Study of Retinal Oxygenation in Central Retinal Vein Occlusion

Inclusion Criteria: * Suspected central retinal vein occlusion. * Informed consent for participation. * No treatment before the first oximetry measurement. Exclusion Criteria: * History of other retinal disease. Glaucoma and diabetes without retinopathy are not exclusion criteria but should be registered. * History of cardiovascular or respiratory diseases that can be expected to influence systemic or retinal oxygen saturation. Examples: Known COPD or carotid stenosis. Subjects with high blood pressure will not be excluded but blood pressure should be registered. * Poor quality images will be excluded based on the images themselves. Therefore, grading of cataract or other media opacities is not strictly necessary for the purpose of the study.