page_title: Fovea centralis
section_title: Properties
hierarchical_section_title: Fovea centralis / Structure / Properties
caption_attribution_description: English: Histology of Macula in OCT
context_page_description: The fovea centralis is a small, central pit composed of closely packed cones in the eye. It is located in the center of the macula lutea of the retina.
  The fovea is responsible for sharp central vision, which is necessary in humans for activities for which visual detail is of primary importance, such as reading and driving. 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 layers 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 layers 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. That, in turn, is surrounded by a larger peripheral area, which delivers highly compressed information of low resolution following the pattern of compression in foveated imaging.
context_section_description: Anatomical macula / macula lutea / area centralis (clinical: posterior pole):
  Diameter = 5.5mm (~3.5 disc-diameters) (about 18 deg of VF)
  Demarcated by the superior and inferior temporal arterial arcades.
  Has an elliptical shape horizontally.
  Histologically the only region of the retina where GCL has >1 layer of ganglion cells
  Yellowish appearance = luteal pigments (xanthophyll and beta-carotenoid (Beta-Carotene) in the outer nuclear layers inward.
  Anatomical perifovea:
  Region between parafovea (2.5mm) and edge of macula
  GCL has 2–4 layers of cells.
  12 cones / 100 um
  Anatomical parafovea:
  Diameter = 2.5mm.
  GCL has >5 layers of cells, and highest density of cones
  Anatomical fovea / fovea centralis (clinical: macula)
  Area of depression in the centre of the macula lutea.
  Diameter = 1.5mm (~1 disc-diameter) (about 5 deg of VF)
  Foveal avascular zone (FAZ)
  Diameter = 0.5mm (about 1.5 deg of VF)
  Approximately equal to the foveola
  Anatomical foveola (clinical: fovea)
  Diameter = 0.35mm (about 1 deg of VF)
  the central floor of depression of fovea centralis
  50 cones / 100 um
  Highest visual acuity
  Anatomical umbo
  Represents the precise center of the macula
  Diameter = 0.15mm
  Corresponds to the clinical light reflex
caption: macula histology (OCT)
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