和局部的创伤效应。结果7cm致伤时动物伤情较重,不能存活较长时间;10cm致伤时动物经过抢救仍可存活,受伤的面神经干肿胀,外膜不光滑,神经干内弥漫性出血。镜下表现为广泛的神经纤维断裂、坏死,并由大量炎细胞弥散浸润;单纯爆炸、15cm处爆炸复合面部破片或10cm处爆炸复合颈部破片致伤时,局部伤情均较轻。随着创伤的恢复,面神经传导速度也逐渐恢复。结论采用距爆源10cm,咬肌切线伤的致伤条件能最好地模拟爆炸条件对面神经的致伤作用,这种致伤条件接近实战情况,并利于伤后长期观察面神经创伤的预后和转归。

Objective To find an animal model to imitate the facial nerve injury of explosion and observe the animal's local and general effect after injury. Methods The impact wave was simulated by detonator blast in the distance of 7cm, 10cm and 15cm of dogs under anesthesia. At the same time, the masseter or the neck was wounded by a rifle-shot steel ball to imitate fragments in the real explosions. The facial nerve was taken to observe the pathological and electrophysiological changes to analyze the wound effect of different distances. Results The animal was injured severely in the distance of 7cm and could not survive for long time. The dog injured at 10cm could survive after emergency treatment, and there was diffusing hemorrhage in the edematous nerve trunk. Under light microscope, the breaking and necrosis of the facial nerve fibers could be widely observed with infiltrating inflammatory cells. The dog was injured lightly in the condition of simple blast, blast at 15cm with fragment shot at masseter and blast at 10cm with fragment shot at neck. The facial nerve conduction velocity could recover with the healing of trauma. Conclusions The dog's traumatic model founded by 10cm-blast with the edge fragment injury of masseter is an appropriate animal model for the research of facial nerve explosive injury, because of reliability to observe the prognosis of injured facial nerves.