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Date of last update: 10/04/2017.

Forum Name: Neurology Topics

Question: Unilateral Headaches and Anisocoria

 Maureen11 - Mon Jan 26, 2009 4:19 pm

Hello, I am a 33 y/o femaIe, no major health issues. I have been suffering from right sided headaches for over 14 years. They seem to come and stay for weeks at a time, with pain free intervals of months. I have been to countless doctors, tried countless meds, and the headaches don't respond to anything. There is no real pattern to them...I have no family history of migraines and did not suffer from headaches when I was younger. I was in 2 car accidents when I was 18 and suffered concussions(not sure if thats relevant). Around 7 years ago(2002) I noticed my right (same side as headaches) pupil was larger than my left but still responded properly to light. This scared me so I saw a neuro who sent me for an MRI/MRA which was normal. The headaches came and went as always through the years and I had a repeat MRI/MRA in 10/2006, also normal. I am currently 3 months pregnant and my headaches have returned. I try not to worry about them but lately I find myself constantly checking my larger pupil and reading about sinister causes of anisocoria and headaches online. Both pupils respond to light and there is no difference in the anisocoria in dim/bright light. The difference is less than 2mm in size. I have read that MRI/MRA does not always pick up aneurysms. Do I have reason to worry?
Thanks so much in advance,
 John Kenyon, CNA - Sun Feb 08, 2009 11:20 pm

User avatar Hi Maureen -

While I don't think you have any reason to worry, you do have reason for a healthy concern, since you have several significant neurological symptoms (of long duration, which is why I don't feel they warrant as much worry as concern). The headaches and even the pupil dilation may well be connected to the concussions you suffered, since the headaches began not too long after that happened. This could have caused some sort of obscure injury which has caused the long-term chronic problems which are now flaring again due to hormonal changes related to pregnancy.

While MRI/MRA will pick up most abnormalities, it is possible to miss an aneurysm or, more likely, an arteriovenous malformation, which could have been present pre-concussion but may have been disturbed in some way by the trauma.

There are other, more sophisticated and complex brain imaging techniques which are aimed at visualizing specifically this type of abnormality, and if you don't currently have an (interested) neurologist, I'd suggest a consult with one now, to avoid any possible late-pregnancy or delivery problems for you, since one of the inevitable things that happen during labor is increased intracrania pressure (which could test a weakness that might exist).

I hope this is helpful to you. Best o fluck to you. Please follow up with us as necessary.
 Maureen11 - Fri Feb 20, 2009 3:46 pm

Thank you so much for your reply John. I have since seen another neurologist who does not seem very concerned, as you said, given the duration of my symptoms. He also said the size of the pupils is not as important as the fact that they react to light properly, which they both do, and I have an otherwise normal neurological exam. He was comfortable with my past mri/mra results seeing as I had 2 of them, 4 years apart and neither showed anything, and my headaches have not worsened. I felt reassured for a few days until I came home and started googling and coming across scary results. Do you agree with the doctors assessment? Just curious what your opinion is...Thank you again and take care. Maureen
 John Kenyon, CNA - Sat Feb 21, 2009 2:16 pm

User avatar Hi Maureen,

I'm really glad you had a second neuro consult. Given the result of that evaluation I feel even more confident and would concur with the opinion of the second doctor for sure. The main thing that makes it all look promising is the stability of symptoms. There is nothing progressive going on, so you're probably just one of those "lucky" people who winds up with symptoms that don't really mean much beyond the distraction they cause. Everything else does seem to be in order, and you've taken the very prudent and appropriate step of getting an informed second opinion. I think you're going to do fine.

Please keep in touch and update us if anything should change. Take care. My best to you.

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