netvlies

The netvlies, or retina, is the light-sensitive tissue that lines the back of the eyeball. It detects light and converts it into electrical signals that are transmitted to the brain via the optic nerve, enabling visual perception. It lies between the vitreous humor in front and the choroid and pigmented epithelium behind.

The retina contains photoreceptor cells—rods and cones—that detect light intensity and color, respectively. The neural retina comprises several layers, including the outer nuclear layer (photoreceptor cell bodies), outer plexiform layer (synapses between photoreceptors and bipolar/horizontal cells), inner nuclear layer (bipolar, horizontal, and amacrine cells), inner plexiform layer (connections to ganglion cells), and the ganglion cell layer, whose axons form the optic nerve. The outer pigmented epithelium absorbs excess light and supports photoreceptors.

The macula, and especially the fovea centralis, provide high-acuity central vision due to a high density of cones. The retina receives blood supply from the choroid (outer retina) and the central retinal artery (inner retina). The retina integrates visual information before it exits the eye as the optic nerve.

Clinically, degeneration or detachment of the retina, diabetic retinopathy, age-related macular degeneration, and retinitis pigmentosa can impair vision. Advances in imaging and treatments address various retinal diseases, including laser therapies and injections that target abnormal blood vessel growth or retinal repair.