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A 21-year-old female asked about a 19-year-old female:

Sisters pupil reacts to light but instantly returns to original (large) size even while light remains on eye? is this normal?

1 doctor answer5 doctors weighed in
Dr. Daniel Schainholz
Ophthalmology 35 years experience
Swinging flashlight : Testing for an afferent pupillary defect, a so-called marcus-gunn pupil, is performed with the swinging flashlight test. The comparison made is between the direct and consensual responses. When the consensual response exceeds the direct response, an optic nerve or retinal problem may be inferred. Your description may be of hippus, a benign tonal oscillation of the iris musculature. See an eye md.
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Last updated Jan 10, 2015

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