Coloboma

Coloboma is a gap in one of the structures of the eye, present from birth, that can affect vision depending on its size and location.

Common symptoms

Variable — from no symptoms to reduced vision, an unusually shaped pupil, sensitivity to light, or a blind area in the field of vision.

Description

Coloboma is caused by incomplete closure of the structures of the eye during early development in the womb. It can affect the iris, lens, retina, choroid, or optic nerve, in one or both eyes.

The impact on vision depends on which part of the eye is involved and how large the gap is. Small iris colobomas may cause little more than an unusually shaped pupil, while colobomas involving the retina or optic nerve can significantly affect sight.

There is no treatment to repair a coloboma itself, but glasses, low vision aids, and support at school or work can help. Children with coloboma should have regular eye checks to monitor for other complications such as cataract, glaucoma, or retinal detachment.