One Dialated Pupil

Updated on December 29, 2007
M.A. asks from Denver, CO
9 answers

My son is almost 3 months old and one pupil is larger than the other. We just noticed it and called the Dr. She is refering us to a Neuro Surgeon. Referals take about a week or two with our particular insurance so I get to sit and worry in the meantime. Does anyone have any experience with this? My internet research has said it can be anything from brain bleeding and swelling, eye cancer or nothing at all. My sister talked to an opthomologist friend who said as long as the pupil changes with light (which it does) it is not an emergency situation. I'm just wondering if there are others out there with two differnt size pupils.

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So What Happened?

Thank you so much for all of your input. I feel much better. I am still of course going to take him to the specialist, but this makes me feel better in the meantime. I'm glad there are others out there.

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answers from Grand Junction on

My daughter has the same thing- as long as it dilates with light- my doctor said it was fine- it is a genetic trait. My doctor's wife has the same trait. When my daughter was 3 mos it was more noticeable, but not much now, she is 8 mos now.

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answers from Tucson on

Hi there~
I hope I can ease your mind a little bit. My middle daughter is 7 and has always had one larger pupil, as do I. She has seen the pediatrician about this and an ophthalmologist as well and the same advice was given. As long as the pupil changes with light it is probably nothing. Of course check it out to be safe but rest easy as it is probably just how he was made. :)



answers from Denver on

Dear M.,

There are many things that can cause one pupil to be larger than
another. However, if this is something that is new, I recommend that you take your infant to an emergency room. If you have
a children's hospital nearby, that would be best as there
will be pediatric specialist on staff that can evaluate your
child. Due to the age of your child, he cannot really offer
complaints, so it is important to have this evaluated sooner
rather than later. If you have insurance that requires
some type of approval for emergency room visits let them know
that this is an acute change and due to your internet
research, you have learned that it is not advisable to wait
2 weeks for an evaluation. Stay calm, but move forward with
this evaluation. Good luck!



answers from Phoenix on

if she had bleeding or swelling of the brain she would already have shown other symptoms. this is not common but i have seen it often in the emergency room. i think you should just wait for the consult and then worry fi it is warranted



answers from Pueblo on

It very well could be iris coloboma of one you have any pictures of the eye you could send me.... both my girls have coloboma so I am fairly familiar...let me know if you have any questions
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answers from Phoenix on

Dear M.,
Please Call your Doctor and validate that it is not to
be concerned or alarmed.
A difference in pupils is also a sign that your baby may have
a head injury. Please check today.




answers from Phoenix on

i JUST went through this with my daughter. i noticed it when she was about three months old (mainly i think b/c she was more alert and wide eyed.) anyway, it is called anasocoria (sp?) and there is nothing actually wrong with the eye or pupil. it happens in about 20% of the population. my daughter has super light blue eyes and so at first i noticed it all of the time, but now it is just a part of who she is. most people never even realize it unless i point it out. and i can barely even tell when it's bright light during the day or when it's pretty dark. the only time it's really noticeable is in dim light like in the evening.
but, i did the same thing you did. search the internet and drive yourself crazy thinking it's a brain tumor or a neurological problem. i can't say for sure until you see the doc, but it's actually more common than i realized. the eye doc that i first went to had the same thing. i just had never heard of it before.
oh, and i put my daughter in all different sorts of lights and both pupils reacted the same every time...the right one is just about 1mm bigger at all times then the left. why are they sending you to a neuro surgeon before first seeing a pediatric opthomologist? oh, and i just looked it up. it's spelled Anisocoria.
i also wanted to tell you that the eye doc just had me watch her eye for any type of drooping (of the eye and face.) we went to the initial appt and then a follow up six weeks later. during the six week checkup, he said he was confident nothing was wrong, b/c he definitely would have seen some changes in her face and eye. so, just keep watching him for any changes. the doc said if it was any type of tumor or growth, he would have seen it when they dialated my daughters eyes and that those types of tumors tend to grow fast. so, since he didn't see anything different at all in the six week check...she's fine. :)



answers from Phoenix on

HI M.,

I am an adult who has had different size pupils all my life.
I have very blue eyes but I have no idea if that has anything to do with it. I have worn glasses since the 5th grade. That's it. Nothing else wrong with me. I am glad that I was aware of my pupil size difference though because it was important to know once when I was in an accident. The paramedics looked at my pupils, checked them for dilation and constriction with a light. They were both responsive but it could have been indicative of another problem if pupil size difference wasn't normal for me. Seems like unless she's having some other symptoms it's not an emergency. Good luck.



answers from Grand Junction on

Hi M.,

My son also had one pupil larger than the other at around three months. I looked on the internet and found all sorts of worst-case scenarios. Very scary. We went to a pediatric opthamologist and measured the diffence in pupil size along with a regular check up. His eyes were fine otherwise. He had a follow up appointment six months later and the pupils were much closer in size. He's just fine! I hear that slight diffentiation in size is not so uncommon.
I hope this helps your worry.

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