Ophthalmology & Optometry/slab off


Hi, In previous optometric examinations I have had to get a slab off prescription.  Because this makes purchasing glasses a very expensive option, I tend to neglect getting regular examinations.  Are there any alternatives to the slab off choice.  Is it really a necessary option for some prescriptions?  Do some people absolutely need this?  I'm sorry that I cannot tell you what my prescription is.  I am a 67 years of age and also need tri-focals, which adds to the expense.  Thank you

Hi Karen,
Slaboff is simply prism added or removed from the bottom of a lens in order to prevent seeing double when looking through the bottom of the lenses using both eyes together.  If the two eyes have a significantly different Rx, without slaboff you may see double when looking through through the 'non-central' areas of the lenses.  You may or may not see double, so you could try without slaboff and see if you see double or adapt to it and your eyes may not see double.   Or get single vision for near or intermediate or distance glasses no bi,tri focal and then you just look through the center and no double. No harm in trying, and you may succeed without slaboff but it may take a while for your eyes to recalibrate and coordinate.
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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