Ophthalmology & Optometry/presciption difference


My contact prescription is OS -10.00(toric) and OD -0.75(regular).  My glasses prescription is OS -13.00 and OD -0.75.  Is it unusual to have such a large power difference -10 to -13? This is the first time with a toric in the "bad" eye.  I didnt' know if the toric was the difference. I just had my prescriptions finalized and was wondering before ordering contacts and glasses.  Thank you for your time.

Hi Jackie,
Some of your information is incomplete.  But if your question is my glasses have a -13 and my contacts a -10 somewhere in the Rx, yes this could me normal.  Because the contacts are right on the eye, and glasses fit off the eye, the prescription power in the contacts is usually equal to or lower than the glasses.  
I hope this helps,
Dr. Mike

Ophthalmology & Optometry

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Michael J. Wojciak, O.D.


I am an Optometrist with 25 yrs experience. I currently practice in Rolling Meadows, Illinois. I specialize in all types of contact lenses. Please forward appropriate questions pertaining to eye exams, glasses or contact lenses only. I will always attempt to be as "specific" as I can on my answers. This is often difficult when the questions do not provide enough information or visual presentation is needed. ***I will reject any question involving self-prescribing of contact lenses or involving contact lens measurements/comparisons (such as changing base curves, measurement comparisons between brands etc). Contact lenses are a medical device and need to be properly fit by your Doctor. Also in respect for patient privacy, I will not answer third party questions, unless a parent or guardian is asking a question about their child.*** I appreciate your confidence.


Education/Credentials: B.S. Biology/Pre-Professional Studies, University Of Notre Dame, 1982. B.S.V.S. Visual Science, Illinois College Of Optometry, 1984. Doctor Of Optometry, Illinois College Of Optometry, 1986. Therapeutic Certification, Illinois College Of Optometry, 1996.

Illinois College Of Optometry University Of Notre Dame

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