What is the primary anatomical cause of CRAO?

The primary anatomical cause of Central Retinal Artery Occlusion (CRAO) is the blockage of blood flow through the central retinal artery. This obstruction can result from various factors, including embolism, thrombosis, or atherosclerosis. The central retinal artery supplies essential nutrients and oxygen to the inner layers of the retina, and when it is occluded, it leads to rapid and severe vision loss in the affected eye.

Understanding the critical role of the central retinal artery in maintaining retinal health helps clarify why its blockage is the core issue in CRAO. The retina is highly sensitive to ischemia; thus, any interruption of blood flow can lead to significant damage and potential permanent vision loss. Other options, while they may be related to retinal health, do not directly cause CRAO. Options like increased intraocular pressure are related to conditions such as glaucoma, while displacement of the optic nerve and malformation of the retinal structure involve different pathophysiological mechanisms and are not the primary anatomical reasons for CRAO.