Am Orthopt J 44:50-55 (1994).
Evaluation and Management of Monocular Diplopia
Virginia C. Hansen, C.O.
Monocular diplopia is the double vision that occurs in only one eye and is time consuming to diagnose and treat. The patient is understandably cranky and persistent. But the most common misconception is wrong: they're not crazy!
A literature search revealed something painfully clear. There is scant literature on the subject.
This discussion will cover the different types, how to detect it, and how to get rid of it. Realize that sometimes the detection is the treatment so some aspects of monocular diplopia will be simultaneously reviewed.
© 1994 The Board of Regents of the University of Wisconsin System

Double vision. Usually due to misalignment of the eyes. Monocular diplopia (diplopia when viewing with one eye) is unusual and is most often caused by an abnormality in the cornea or lens, and rarely by a detached retina. Rarely monocular diplopia can be due to a central lesion.
Original Date: Feb 10, 1995
Last Update: Feb 10, 1995

Monocular diplopia usually results from some dysfunction in refraction, most often the lens but potentially involving the cornea or retinal (rare reports of CNS). In the series by Morris, problems with the lens accounted for about 40% of these problems and corneal problems another 25%. No causes was established in slightly more than 10% of cases.
Extra-ocular – problem with corrective lens or contacts
Ocular - corneal abrasion, infection, trauma, keratoconus
Iris – pharmacologic mydriasis
Lens - opacities, cataracts, following lens implant, problems with implant
Retinal – detachment, central retinal venous occlusion, neovascularization
No causes / possible psychogenic

Problems with cranial nerves resulting in diplopia may stem from dysfunction of cranial nerves III, IV, or VI and may be obvious or subtle

Monocular Diplopia: Should suggest corneal or lens problem.

. Other common causes of monocular diplopia include corneal opacity (e.g., corneal ulcer) or swelling (corneal edema) and cataract. Less common but important causes of monocular double vision include cranial nerve palsies, a dislocated intraocular lens implant, orbital fracture, retinal detachment, and myasthenia gravis. Other causes are rare.


Monocular diplopia indicates a problem within the ocular media, particularly the cornea and lens. Monocular diplopia is not neurogenic; it does not involve cranial nerves III, IV and VI.

Diplopia:
Monocular or binocular? True double vision is only binocular. Constant or intermittent? In which direction of gaze?
COMMON CAUSES: Cranial nerve palsy (3,4,6), orbital floor fracture, thyroid eye disease, not child onset
strabismus.