颈内动脉压迫视神经颅内段的组织学改变及其机制

目的:观察视神经受压后的组织学改变,探讨因压迫所致视野缺损发生的机制。方法:60-80岁的老年人脑,组织切片观察颈内动脉内膜钙化压迫视神经颅内段引起的神经组织学改变。结果:粥样硬化的颈内动脉可压迫视神经并在其表面形成明显压迹。神经受压后,中隔变窄,神经束呈条索状,束内营养小动脉硬化,管腔阻塞,节细胞轴突萎缩,重者可全部消失,少突胶质细胞增多,肿胀。结论:视神经纤维萎缩是由于阻塞了神经束内营养小动脉缺血所致,以乳头黄斑束受累为甚,是视野缺损发生的原因之一。

Histological changes of human intracranial optic nerve induced by compression of internal carotid artery and its mechanism

Objective: To explore the mechanism of visual field deficit through compressing the optic nerve by internal carotid atherosclerosis. Methods: Sixty sides of human brain (aged from 60-80, male: 36, female: 24) were fixed by formalin. The compression on the optic nerve was induced by the sclerosed internal carotid arteries and structure changes of optic nerve were observed pathohistologically. Results: Optic nerve was compressed by sclerosed internal carotid arteries. There were changes with different shape, size and depth on the surface of optic-nerve. Pathological changes of optic nerves included fiber cluster of optic nerves became striplike. Some nerve fiber was dense or sparse. Arteries among nerve bundles were calcified, narrowing the vessel cavity. Nerve axon was denatured, myelin sheath was broken, glial cells were swollen, cell nucleus was dissolved, and nerve fiber was atrophied greatly. Conclusion: The atherosclerosis of internal carotid arteries might press the thin arteries of optic nerve, which can cause the denaturalization or atrophy of optic nerve, and it is one of the reasons for visual field deficits.