Ophthalmology & Optometry/prism and seg


Hello, my present glasses progressives with a 3 diopter prism/eye. I need to get a pair of computer glasses, and I wonder if the prism I wear will affect a bifocal seg. These are strictly for work, and will be 5 diopters per eye and he suggested a bifocal for reading close and the computer which is about 20" away. Any other consideration I need to think about?

History...I am 53, and have diplopia due to a car accident 25 years ago in which I hit the back of my head. At the time my eyesight was fine, and I did not wear glasses. My uncle was an opthalmologist, and after the accident he gave me glasses with a press-on prism to the left lens. After a year the diplopia cleared so that it was only evident in the very top of my gaze, and for the next 22 years all was well. At mid 40's my near vision blurred and my muscles slipped so I now wear prisms all the time. Thank you! L

Hi Liz,
This type of prescription should be exactly determined and prescribed by your doctor. Using your required self measured and exact viewing distance and direction of gaze, the amount of prism and glasses power will be determined, often with trial frame and testing. I would not guesstimate or generalize at all.
Mitch Axelrod, OD

Ophthalmology & Optometry

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Mitchell Axelrod


I'm happy to answer questions about eye exam findings and procedures, glasses and contact lens types/prescriptions/problems. I can also answer questions about general eye conditions/diseases. I do not answer questions concerning surgical techniques/procedures. Please state your age or within a small range when asking questions, as it is often important.


Optometrist 19 yrs.

Doctor of Optometry, cum laude; Residency in Ocular Disease

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