这是微信上的一道题，本来我们眼科是考察科目，也刚考完，我也没打算学眼科，不过多一点知识总归是好的。 看了下回复，有人选择了D。那么下面就一一过，涨涨姿势。 首先就是D选项： Central Retinal vein Occlusion 闪爆了（(*^__^*) 嘻嘻……） 视网膜中央静脉闭塞（CRVO）多为单眼发病，眼底检查表现为各象限视网膜静脉迂曲扩张，视网膜内出血呈火焰状，沿视网膜静脉分布，视网膜静脉是如何分布的呢？看下图：
The inner layers of the retina receive their blood supply from the central retinal artery. The blood returns to the heart through the central retinal vein. Both vessels enter the eye through a small opening in the middle of the optic nerve. Either because this opening shrinks or because the artery hardens or becauseof circulations problems, the central retinal vein can become partially or completely occluded. The retinal veins dilate and their are retinal hemorrhages. Patients often develop swelling of the central retina-cystoid macular edema--causing some of the vision loss. 由于视网膜中央静脉阻塞，静脉回流受阻，出现淤血性出血和水肿，出血沿着静脉分布而由于RV的分布是的眼底观察就像是火焰在燃烧。
The circulation to the retina enters the eye through the central retinal artery. When a patient develops a sudden occlusion of the central retinal artery, the vision suddenly and severely declines. Research has shown that retinal cells become irreversibly damaged after the vessel is occluded for more then 45 minutes.
巨细胞病毒视网膜炎（ Cytomegalovirus retinitis， CMV Retinitis）这个，说实话，我没学过，书上也没有，对于非眼科的医学生来说难度有点大，鉴于文章的完整性还是写点吧。 说白了，其实就是个病毒感染也没必要这么矫情。一些人也没有症状，其余主要是：盲点，视物模糊，飞蚊症。通常单眼发病，随着病情进展二双眼发病，如若放弃治疗，4~6个月就会导致视网膜损伤而致盲（多么痛的领悟o(╯□╰)o）CMV感染的患者有可能视网膜脱离，这。。。。 Some people with CMV retinitis have no symptoms. Symptoms include:
Blurred vision and other vision problems
Retinitis usually begins in one eye, but often progresses to the other eye. Without treatment, progressive damage to the retina can lead to blindness in 4-6 months or less. Even with regular treatment, the disease can worsen to blindness. This may be because the virus becomes resistant to the drugs so that the drugs are no longer effective, or because the patient's immune system has deteriorated further. Patients with CMV retinitis also have a chance of developing retinal detachment, in which the retina detaches from the nerves of the eye, causing blindness. Systemic CMV infection also can occur.
好吧，分为几个期，大家百度去吧。 As the optic nerve sheath is continuous with the subarachnoid space of the brain (and is regarded as an extension of the central nervous system), increased pressure is transmitted through to the optic nerve. The brain itself is relatively spared from pathological consequences of high pressure. However, the anterior end of the optic nerve stops abruptly at the eye. Hence the pressure is asymmetrical and this causes a pinching and protrusion of the optic nerve at its head. The fibers of the retinal ganglion cells of the optic disc become engorged and bulge anteriorly. Persistent and extensive optic nerve head swelling, or optic disc edema, can lead to loss of these fibers and permanent visual impairment.