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DictionarySeescotomaEncyclopediaSeeScotomaring scotoma
scotoma [sko-to´mah] (Gr.) 1. an area of lost or depressed vision within the visual field, surrounded by an area of less depressed or of normal vision.2. mental scotoma. adj., adj scotom´atous.absolute scotoma an area within the visual field in which perception of light is entirely lost.annular scotoma a circular area of depressed vision surrounding the point of fixation.arcuate scotoma an arc-shaped defect of vision arising in an area near the blind spot and extending toward it.central scotoma an area of depressed vision corresponding with the fixation point and interfering with or abolishing central vision.centrocecal scotoma a horizontal oval defect in the visual field situated between and embracing both the fixation point and the blind spot.color scotoma an isolated area of depressed or defective vision for color in the visual field.hemianopic scotoma depressed or lost vision affecting half of the central visual field; see also hemianopia.mental scotoma in psychiatry, a figurative blind spot in a person's psychological awareness, the patient being unable to gain insight into and to understand his mental problems; lack of insight.negative scotoma a scotoma appearing as a blank spot in the visual field; the patient is unaware of it, and it is detected only by examination.peripheral scotoma an area of depressed vision toward the periphery of the visual field.physiologic scotoma that area of the visual field corresponding with the optic disk, in which the photosensitive receptors are absent.positive scotoma one which appears as a dark spot in the visual field.relative scotoma an area of the visual field in which perception of light is only diminished, or loss is restricted to light of certain wavelengths.ring scotoma annular s.scintillating scotoma blurring of vision with the sensation of a luminous appearance before the eyes, with a zigzag, wall-like outline; called also teichopsia.ring sco·to·maan anular area of blindness in the visual field surrounding the fixation point in pigmentary degeneration of the retina and in glaucoma.ring sco·to·ma (ring skō-tō'mă) An anular area of blindness in the visual field surrounding the fixation point in pigmentary degeneration of the retina and in glaucoma. scotomaS04-843480 (sko-to'ma) plural.scotomata [Gr. skotoma, to darken] An island-like blind spot in the visual field.absolute scotomaAn area in the visual field in which there is absolute blindness.annular scotomaA scotomatous zone that encircles the point of fixation like a ring, not always completely closed but leaving the fixation point intact. Synonym: ring scotomaarcuate scotomaAn arc-shaped scotoma near the blind spot of the eye. It is caused by a nerve bundle defect on the temporal side of the optic disk. central scotomaAn area of depressed vision involving the point of fixation, seen in lesions of the macula.centrocecal scotomaA defect in vision that is oval-shaped and includes the fixation point and the blind spot of the eye.color scotomaColor blindness in a limited portion of the visual field.eclipse scotomaAn area of blindness in the visual field caused by looking directly at a solar eclipse.flittering scotomaScintillating scotoma.negative scotomaA scotoma not perceptible by the patient.peripheral scotomaA defect in vision removed from the point of fixation of the vision.physiological scotomaA blind spot caused by an absence of rods and cones where the optic nerve enters the retina.positive scotomaAn area in the visual field that is perceived by the patient as a dark spot.relative scotomaA scotoma that causes the perception of an object to be impaired but not completely lost.ring scotomaAnnular scotoma.scintillating scotomaAn irregular outline around a luminous patch in the visual field that occurs following mental or physical labor, eyestrain, or during a migraine. |