Novack R L, Stefånsson E, Hatchell D L
Duke University Eye Center, Durham, NC 27710.
Exp Eye Res. 1990 Mar;50(3):289-96. doi: 10.1016/0014-4835(90)90213-e.
Panretinal photocoagulation has been shown to raise preretinal oxygen tension in cats and monkeys breathing 100% oxygen. However, in normoxia, there is no significant difference between normal and photocoagulated areas. This is thought to be due to autoregulatory vasoconstriction of the retinal circulation. In avascular rabbit retina, photocoagulation effects on retinal oxygenation can be studied without the influence of retinal vascular autoregulation. We measured normoxic preretinal oxygen tension of normal and photocoagulated rabbit retina at 1, 7, 14 and 28 days after photocoagulation using polarographic oxygen electrodes. For all time points, preretinal oxygen tension of photocoagulated retina (42 +/- 14 torr; mean +/- S.D.) was higher than untreated retina (14 +/- 10 torr; mean +/- S.D., P less than 0.001). Light and electron microscopy of lasered retina showed that the improved oxygenation corresponded to loss of mitochondria-rich inner segments of the photoreceptors.
已证实在吸入100%氧气的猫和猴子中，全视网膜光凝可提高视网膜前氧张力。然而，在常氧状态下，正常区域和光凝区域之间没有显著差异。这被认为是由于视网膜循环的自动调节性血管收缩所致。在无血管的兔视网膜中，可以在不受视网膜血管自动调节影响的情况下研究光凝对视网膜氧合的作用。我们使用极谱氧电极在光凝后1天、7天、14天和28天测量了正常和光凝兔视网膜的常氧视网膜前氧张力。在所有时间点，光凝视网膜的视网膜前氧张力（42±14托；平均值±标准差）高于未处理的视网膜（14±10托；平均值±标准差，P<0.001）。激光照射视网膜的光镜和电镜检查显示，氧合改善与光感受器富含线粒体的内节丢失相对应。
