Retinal leakage in retinal vein occlusion: reduction after hyperbaric oxygen

A 54-year-old woman with a history of bilateral central retinal vein occlusion, probably due to an inflammatory process, developed a hemispheric retinal vein occlusion with cystoid macular edema in her only seeing eye. Five months later, in the absence of improvement in vision and macular edema, she received on two occasions a 2-weekly course of twice daily 100% hyperbaric oxygen. After each course retinal leakage, as assessed by vitreous fluorophotometry, decreased from abnormal to the normal range while visual acuity improved by two lines. The possible implications are discussed.