Glaucoma is a disease of the eye characterized by increased intraocular pressure (IOP), degeneration of the optic disk and optic nerve fiber damage which produces characteristic defects in the visual field. These defects are thought to be a result of mechanical damage or ischemic damage occurring at the optic disk secondary to elevated IOP. Recently, certain components of the electroretinogram (ERG) have been shown to be extremely sensitive to retinal hypoxia. It is thought that these ERG changes reflect slowing of the highly metabolic Na+/K+ pump of the photoreceptor inner segments. Elevated IOP is known to decrease choroidal blood flow. The experiments in this thesis try to determine if moderately elevated IOP causes photoreceptor hypoxia secondary to decreased choroidal flow. The effects of elevated IOP on the hypoxia-sensitive components of the ERG (c-wave and standing potential) and retinal oxygen distribution was studied in cats during dark-adaptation. ERG changes during elevated IOP were similar to those seen during systemic hypoxia, were reversed during systemic hyperoxia, occurred at much lower IOPs than was previously thought and were found to correlate well with decreases in choroidal PO
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机译：青光眼是一种眼疾病，其特征在于眼内压（IOP）升高，视盘变性和视神经纤维损伤，从而在视野中产生特征性缺陷。这些缺陷被认为是由于IOP升高继发于视盘的机械损伤或缺血损伤的结果。最近，视网膜电图（ERG）的某些成分已显示出对视网膜缺氧极为敏感。认为这些ERG变化反映了感光器内部节段的高代谢Na + / K +泵的减慢。已知眼压升高会降低脉络膜血流。本文的实验试图确定眼压升高是否适度引起脉络膜血流减少继发的光感受器缺氧。在黑暗适应过程中，研究了猫眼中IOP升高对ERG缺氧敏感成分（c波和站立电位）和视网膜氧分布的影响。眼压升高时的ERG改变与全身性缺氧时相似，在系统性高氧时逆转，发生时的眼压低得多，且与脉络膜PO降低密切相关
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