The Eye and the Ear

Abstract

In shape the eye is two overlapping globes, the smaller filled with aqueous humour is the anterior segment containing cornea, iris, ciliary body, lens. The internal layer of the larger posterior segment is the retina (receptors of the retinal nerves), external to this is the choroid. The macula, the sensitive spot, lies on the eye’s central axis. The retinal nerves leave the eye at the optic disc. They form the optic tract, eventually reaching the occipital cortex. Retina and optic disc are part of the brain, swelling of the disc is one of the first signs of raised intercranial pressure. Blood supply, through branches of the ophthalmic artery and vein, is rich, except to the cornea.