Coloboma is a congenital gap or defect in ocular structures caused by incomplete closure of the embryonic fissure. It can involve the iris, lens, retina, choroid, or optic nerve.
Presentation
Severity depends on which structures are affected.
- Iris coloboma producing a keyhole-shaped pupil but often good vision
- Retinochoroidal or optic nerve coloboma causing field defects and reduced acuity
- Association with microphthalmia and systemic syndromes in some cases
- Often bilateral, with variable refractive errors
Management
Treatment is supportive and preventative.
- Glasses, contact lenses, and sometimes cosmetic iris devices
- Amblyopia therapy and low-vision support where needed
- Monitoring for retinal detachment around the coloboma edges
- Genetic and systemic evaluation if syndromic features are present
