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  • If my vision fluctuates throughout the day, when is the best time to test vision with my ophthalmologist?


    Question:

    I have myopia and I don't wear glasses. I have noticed that my eyesight fluctuates sometimes. I have blurry vision after exercise and after long hours of using a computer. I checked my blood sugar and found it to be normal. Can you tell me what time of the day is best for testing my vision at the doctor?


    Answer:

    I wish you included your age and other pertinent medical history as the answer to your question can be complex and dependent on many factors. There are many causes of mild fluctuation of vision throughout a day. If a person is tired, as after vigorous exercise, their eyelids may droop and give them the effect of squinting which could modify the glasses prescription needed. Around the age of 40, most people begin to develop presbyopia (need for reading glasses). Some can get away without reading glasses by force-focusing. This can cause the focusing muscle inside the eye to go into spasm and thus create blurry vision after reading for extended periods of time. It can also happen with distance vision as in watching an extended amount of TV at the same distance from the screen. You might explain your observation to your ophthalmologist and ask that the eyeglasses measurement be taken at two different times of the day, making sure no dilating drops are put in your eyes for many hours before the second reading, as in two different days.


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