Coloboma of the iris

Definition

Coloboma of the iris is a hole or defect of the iris of the eye. Most colobomas are present since birth (congenital).

Considerations

Coloboma of the iris can look like a second pupil or a black notch at the edge of the pupil. This gives the pupil an irregular shape. It can also appear as a split in the iris from the pupil to the edge of the iris.

A small coloboma (especially if it is not attached to the pupil) may allow a second image to focus on the back of the eye. This may cause:

If it is congenital, the defect may include the retina, choroid, or optic nerve.

Most colobomas are diagnosed at birth or shortly afterward.

Causes

Coloboma can occur due to:

Most cases of coloboma have no known cause and are not related to other abnormalities. Some are due to a specific genetic defect. A small number of people with coloboma have other inherited developmental problems.

When to Contact a Medical Professional

Contact your health care provider if:

In addition to your child, you may also need to see an eye specialist (ophthalmologist).

What to Expect at Your Office Visit

Your provider will take a medical history and do an exam.

Since the problem is most often diagnosed in infants, knowing about the family history is very important.

The provider will do a detailed eye exam that includes looking into the back of the eye while the eye is dilated. An MRI of the brain, eyes, and connecting nerves may be done if other problems are suspected.


Review Date: 12/2/2017
Reviewed By: Franklin W. Lusby, MD, ophthalmologist, Lusby Vision Institute, La Jolla, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

This information should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. © 1997- 2007 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.