Changes in Iris & Pupil Appearance

Certain conditions and factors can affect the shape, size and appearance of the eye’s iris and pupil. Explore common changes in these structures and how they may impact vision and eye health.

MORE TOPICS

What Makes One Pupil Bigger Than the Other? (Anisocoria)

Anisocoria (unequal pupil sizes) can be harmless, but it can also signal a serious medical issue. Learn about its causes and when to seek medical care.

Coloboma: What It Is & How It Affects Your Eyes

Learn about coloboma, a condition that causes missing tissue in different eye structures. Find out how it affects vision and how to manage its effects.

Mydriasis: Definition, Causes, Treatment

Learn about mydriasis, a dilated pupil that is unresponsive to light. Discover medications, injuries and conditions that cause it and learn how to treat it.

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