Abnormal binocular vision: monocular diplopia of physical origin: two case reports. Its relationship to the physiology and arrangement of the visual directions of the retinal areas; binocular triplopia.

Background and purpose: Monocular diplopia is an infrequent but disabling complication following laser peripheral iridotomy, or following cataract surgery. Our purpose is to clarify the intraocular mechanism of monocular diplopia (and binocular triplopia) of physical origin and its relation to the physiology and arrangement of the visual directions of the retinal areas in each eye.

Case reports: This is a report of one patient who developed monocular diplopia following an "exposed" laser peripheral iridotomy, and of a second patient who developed monocular diplopia due to a swollen opacified central posterior capsule following cataract surgery.

Conclusion: Monocular diplopia of physical origin results from stimulation, by an object of regard, of two separate retinal areas that have two different visual directions due to optical ocular pathology.