Brinchmann-Hansen O, Myhre K
Eye Department, Ullevål University Hospital, Oslo, Norway.
Aviat Space Environ Med. 1989 Oct;60(10 Pt 1):970-6.
Identical test protocols were used before and after 2 to 7 weeks of high altitude exposure in 23 climbers participating in 3 separate mountain expeditions in the Himalayas. The three groups reached altitudes of 4,000 m, 5,200, and 5,850 m, respectively. High altitude retinal hemorrhages (HARH) were found in three subjects (13%). Two weeks after the mountain exposure, reduced mean values of systolic (p less than 0.005) and diastolic (p less than 0.05) blood pressure and intraocular pressure (p less than 0.005) were found. Retinal veins were dilated 2.6% (p less than 0.001), and in both arteries (p less than 0.001) and veins (p less than 0.005) we observed a tendency for small vessels to dilate and large vessels to constrict. The intensity of reflection of light ("the central light reflex") from arteries was reduced (p = 0.003), indicating hemorrheology changes in the vessels. This study shows that significant changes in blood pressure, intraocular pressure and retinal vascularity follow hypoxic and physical strain of high altitude. The vascular conditioning of altitude acclimatization can be demonstrated in the retinal circulation 2 weeks after the exposure.
在参与喜马拉雅山脉3次不同登山探险活动的23名登山者中，在海拔2至7周的高海拔暴露前后采用了相同的测试方案。三组分别到达了4000米、5200米和5850米的高度。在三名受试者（13%）中发现了高原视网膜出血（HARH）。登山暴露两周后，发现收缩压（p<0.005）、舒张压（p<0.05）和眼压（p<0.005）的平均值降低。视网膜静脉扩张了2.6%（p<0.001），在动脉（p<0.001）和静脉（p<0.005）中，我们都观察到小血管有扩张趋势而大血管有收缩趋势。动脉光反射强度（“中央光反射”）降低（p=0.003），表明血管血液流变学发生变化。这项研究表明，在高海拔低氧和体力负荷后，血压、眼压和视网膜血管会发生显著变化。暴露两周后，在视网膜循环中可以证明高原适应的血管调节作用。
