兔视神经间接损伤后视觉电生理及视神经超微结构观察  

Recovery and regeneration of the optic nerve following indirect injury in adult rabbit

作　　者：孙瑞霞[1] 张东杲[2] 马志中[3] 

机构地区：[1]广州军区总医院整形科,510010 [2]第四军医大学唐都医院眼科 [3]解放军总医院眼科

出　　处：《中国实用眼科杂志》2002年第11期861-864,共4页Chinese Journal of Practical Ophthalmology

摘　　要：目的 :视神经间接损伤在闭合性颅脑外伤中占到 5 % ,但是有关其临床治疗仍存在较大分歧。因此探讨视神经间接损伤后形态学的演变 ,为临床治疗提供相关的理论依据 ,具有重要的意义。方法 :在成年兔的视神经间接损伤模型上 ,动态观察视觉电生理 (F -VEP)的变化 ,同时结合视神经的超微结构变化了解视神经间接损伤后形态学的演变。结果 :间接损伤后损伤眼的F -VEP的P1峰幅值比对照眼下降 47 3 8% ,峰潜时延长 ,伤后 1～ 2周时变化更为明显 ,伤后 4周时F -VEP开始恢复 ,8周时P1峰幅值明显提高 ,峰潜时缩短 ,12周时稳定 ,接近正常水平。间接损伤后视神经的超微结构变化主要表现为轴突肿胀 ,髓鞘疏松 ,板层脱离 ,毛细血管破裂出血 ,胶质细胞核内染色质浓缩 ,胶质细丝溶解。这些改变 2周时最重 ,4周时部分轴突开始修复 ,8～ 12周时部分轴突明显修复 ,同时有大量胶质纤维填补变性坏死的轴突留下的空隙。结论 :本实验条件下间接损伤后的视神经其视功能可以逐渐恢复 ,超微结构的观察证明间接损伤的视神经有一定的修复能力 ,这构成视功能恢复的基础。Objective:Approximately 5% of all patients with closed head trauma manifest an indirect injury to the optic nerve.It is important to study the morphology after injury,which might offer some information for the treatment of optic nerve injury. Methods:Indirect optic injury models were made in adult rabbits.The dynamic observation of Flash-VEP and the ultrastructure of injured optic nerve were carried out to realize the morphological changes. Results:The amplitude of P1 decreased 47 38% in injured eyes comparing with that in control eyes and tend to be lowest at 1～2 weeks after injury,while P1 latency was delayed.Recovery of F-VEP in the injured eyes began from the 4th week after injury.Amplitude of P1 was more larger at the 8th week than that at 1～2 weeks and tend to be normal at the 12th week,P1 latency shortened.The ultrastructural changes of optic nerve were mainly axonal swelling,myelinic degeneration and capillary hemorrhage.Nuclear chromatins of asstrocyte concentration and glia filament fusion were also seen.The conditions get more serious at the 2nd week after injury.Some axons began restored at the 4th week and recovering at 8～12 weeks,at the same time,other axon degenerated and disappeared,while glia fibril filled the space. Conclusions:The visual function of the post-indirect injured optic nerves of the rabbits can get gradually recovery.The observation of the ultrastructure also proved that the indirect injured optic nerves have the ability of automatic recovery and it is the base of visual functional recovery.

关 键 词：视神经 间接损伤 F-VEP 超微结构 

分 类 号：R774.6[医药卫生—眼科]