脑干枪弹伤的超微结构研究

Ultrastructure study of brain-stem gunshot wounds

目的 观察脑干枪弹伤的形态学变化。 方法 切取 2例头部枪弹伤死亡后 2 5min的脑干 ,对中脑与脑桥被盖部和延脑第四脑室深部组织做电镜观察。 结果 中脑枪弹伤波及整个脑干及小脑 ;脑干枪弹伤超微结构见烧灼伤和冲击、压力伤两种 ,其特点是广泛性神经轴索损伤重 ,神经元损伤轻 ;轴索烧灼伤呈现轴索水肿 ,髓鞘、轴浆及其线粒体浓缩、变形 ;冲击、压力伤呈现轴突扭曲、变形、融合、挤压、缺损、破裂致轴浆内容物外流或缺失、错位、神经微丝与微管偏向轴索一侧等。 结论 网状结构严重广泛性神经轴索损伤与对机体的致命性有着重要关系。

Objective To observe the morphological changes of the brain-stem gunshot wounds. Methods The brain stems were taken from 2 patients with gunshot wounds at 25 minutes after death. The tegmentum of the midbrain, the pons and the deep portion of the fourth ventricle base in the medulla oblongata were observed under an electronic microscopy. Results The gunshot wounds in the midbrain extended to the whole brain stem and also to the cerebellum. Burn injury and impact injury were found in the ultrastructure of the gunshot wounds. The characteristics revealed severe and extensive injuries of the axons and relatively mild injuries of the neurons. Burn injury of the axons included edema of the axons, condensation and deformation of the myelin sheath, the axonal cytoplasm and the mitochondria. Impact injury included torsion, deformation, fusion, squeezing, defect and rupture of the axons, inducing the outflow and displacement of the cytoplasm and making the neurofibrils and microtubules move to one side. Conclusions There exists intimate relationship between the severe and extensive axonal injuries in the reticular formation and the death of the patients.