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1. a stain, spot, or thickening; in anatomy, an area distinguishable by color or otherwise from its surroundings. Often used alone to refer to the macula retinae.
2. a discolored spot on the skin that is not raised above the surface; called also macule.
3. a corneal scar that can be seen without special optical aids; it presents as a gray spot intermediate between a nebula and a leukoma.
4. macula lutea. adj., adj mac´ular, mac´ulate.
macula atro´phica a white atrophic patch on the skin.
macula ceru´lea a blue patch on the skin seen in pediculosis.
macula cribro´sa a perforated spot or area; one of three perforated areas (inferior, medial, and superior) in the wall of the vestibule of the ear through which branches of the vestibulocochlear nerve pass to the saccule, utricle, and semicircular canals.
macula den´sa a zone of heavily nucleated cells in the distal renal tubule that feed information to the juxtaglomerular cells.
macula fla´va a yellow nodule at one end of a vocal cord.
macula folli´culi follicular stigma.
macula germinati´va germinal area; the part of the ovum where the embryo is formed.
macula lu´tea (macula lu´tea re´tinae) (macula re´tinae) an irregular yellowish depression on the retina, lateral to and slightly below the optic disk; receives and analyzes light only from the center of the visual field.
macula sac´culi a thickening on the wall of the saccule where the epithelium contains hair cells that receive and transmit vestibular impulses.
macula utri´culi a thickening in the wall of the utricle where the epithelium contains hair cells that are stimulated by linear acceleration and deceleration and by gravity.
macula of retina[TA]
an oval area of the sensory retina, 3 × 5 mm, temporal to the optic disc corresponding to the posterior pole of the eye; at its center is the central fovea, which contains only retinal cones.
n. pl. maculae luteae (lo͞o′tē-ē′)
A minute yellowish area containing the fovea centralis located near the center of the retina of the eye at which visual perception is most acute. Also called yellow spot.
macula luteaA yellowish depression on the retina which contains the fovea centralis, the area of sharpest vision.
macula luteaThe yellow spot in the centre of the RETINA on which the image of the point of greatest visual interest falls when something is observed. The macula is the most sensitive part of the retina and is devoid of blood vessels. Here, the concentration of colour-sensitive cones is maximal and the visual resolution is greatest. The full visual acuity is possible only by the use of the centre of the macula—the fovea.
An oval area of the retina 3-5 mm in diameter, with the foveal depression at its centre, slightly below the level of the optic disc and temporal to it (its centre lies 3.5 mm from the edge of the disc). The side wall of the depression slopes gradually towards the centre where the fovea centralis is located and where the best photopic visual acuity is obtained. Around the fovea, the ganglion cells are much more numerous than elsewhere, being arranged in five to seven layers. The outer molecular layer is also thicker than elsewhere and forms the outer fibre layer of Henle and there is a progressive disappearance of rods so that at the foveola only cones are found. The area of the macula lutea is impregnated by a yellow pigment (macular pigment) in the inner layers and for that reason is often called the yellow spot. Syn. area centralis (although that area is considered to be slightly larger, about 5.5 mm in diameter); punctum luteum. See blue field entoptoscope; fovea centralis; macular pigment.