Russo A, Agard E, Blein J-P, Chehab H El, Lagenaite C, Ract-Madoux G, Dot C
Service d'ophtalmologie, hôpital d'instruction des armées Desgenettes, 108, boulevard Pinel, 69003 Lyon, France.
Service d'ophtalmologie, hôpital d'instruction des armées Desgenettes, 108, boulevard Pinel, 69003 Lyon, France.
J Fr Ophtalmol. 2014 Oct;37(8):629-34. doi: 10.1016/j.jfo.2014.04.009. Epub 2014 Sep 8.
To report three cases of vision loss occurring at high altitude.
Three patients aged 27 to 52 years presented with scotoma and/or visual acuity deficit upon their return from high altitude expeditions above 6000 m. Fundus examination revealed multiple posterior pole hemorrhages, resolving completely by two months.
Exposure to hypobaric hypoxia at high altitude leads to adaptation mechanisms in order to maintain retinal oxygenation. Certain individuals have an inadequate autoregulatory response and develop signs of "high altitude retinopathy" (HAR), including retinal hemorrhages most often, with occasional vitreous hemorrhage, optic nerve head edema and retinal vein occlusion. The pathophysiology of HAR is not well understood. Identified risk factors include altitude above 4000 m, rapid ascent and personal susceptibility. Age and fitness are unrelated. Association with acute mountain sickness, high-altitude pulmonary edema and high-altitude cerebral edema is still controversial.
Retinal hemorrhages occurring after high-altitude hiking are an early manifestation of HAR and are part of high-altitude illness. HAR usually occurs at altitudes above 4000 m, is generally asymptomatic, and spontaneously regresses. A maladaptive autoregulatory response to hypobaric hypoxia appears to be the cause of HAR.
报告三例在高海拔地区发生视力丧失的病例。
三名年龄在27至52岁的患者在从海拔6000米以上的高海拔探险返回后出现暗点和/或视力缺陷。眼底检查发现多个后极部出血，两个月内完全消退。
在高海拔地区暴露于低压低氧环境会引发适应机制以维持视网膜氧合。某些个体的自身调节反应不足，会出现“高海拔视网膜病变”（HAR）的体征，最常见的是视网膜出血，偶尔伴有玻璃体积血、视神经乳头水肿和视网膜静脉阻塞。HAR的病理生理学尚未完全了解。已确定的危险因素包括海拔超过4000米、快速上升和个人易感性。年龄和健康状况与之无关。与急性高山病、高海拔肺水肿和高海拔脑水肿的关联仍存在争议。
高海拔徒步后发生的视网膜出血是HAR的早期表现，是高海拔疾病的一部分。HAR通常发生在海拔4000米以上，一般无症状，且可自发消退。对低压低氧的适应性自身调节反应不良似乎是HAR的病因。
