What is a coloboma?
Coloboma is a condition characterized by the lack of development of a part of the eye, usually the iris. Thus, coloboma can be classified into several types according to the affected part of the eye:
- Coloboma of the iris (colored part of the eye).
- Coloboma of the eyelid
- Coloboma of the lens (the part of the eye that focuses light on the retina)
- Macular coloboma (of the macula, the central part of the retina responsible for providing detailed vision, daylight and color)
- Coloboma of the optic nerve (group of nerve fibers that transmit light signals to the brain).
- Uveal coloboma (of the uvea, the middle layer of the eye).
- Chorio-retinal coloboma (part of the retina).
What are the symptoms of coloboma?
Symptoms depend on the area affected. For example, if it affects the iris, it has the appearance of a cat’s eye or a keyhole, or, if it affects the eyelid, it is noticed that it is not fully developed.
Depending on the size, some types of coloboma can cause a loss of vision, which can be reduced vision, blurred vision, or no vision in a specific location of the visual field. Another symptom that occasionally occurs is an increased sensitivity to light.
What are the causes of coloboma?
Most are congenital, meaning they are present from birth. In most cases the cause is unknown; but sometimes it can occur due to eye surgery, hereditary conditions or trauma to the eye.
What is the treatment for coloboma?
There is no definitive cure for coloboma, and treatment depends on the type of coloboma. If it affects the iris, colored contact lenses can be used to disguise its appearance, or it can be corrected with surgery.
In other types of coloboma, it is necessary to help the patient adjust to his or her vision problems with low vision devices. Other problems caused by coloboma, such as new blood vessel growth in the back of the eye or cataracts, may also be treated.
Finally, the specialist may recommend specific treatments if the patient only has coloboma in one eye, such as patching, eye drops, glasses, among others. This helps prevent the development of amblyopia (lazy eye) and improve vision even in severe cases.