Mancha

Human eye cross-sectional view. The macula or macula lutea (from Latin macula, "mancha" + lutea, "amarillo") is an oval yellow spot near the center of the retina of the human eye. It has a diameter of about 1.5 mm and is often histologically defined as having two or more layers of ganglion cells. Near its center is the fovea, a small pit that contains the largest concentration of cone cells in the eye and is responsible for central vision. It is specialized for high acuity vision. Within the macula are the fovea and foveola which contain a high density of cones (photoreceptors with high acuity). Whereas loss of peripheral vision may go unnoticed for some time, damage to the macula will result in loss of central vision, which is usually immediately obvious. The progressive destruction of the macula is a disease known as macular degeneration. Visual input to the macula occupies a substantial portion of the brain's visual capacity. Como resultado, some forms of visual field loss can occur without involving the macula; this is termed macular sparing. (Por ejemplo, visual field testing might demonstrate homonymous hemianopsia with macular sparing.) This finding can be very informative for the ophthalmologist. See also Cystoid macular edema Intermediate Uveitis Macula Additional images The interior of the posterior half of the left eyeball. Sistema sensorial - Sistema visual - Eye - edit Anterior chamber| Aqueous humour| Blind spot| Choroid| Ciliary body| Conjunctiva| Cornea| Iris| Lens| Mancha| Optic disc| Optic fovea| Posterior chamber| Pupil| Retina| Schlemm's canal| Sclera| Tapetum lucidum| Trabecular meshwork| Vitreous humour Sensory system - Sistema visual - edit Eye| Optic nerve| Optic chiasm| Optic tract| Lateral geniculate nucleus| Optic radiation| Visual cortex This page uses Creative Commons Licensed content from Wikipedia (ver autores).