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Related to aniseikonia: anisophoria


A condition in which the shape and size of the ocular image differ in each eye.

[From anis(o)- + Greek eikōn, image.]

an·i′sei·kon′ic (-kŏn′ĭk) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Medicine) a condition caused by a defect in the lens of the eye in which the images produced in the two eyes differ in size or shape
[C20: New Latin, from aniso- + Greek eikon image]
ˌaniseiˈkonic adj
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˌæn ə saɪˈkoʊ ni ə)

a defect of vision in which the images at the retinas are unequal in size.
[1930–35; anis (o)- + Greek eikṓn image, icon + -ia]
an`is•ei•kon′ic (-ˈkɒn ɪk) adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.

aniseikonia, anisoconia

a defect of the eyesight in which the images on the retinas are different in size. — aniseikonic, adj.
See also: Eyes
-Ologies & -Isms. Copyright 2008 The Gale Group, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.aniseikonia - visual defect in which the shape and size of an ocular image differ in the two eyesaniseikonia - visual defect in which the shape and size of an ocular image differ in the two eyes
vision defect, visual defect, visual disorder, visual impairment - impairment of the sense of sight
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
In patients with diplopia as a result of anisometropia, contact lenses can reduce the impact of aniseikonia and differential prismatic effects, helping to enable fusion.
On the other hand, the evolution of the disease tends to be asymmetric, and even in the presence of regular astigmatism, the correction with glasses may result in aniseikonia due to the induced refractive anisometropia.
* Aniseikonia. A condition in which the image seen by one eye differs in size and shape from that seen by the other, aniseikonia doesn't need to be referred unless the difference is greater than 2 mm, which suggests underlying pathology.
(14) Large differences in refractive error that are corrected by spectacles may result in diplopia due to unequal image sizes arriving at the visual cortex (aniseikonia); (15) contact lenses are a good solution in these cases.
For instance, very high myopia in an unoperated eye may require correction and the patient may experience discomfort due to aniseikonia. However, mild to moderate myopia (e.g., -1D) may help intermediate vision and eliminate the need for spectacles [20].
There are two main concerns that need to be addressed when dispensing anisometropic prescriptions: differential prismatic effect; and possible size differences in resultant retinal images, that is to say, aniseikonia. Firstly, prismatic effect issues will be considered, illustrated by a single vision case study to show how even these lenses require anisometropic consideration.
The use of contact lenses can also be very beneficial for patients with anisometropia--both axial and refractive--and its resulting aniseikonia. In these situations, spectacle correction results in the retinal images presented to each eye being different in size resulting in difficulty fusing the cortical images.
(5) Driving with the implant is considered a contraindication due to aniseikonia. The image of the implanted eye will be 3x larger than that of the fellow eye causing difficulty with depth perception.
Some younger patients are reluctant to wear spectacles, especially if they are anisometropic and have functional vision in one eye, as the aniseikonia induced by spectacle magnification can be an uncomfortable visual challenge.
The right eye was fitted with an extended wear contact lens to provide the best vision by eliminating the effects of anisometropia and aniseikonia. A spectacle dispense was required for when the contact lens could not be worn.