Aniseikonia

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Article initiated by:

Ayesha Shariff, MSIV, Robert F. Melendez, MD, MBA

All contributors:

Robert F. Melendez, MD, MBA, K. David Epley, M.D., Vandana Reddy, MD, Brian Shafer, MD

Assigned editor:

Brian Shafer, MD

Review:

Assigned status Update Pending

 by Brian Shafer, MD on October 20, 2021.

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Contributing Editors:	add

Aniseikonia

DiseasesDB

29646

ICD-10

H52.3

MeSH

D000839

Aniseikonia is the difference in image size perceived between the eyes from unequal magnification. The two most common causes are anisometropia and retinal pathology. Symptoms of aniseikonia include diplopia, headache, dizziness, disorientation, and excessive eye strain.

Disease Entity

Disease

Aniseikonia is the difference in image size perceived between the eyes from unequal magnification. When the magnification variance between the two eyes is disproportionately high, symptoms can arise.

Etiology

Aniseikonia typically occurs due to either anisometropia or macular pathology. Up to 7% of aniseikonia between the eyes is usually tolerated.

• Anisometropia Aniseikonia: When there is greater than 3D of anisometropia, aniseikonia can occur. This may occur naturally due to antimetropia (one eye hyperopic and the other myopic), aphakia, or simple anisometropia.
• Retinal Aniseikonia: Macular pathology such as cystoid macular edema, macular pucker, epiretinal membrane, macular schisis, central serous chorioretionopathy, macular holes, and other anatomical abnormalities can lead to compression, stretching, or damage to the retina. This will cause light projected on the retina by a perceived image to appear larger (macropsia) or smaller (micropsia), as a variable number of photoreceptors may be stimulated.

Symptoms

Aniseikonia can induce diplopia, headaches, dizziness, disorientation, eye strain, suppression, and balance disorders. The diplopia caused by aniseikonia is not relieved with prisms therapy.

Management

Treatment varies based on the cause of aniseikonia. When it is due to anisometropia, treatment is with glasses, contact lenses, corneal refractive surgery, or lens-based refractive surgery. When due to retinal pathology, magnification size-matched lenses known as isokonic lenses can be used.

Additional Resources

• Porter D, Repka MX. Aphakia. American Academy of Ophthalmology. EyeSmart^® Eye health. https://www.aao.org/eye-health/diseases/aphakia. Accessed November 17, 2022.
• Porter D, Turbert D. Eyestrain (Symptom). American Academy of Ophthalmology. EyeSmart^® Eye health. https://www.aao.org/eye-health/symptoms/eyestrain. Accessed November 17, 2022.
• Vimont C, Barber LG. Eyestrain (Condition). American Academy of Ophthalmology. EyeSmart^® Eye health. https://www.aao.org/eye-health/diseases/eye-strain-list. Accessed November 17, 2022.

References

1. Gerstenblith, Adam T., and Michael P. Rabinowitz. The Wills Eye Manual: Office and Emergency Room Diagnosis and Treatment of Eye Disease. Philadelphia: Wolters Kluwer/Lippincott Williams & Wilkins, 2012. Print.
2. Trattler, Bill, Peter K. Kaiser, and Neil J. Friedman. "Chapter 1: Optics." Review of Ophthalmology. Edinburgh: Saunders Elsevier, 2012. Print.
3. Ugarte M, Williamson TH. Aniseikonia associated with epiretinal membranes. Br J Ophthalmol. 2005; 89:1576-80