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A 31-year-old female asked:

In dim light one pupil does get quite as big as the other unless it's really dark then they look the same.in daylight they are the same, responds normally to light. had full eye exam all normal. dr didn't see it but said 25%of people have this?cause?

1 doctor answer1 doctor weighed in
Dr. Cornelius Oleary
A Verified Doctoranswered
Urgent Care 20 years experience
Anisocoria: Anisocoria is defined as a difference in size between two pupils. The parasympathetic NS constricts the pupil and the sympathetic NS dilates the pupils. Along their respective anatomic pathways from the brain different life threatening conditions such as aortic dissection aneurysms or tumors can cause imbalance, as can trauma. However, majority of times the slight imbalance and asymmetry is benign

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Last updated Oct 3, 2019


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