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URL of this page: //medlineplus.gov/ency/imagepages/9482.htm

Iris

Iris

Overview

The iris is the colored portion of the eye, amembrane located between the cornea and lens that regulates the entrance of light into the eye by contracting and dilating.

Review Date 10/13/2023

Updated by: Linda J. Vorvick, MD, Clinical Professor, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.