Central retinal artery occlusion Like anterior ischemic optic neuropathy, central retinal artery occlusion causes sudden, painless loss of vision. Retinal artery occlusions usually result from thrombosis or embolism. Systemic arteriosclerosis is the most common underlying condition. Experimentally, total occlusion of the central retinal artery causes irreversible, complete infarction of the retina within 100 minutes. Nonetheless, it is reasonable to attempt to dislodge the thrombus or clot from the vessel in patients presenting within 24 hours of onset of decreased vision.
Treatment consists of immediate lowering of intraocular pressure or vasodilation, or both.
This approach theoretically reduces resistance to a thrombus or embolus moving distally, thereby limiting the extent of retinal infarction. The simplest method of mechanically lowering intraocular pressure and producing transient vasodilation is alternate compression and rapid decompression of the eye. Firm digital pressure sufficient to produce mild discomfort is applied to the globe for 10 to 15 seconds. Sudden release of pressure produces an immediate decrease in intraocular pressure and vasodilation. This procedure can be repeated multiple times.