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Enlarged pupil in one eye
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Enlarged pupil in one eye


I've recently noticed that one of my pupils (that of my right eye) is at times larger than the pupil in my left eye.  I've had 'issues' with this eye for approximately 5 years, whereby I see flashes of white light in the peripheral some days its all the time other days its non existent.  I've seen my doctor about this and I've had a full examination of the eye (albeit a few years ago now) and there was nothing untoward, I've also had an MRI scan of the brain to check there is nothing the matter here either and thankfully it came back clear (that was mid 2005).  

You can see a very slight difference in the size of the pupil when in a brightly lit room, but it is most noticable when you are in a dimly lit or dark room.  I would say it is approximately 2-3mm larger than the other eye.  The eye does react to a change in light also, so it seems normal but there is just a significant difference in the size of the pupils.

I was happy to just 'plod along' as I was until I've noticed this change in my pupil.  I cannot say when it's changed but I first noticed it a couple of weeks ago.  I am a worrier so this is playing on my mind alot at the moment any suggestions would be appreciated.

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The possibilities here include physiologic anisocoria, Horner's syndrome, adies tonic pupil and third nerve palsy.  Sometimes it is difficult to know which pupil is abnormal the larger one or the smaller one. You should look for associated symtoms (symptoms) especially a droopy eyelid or double vision and an eye that doesn't move properly.  If there is a droopy eyelid and larger pupil or eye turned out - that can be a very serious sign of a possible third nerve palsy - very serious condition.  In your situation, physiologic anisocoria could be tops on the list because you didn't mention a droopy lid, you mentioned that larger pupil is the abnormal one, worse in dim light and no double vision and pupils nearly equal in regular light.  I cannot make your diagnosis without examining you - so you need to see a neuro-ophthalmologist the get the correct diagnosis - which shouln't be too difficult.  Good Luck.

I have dysautonomia but also the left pupil has been larger with a dropy lid since I had the onset of it at age 16 with my galla of symptoms neurologists opthalmalogists pcp psychiatrists all said anxiety. hmmm then lucked out and failed tilt table so it was POTS but this still leaves me with the very slightly droopy lid and larger pupil I also have dimmed peripheral vision most of the time and a hard time focusing from distance to near but I think my contacts get dry or move or something.  I see floaters, and sometimes get like little tiny white flecks that move in all directions if I sneeze or strain, senstivity to light, used to have auras (told it was atypical migraine but i dont know). I guess my vision just always seems like I am overstimulated i focus in on every little detail there is and that makes me worry why.  But also with the near syncope all the time and the brain fog and I also have high pulse rate with little movement shortness of breath and dizzy dimmed peripheral vision objects remain in my vision for a bit after looking at them too.  the opthalmologist suggested it was sleep apnea (which I dd have at my heaviest then after gastric bypass dont) but said that and chronic dry eye did the droopy thing and stenosis of the cervical spine did pupil but what is the 3rd nerve palsy and could I have this? would it show on an mri of brain? thanks Im frantic!  btw im on zoloft lyrica prevacid toprol all bid & ativan prn
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