MedlinePlus Medical Encyclopedia: Iris

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Iris

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Illustrations	Definition

Illustrations

Iris

Definition Return to top

The iris is the colored portion of the eye located between the cornea and lens. The iris' round, central opening (the pupil) contracts and dilates to control the entrance of light into the eye.

Update Date: 8/17/2007

Updated by: Manju Subramanian, MD, Assistant Professor in Ophthalmology, Vitreoretinal Disease and Surgery, Boston University Eye Associates, Boston, MA. Review provided by VeriMed Healthcare Network.

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