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Unequal pupil sizes
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Unequal pupil sizes

  Dear Doctor
  Thank you in advance for your time! My question is what would make my right pupil slightly larger than my left one? I do not have any eye pain or loss of vision. I have noticed that when light is shone in my eyes my pupil reacts to light just like the other one. An eye doctor I saw a few years ago mentioned a .5 cupped disc? Could this be the reason? I have seen a neurologist for headaches and CT scans were negative however a MRI with and without contrast picked up an area of a small bleed in my head most likey due to traumatic injury as I was invilved in a car accident with a blow to my head. No other signifigant findings were found with the scans and otherwise I am neurologically intact as he stated. I smoke 1/2 pack of cigarettes daily and I do not consume any alcohol. Any information you can provide me with is greatly appreciated. Thank you very much!
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There are several things which can cause a difference in pupil size.  Most of these are "physiologic" which means they are varients of normal.  This is usually the case if the difference in size between the two pupils is less than 1 mm.  Nothing needs to be done in this case.
If one pupil is much larger than the other and does not react when light is shone in, this could be a nerve problem which requires urgent evaluation.  Other causes include poor dilation due to a nerve problem (Horner's syndrome).  Trauma to the eye can affect the ability of the pupil to constrict and cause different pupil sizes.  There are also some rare causes such as Aides pupil.
Since your condition has been stable for a while, I doubt there is a problem.  The optic nerve cup should have no relationship to the pupil size.
If you have not had a complete eye examination by an ophthalmologist or if you have noticed any change in your pupils, you should see an ophthalmologist.
This information is provided for educational purposes only.  Please consult your physician for diagnostic and treatment options.

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