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Problems with New Glasses
Atlantis wrote:
I recently got new glasses. The first day I wore them I could only stand to wear them for 8 hours because they made me feel nausea and feel like I was going cross eyed. The cross eye sensation has gone, but the dizziness and nausea continues. Should I give it more time? Could it be due to the PD that they measured in the eyeglass store or is it more likely something to do with my prescription?
Thanks
Dr Henry Smit's response:
Dear Atlantis
The symptoms you describe can be caused by an incorrect PD measurement, an incorrect prescription, a change in lens design (density and curvature) or poorly fitted eye wear. However, these symptoms can occur even when the PD measurement, the prescription and the eye wear fitting etc. is completely accurate. A significant change in prescription can affect the binocular coordination of the eyes because the functions of convergence (turning the eyes inward) and accommodation (focusing the eyes on a close up object) are intricately linked. A significant change in prescription most often alters the amount of accommodation required to see up close, and this temporarily upsets the person’s accommodation/convergence balance until the visual system adjusts to the change.
In my experience, patients can present with a wide range of maladaptive symptoms when adjusting to new eye wear. The identical change in prescription might not induce any negative symptoms in one patient, but cause another patient to go into a bit of a tailspin. I am encouraged by the fact that your symptoms appear to be lessening as you wear the glasses. So long as you continue to experience improvement, I would give it a little more time. You might want to return to where you purchased your eye wear to ensure that your glasses are fitted optimally. However, if after a couple of weeks you are still unable to use the glasses comfortably, I would return to your optometrist to have your prescription rechecked to ensure that it is adequate for your current needs. There are certain health conditions, such as diabetes, that can cause your prescription to fluctuate, even on a day to day basis. If a reassessment of your prescription yields a different result from the original, there may be underlying health issues that need to be addressed. If the prescription determined on retest is consistent with the original result, sometimes your optometrist will be able to prescribe an alternate lens design to which you might adjust more easily.
Best of luck,
Dr. Smit
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Problems with Prescription, Possible Cataract
Dana wrote:
I recently went to the eye doctor, and received a new prescription... it had been a few (8) years since I last visited an eye doctor. When I picked up my new glasses (2 pair) I find my vision is blurry when I cover my right eye, since it is 2 pairs of glasses, and it happens with both pairs, I am worried maybe the optometrist gave me the wrong prescription. My previous prescription (8 years ago) was L -225-100x110 R-275-075x70 - my new prescription is L -400-25x165 and R-400-25x020 is this a normal change? The most recent eye doctor is new to me, and I am beginning to doubt the prescription. Thank you.
Dr Langis Michaud's response:
Dear Dana,
My first comment would be that 8 years is way too long to wait for seeing an eye doctor. Every patient should be seen at the most every 2 years, not only for the vision problems but first and foremost to assess ocular health, which can evolve and change rapidly, without any alarming signs.
The changes you are showing here can be normal or abnormal, depending on your ocular health. I don’t know your age but it is a big factor to consider. If you are over 60, my first impression, with this type of change, is that you are beginning the process of developing cataracts. Cataracts, at the beginning, induce more myopia and changes astigmatism. This is what your prescription is showing. Even if the prescription is increased, sometimes, vision remains blurred because of the cataract. Previously, you could be less aware of this because your vision was already blurred by the prescription that was too low for this eye. With the increase in power, the vision is clearer but not perfect, probably because of a cataract, more evolved, on one side.
The best way to address this issue is to go back to your optometrist and ask your questions. I am quite sure that he will welcome you, will answer your questions and will address your concerns. Taking the time to talk is certainly a good way to start to resolve this problem. Perhaps he can’t do anything because of the cataract, but at this time, the best recommendation would be to consider surgery. Again, your optometrist knows your eyes better than anyone else. Consult him and ask questions.
Good luck,
Dr. Langis Michaud, Optométriste, MSc, FAAO (Dipl)
Associate Professor
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Prescription Was Cut Back
Amanda wrote:
I recently went to an optometrist for the first time in 5 years and she told me my prescription had changed quite drastically; specifically, my astigmatism had grown much worse in both eyes. I previously had OD CYL -2.50 and OS CYL -1.25, but she measured me at OD CYL -4.50 and OS CYL -2.75. However, when she was writing out my prescription she told me that that was too drastic a change and gave me a prescription for OD CYL -3.50 and OS CYL -2.00 and told me to come back in a year for another prescription update.
Why can't I get the full prescription now? Due to the severity of my nearsightedness (-10.25) and this astigmatism my lenses are quite expensive. I'd rather just by one pair and maybe take a little longer to get used to them than have to buy two pairs of lenses in two years.
Dr Carol Doman's response:
Cutting back the glasses prescription when there is a big change is quite common. The problem with giving the full prescription is that it could be very hard for you to get used to it. It could take longer than a month to adjust and you may have severe headaches. Not something that most people are willing to tolerate. In your case specific reasons that would make it hard to adjust to the new prescription is the amount of time you’ve had your old prescription and the type of prescription that you have. The longer you have had your current prescription the harder it is to adjust to a new prescription. As well astigmatism (cyl) correction is the hardest type of prescription change to get used to. The amount that they are cutting it back by likely won’t affect your vision significantly. I would have done the same thing that your optometrist is suggesting.
Dr. Doman
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