| refractive amblyopia | A suppression of central vision due to an unequal refractive error (anisometropia) of at least two diopters. This induces a sufficient difference in image size (aniseikonia) that the two images cannot be fused. In order to avoid confusion, the blurrier image is suppressed. Synonym: refractive amblyopia. (05 Mar 2000) |
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| refractive | Serving or having power to refract, or turn from a direct course; pertaining to refraction; as, refractive surfaces; refractive powers. Refractive index. <medicine> The ratio of the sine of the angle of incidence to the sine of the angle of refraction for a ray passing out of one of the media into the other. Origin: Cf. F. Refractif. See Refract. Source: Websters Dictionary (01 Mar 1998) |
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| refractive accommodative esotropia | That type of esotropia eliminated by correction of hypermetropic refractive error. (05 Mar 2000) |
| refractive errors | Deviations from the average or standard indices of refraction of the eye through its dioptric or refractive apparatus. (12 Dec 1998) |
| refractive index | <microscopy> The ratio of the velocity of light in a vacuum to the velocity in some medium. Refractive index generally increases with the atomic number of the constituent atoms. (05 Aug 1998) |
| refractive keratoplasty | Any procedure in which the shape of the cornea is modified, with the intent of changing the refractive error of the eye; for example, if the cornea is flattened, the eye becomes less myopic. See: photorefractive keratectomy, keratophakia, lamellar keratoplasty, thermokeratoplasty, keratomileusis, radial keratotomy. Synonym: keratorefractive surgery. (05 Mar 2000) |
| refractive keratotomy | Modification of corneal curvature by means of corneal incisions to minimise hyperopia, myopia, or astigmatism.In this type of radial keratotomy surgery, performed by excimer laser, pie-shaped pieces of cornea are removed under local anaesthetic. The resulting scar tissue formation reshapes the cornea. This class of surgery is somewhat unpredictable, and its long-term effects are still unknown. (05 Mar 2000) |
| amblyopia | <ophthalmology> The impairment of vision without detectable organic lesion of the eye. (18 Nov 1997) |
| amblyopia ex anopsia | The suppression of the central vision in one eye when the images from the two eyes are so different that they cannot be fused into one. This may be due to: 1) faulty image formation (sensory amblyopia); 2) a large difference in refraction between the two eyes (anisometropic amblyopia); or 3) the two eyes pointing in different directions (strabismic amblyopia). Most suppression amblyopia can be reversed if appropriately treated before age 6 years. Synonym: amblyopia ex anopsia. (05 Mar 2000) |
| anisometropic amblyopia | A suppression of central vision due to an unequal refractive error (anisometropia) of at least two diopters. This induces a sufficient difference in image size (aniseikonia) that the two images cannot be fused. In order to avoid confusion, the blurrier image is suppressed. Synonym: refractive amblyopia. (05 Mar 2000) |
| sensory amblyopia | A suppression of central vision in one eye due to faulty image formation; for example, by a corneal scar, a cataract, or a droopy eyelid. Synonym: deprivation amblyopia. (05 Mar 2000) |
| hysterical amblyopia | An apparent loss of visual acuity or visual field with no substantiating physical signs; often due to a natural concern about visual loss combined with suggestibility and a fear of the worst; best treated with reassurance. (05 Mar 2000) |
| strabismic amblyopia | A suppression of central vision due to the two eyes pointing in different directions. The two scenes cannot be fused into a single image, so, to avoid confusion, one of the images is suppressed. (05 Mar 2000) |
| nocturnal amblyopia | Night blindness or difficulty in seeing at night. Symptom of vitamin A deficiency. (27 Sep 1997) |
| nutritional amblyopia | Amblyopia resulting from lack of vitamin B-complex constituents. (05 Mar 2000) |
| suppression amblyopia | The suppression of the central vision in one eye when the images from the two eyes are so different that they cannot be fused into one. This may be due to: 1) faulty image formation (sensory amblyopia); 2) a large difference in refraction between the two eyes (anisometropic amblyopia); or 3) the two eyes pointing in different directions (strabismic amblyopia). Most suppression amblyopia can be reversed if appropriately treated before age 6 years. Synonym: amblyopia ex anopsia. (05 Mar 2000) |