Where do blood vessels enter and exit the eye?

Where do blood vessels enter and exit the eye?

• A. Optic disk
• B. Cornea
• C. Retina
• D. Choroid

Answer: (A)

The key idea is that the optic disk is the doorway for the eye’s blood vessels. The central retinal artery and vein enter and exit the retina by passing through the optic nerve head, which is the optic disk. The cornea is avascular, so it doesn’t serve as a vessel entry point. The vessels that nourish the retina and the choroid stay within their respective layers and do not enter the eye through other surfaces. So the optic disk is the site where these vessels and the nerve itself pass from the inside of the eye to the retina. (That region is also the blind spot because it contains no photoreceptors.)

The key idea is that the optic disk is the doorway for the eye’s blood vessels. The central retinal artery and vein enter and exit the retina by passing through the optic nerve head, which is the optic disk. The cornea is avascular, so it doesn’t serve as a vessel entry point. The vessels that nourish the retina and the choroid stay within their respective layers and do not enter the eye through other surfaces. So the optic disk is the site where these vessels and the nerve itself pass from the inside of the eye to the retina. (That region is also the blind spot because it contains no photoreceptors.)