9 doctors weighed in:

During a stroke or brain aneurysm, will the pupils be dilated and fixed or just dilated? Are neither of the two normal?

9 doctors weighed in
Dr. Clemens Schirmer
Radiology - Interventional
7 doctors agree

In brief: Depends

A specific aneurysm location in the brain can cause dilation of one pupil alone which may occur in a patient who otherwise does not have any other specific problems.
In general dilation and lack of reaction to light (=fixed) of one or both pupils indicates brain swelling and pressure of the brain on the 3rd cranial nerves which is an emergency and can be an sign of brain death if left untreated.

In brief: Depends

A specific aneurysm location in the brain can cause dilation of one pupil alone which may occur in a patient who otherwise does not have any other specific problems.
In general dilation and lack of reaction to light (=fixed) of one or both pupils indicates brain swelling and pressure of the brain on the 3rd cranial nerves which is an emergency and can be an sign of brain death if left untreated.
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Dr. Abhineet Chowdhary
Neurosurgery
1 doctor agrees

In brief: Unclear

Pupil response is based on many factors.
If there is an increase in intracranial pressure, this can cause a change in the pupils. This can be a sign of impending "herniation" which can be catastrophic.

In brief: Unclear

Pupil response is based on many factors.
If there is an increase in intracranial pressure, this can cause a change in the pupils. This can be a sign of impending "herniation" which can be catastrophic.
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