Medically reviewed by Johnstone M. Kim, MD Mydriasis occurs when the pupil remains dilated (widened) and doesn't respond to light changes in an environment. It can happen due to an injury, medications ...

Medically reviewed by Bryan M. Wolynski, OD Dilated pupils (mydriasis or fixed pupils) are when your eyes' pupils, which let light into your eyes, become wider. This can happen due to medications used ...