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Dr. Rick
Dr. Rick, Board Certified MD
Category: Eye
Satisfied Customers: 11267
Experience:  Ophthalmology since 1994 with Retina sub-specialty interest
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I recently noticed that my right pupil gets larger then the

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I recently noticed that my right pupil gets larger then the left pupil. They both constrict and dialate normally. When I am ouside in the light they are both small as usual however when I am indoors and I look in the mirror I notice that the right pupil wil get slightly larger then the left. Sometimes this happens and sometimes they are the same. I posted this question in the neurology section and the Neurologist scared the hell out of me becuase they thought based on my description that I possibly had Horners Syndrome. Thank goodness I looked it up becuase Horners deals with one pupil constricting and never dialating. Dr's make a diagnosis of Horners by applying drops to the contricted pupil and if it doesnt dialate then they diagnose Horners. I have been to two Opthamologists in the past two weeks and both did full exams on me. Checked eye pressure, looked at the nerves and everything. They both said everything looked completely normal. The CT of the nerves were great and normal pressure on both eyes. I guess I am trying to get a third opinion on this. Is this something I should be worried about like a brain tumor? Can you put me at ease? If something would have been wrong like a brain tumor wouldn't of something showed up in one of the tests they gave me? I also had a MRI in January of this year and everything came back normal. Is this something I should be worried about? The Neurologist realized after I told them both pupils dialate and constrict fine that Horners Syndrome was not possible.  Your thoughts?
Submitted: 5 years ago.
Category: Eye
Expert:  Dr. Rick replied 5 years ago.

Dr. Rick :

Hi. I'm online and happy to answer your question today.

Dr. Rick :

Everyone thinks brain tumor first :) You, from what you have told me, don't have one.

Dr. Rick :

The number one cause for your problem is physiologic anisocoria. Sure there are a lot of pathological things that can cause differences in pupil size but I feel very confident in saying that after two complete eye examinations by ophthalmologists, imaging of your nerves and an MRI you are just fine.

Dr. Rick :

Do not worry. Ok? Ok. You are fine.

Dr. Rick :

Does this make sense to you?

Dr. Rick :

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Dr. Rick :


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Expert:  Dr. Rick replied 5 years ago.
Let me know if there are there any other concerns or issues you would like to discuss on this topic.
Customer: replied 5 years ago.
Is anascoria life threatening? Could it be caused by something Neuro disease like ALS or MS or even cause those later on?
Expert:  Dr. Rick replied 5 years ago.
No. It's just a fancy work for unequal pupil sizes. If we doctors used everyday words no one would pay us for our wonderful "knowledge" lol!

Here is a good webpage on the topic:

Ignore all the bad stuff. You have a normal variation in pupil size. Nothing to worry about.

It is now safe to press the "yes" button if you like. And the good news? I don't go up in a puff of smoke when you do that an I will still be here to answer more questions on this topic if you would like.
Customer: replied 5 years ago.

I am worried about physiologic anisocoria. Should I get another MRI since my last one was about 10 months ago or should things stil be the same? Could something bad have developed in that amount of time? Why would this have started to happen all of a sudden out of nowhere? Does physiologic anisocoria just come on suddenly like that?

Expert:  Dr. Rick replied 5 years ago.
There is nothing to worry about. It is a normal finding. That is what physiologic means. Your heart beat is physiologic.....

Yes, it can come on suddenly for no apparent reason. I have had it myself and notice in my daughter when she was about 3 years old...and now she is 29 and asking me to kick and help her with a new car. So. See? You have nothing to worry about but worry itself. (I think Winston Churchill said something like that during WWII :)
Expert:  Dr. Rick replied 5 years ago.
Dr. Rick and other Eye Specialists are ready to help you
Customer: replied 5 years ago.
Thankd Dr.