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Lincoln, NE
A 60-year-old female asked:

Use progressive lenses and monovision contacts . when i cover one eye objects appear larger in one eye than the other. why is that?

1 doctor answer1 doctor weighed in
Dr. Daniel Schainholz
Ophthalmology 36 years experience
Accidental telescope: The eye with the more minus contact lens sees the larger image because a minus lens acts as an eyepiece in a Galilean telescope, while the progressive bifocals act as the objective lens. This is of theoretical, but little practical value clinically. Either switch to bifocal contact lenses or correct both eyes for distance with the lenses and use over-the counter readers. Aniseikonia fixed.
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Last updated Aug 23, 2014
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