OverviewA coloboma is a defect in the iris of the eye. It can appear as a black notch of varying depth at the edge of the pupil, giving the pupil an irregular shape. Coloboma may be associated with hereditary conditions, trauma to the eye, or eye surgery.
Review Date 11/4/2015
Updated by: Franklin W. Lusby, MD, ophthalmologist, Lusby Vision Institute, La Jolla, CA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.