unequal pupil dilation

Hello there.  My question comes on behalf of my younger brother, who recently sustained a head injury that was thought to be a concussion, though no official diagnosis was sought.  About a week has passed since the incident and he has started to complain about minor headaches, a symptom that had him sent to his school nurse yesterday, who noticed a disparity in the size of his pupils as the right one was slightly larger than the left.  After multiple members of our families confirmed the abnormality, we took him to a doctor who promptly tested his eyes for reactivity, among others thing, and declared him to be perfectly fine.  Having worried about the kid all night, this seems like great news but not having been there to hear the doctor myself, some reinsurance would be welcomed.  Is there any chance that he could have a serious problem that could feasibly go unnoticed by a professional?

[SamPCS]

Have you taken a CT scan or MRI?   At this stage an MRI would be better.

Headaches may be due to concussion which is common.  Not sure about the eyes.  Consult a Neurologist and get some scanning done as soon as possible.

"No head injury is too severe to despair of nor too trivial to ignore." Hippocrates, 4th Century, BC

[Dr. Kokil Mathur]

Hi
Welcome to the MedHelp forum!
Unequal pupils but the difference between the two pupils being less than 2mm is physiological variation. If it is more than 2 mm then it could be due to pathologic anisocoria. This is due to an abnormality in the musculature of the iris or in the parasympathetic or sympathetic innervations to the pupil. It is also a sign of serious brain injury. Aneurysms, bleed in the brain, glaucoma, meningitis and tumora also cause unequal pupil size.
There is no harm in getting a CT scan or MRI of the brain done as your brother has persisting headaches. Take care!