Описание

The fovea centralis, also generally known as the fovea (the term fovea comes from the Latin, meaning pit or pitfall), is a part of the eye, located in the center of the macula region of the retina.

The fovea is responsible for sharp central vision (also called foveal vision), which is necessary in humans for reading, driving, and any activity where visual detail is of primary importance.

The fovea is surrounded by the parafovea belt, and the perifovea outer region.The parafovea is the intermediate belt, where the ganglion cell layer is composed of more than five rows of cells, as well as the highest density of cones; the perifovea is the outermost region where the ganglion cell layer contains two to four rows of cells, and is where visual acuity is below the optimum. The perifovea contains an even more diminished density of cones, having 12 per 100 micrometres versus 50 per 100 micrometres in the most central fovea. This, in turn, is surrounded by a larger peripheralarea that delivers highly compressed information of low resolution. Approximately 50% of the nerve fibers in the optic nervecarry information from the fovea, while the other 50% carry information from the rest of the retina. The parafovea extends to a distance of 1¼ mm from the central fovea, and the perifovea is found 2¾ mm away from the fovea centralis.


This definition incorporates text from the wikipedia website - Wikipedia: The free encyclopedia. (2004, July 22). FL: Wikimedia Foundation, Inc. Retrieved August 10, 2004, from http://www.wikipedia.org

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