1. VASCULAR SYSTEM OF THE EYE

In the field of ophthalmology, a beneficial effect of hyperbaric oxygenation therapy has been described for retinal artery occlusions, non-arteriitic optic neuropathy and macular edema secondary to retinal vein occlusion or uveitis. Here we describe the pathology of retinal vascular occlusions and discuss the use of HBO in these conditions The arterial vascular system of the eye derives from branches of the ophthalmic artery which is fed from the internal carotid artery. Before entering the eye, one branch is following the optic nerve into the eye to feed as the central retinal artery the inner retina. Other branches of the ophthalmic artery penetrate the sclera as short and long ciliary arteries to feed the choroid which is supplying the outer retina. Therefore, the retina has two vascular systems each supplying half of the retina. The venous system drains with its branch retinal veins converging to the central retinal vein the inner retina. The central retinal vein passes through the optic nerve together with the central retinal artery and later drains into the ophthalmic vein. The venous system of the choroid drains through four vortex veins through the