外伤性脑梗死的形态学观察

目的 观察外伤性脑梗死的形态学特点,并探讨其与脑挫伤的鉴别。方法 从81例重型颅脑损伤中选出15例符合继发性出血坏死标准的脑标本,另选15例脑挫伤标本作对照,两者均经福尔马林固定后分别作冠状、矢状及水平切面,用肉眼与光镜观察。结果 外伤性脑梗死常见于5个部位,即基底节(3例)、扣带回(2例)、对称性枕部楔叶回(2例)、枕颞外侧回(6例,5例合并有中脑桥脑出血)和枕回(2例);梗死均不在直接受力点或其对冲点,范围明确局限,呈楔形或类楔形,且与脑疲密切相关。镜下见梗死区高度淤血、出血及坏死;水肿,并有白细胞浸润和胶质细胞反应。大脑各叶的梗死,严重者累及全皮层与蛛网膜下腔,未见软脑膜破裂;神经细胞缺氧或缺血性病变明显。脑挫伤的案例,见受力点或对冲部位的皮质及皮质下髓质处出血,挫伤处脑回顶部的软脑膜多破裂,挫伤的脑组织可有挫烂。结论 外伤性脑梗死在法医学上习惯称为继发性出血坏死;它是由于脑疝和水肿压迫颅内血管而形成。外伤性脑梗死和脑挫伤,根据其与脑疝的关系、病变部位、软脑膜是否完整,以及其它组织学改变,二者不难鉴别。

Morphologic study of the post-traumatic cerebral infarction

Objective To observe the morphologic characteristics of the post-traumatic cerebral infarction and discriminate it from brain contusion. Methods From 81 severe brain injury samples 15 were selected which met the criteria of the secondary necrosis and hemorrhage of brain. Another 15 simple brain contusion samples were selected as control. They were cut according to various requirements either coronary or saggittally or horizontally and observed grossly and histologically. Results The post-traumatic cerebral infarctions were found mainly in 5 localities: basal ganglia (3 cases), cingulate gyrus (2 cases), both cuneus of the occipital lobes (2 cases), lateral occipito-temporal gyrus (6 cases, 5 of them complicated with hemorrhage in the midbrain and pons), and occipital gyrus (2 cases). All of the infarctions were located not at the point of coup or contrecoup. They were localized and had clear boundaries. All of the lesions could be traced back to be related to brain hernia. Microscopically, there were extravasation of blood, and necrosis in the infarction, and usually severe congestion and edema with white blood cells infiltration and glia cell reaction. If the lesion was in the cerebrum, it was usually located at the junction of cortex and medulla, in severe cases extended to whole thickness of the cortex and the subarachnoid space, but the pia mater was not ruptured. There were marked ischemic and hypoxia changes in the neurons. The lesions of brain contusion, on the contrary, were always ruptured. The contused brain tissue may be necrotic. Conclusion The Post-traumatic cerebral infarction is synonymous with secondary necrosis and hemorrhage of the brain. The mechanism of the infarction is compression of intra-cerebral blood vessels due to cerebral hernia. It could be differentiated from cerebral contusion by the relation with cerebral hernia, the location of the lesion, the in-tactness of the pia mater, as well as other related histological changes.