Coloboma of the iris: what is this, causes, symptoms, diagnostics, treatment, prevention

Coloboma of the iris; Keyhole pupil; Cat eye; Iris defect

Iris coloboma is an eye disease, characterized by a slit or notch in the colored part of the eye. It's innate (present at birth) disease, which affects the development of the eye in utero. Iris coloboma can affect one or both eyes and cause vision problems, depending on the size and location of the gap.

What is an iris coloboma?

Iris coloboma is an eye disease, in which in the colored part of the eye (IRIS) there is a gap or notch. The iris is part of the eye, which gives it color and helps control the amount of light, getting into the eye. In iris coloboma, the fissure or notch can be anywhere in the iris and can range in size from small to large.

Causes of iris coloboma

Coloboma of the iris is a congenital disease, i.e. present at birth. It is caused by the inability of the embryonic cleft to close properly during the development of the eye in utero.. This results in a gap or notch in the iris.

Symptoms of an iris coloboma

The most common symptom of an iris coloboma is a tear or notch in the colored part of the eye.. This is easy to see when viewed with a slit lamp.. In some cases, the gap or notch can be so small, that are not visible to the naked eye. Other symptoms of iris coloboma may include blurred vision, double vision and sensitivity to light.

When to contact a healthcare professional

If you or your child has a gap or notch in the colored part of the eye, it is important to contact a healthcare professional for evaluation. Slit lamp examination may be used to confirm the diagnosis of iris coloboma.

Questions, that your doctor may ask

Your doctor may ask you a number of questions, to help diagnose iris coloboma. These questions may include:

• Is there a gap or notch in the colored part of the eye?
• Is there a gap or notch in one or both eyes?
• What is the size of the gap or notch?
• Are there any other symptoms, such as blurred vision or double vision?
• Is the eye sensitive to light??

Diagnosis of coloboma of the iris

Iris coloboma is usually diagnosed with a slit lamp examination.. This study uses a special microscope to examine the eye in detail.. The doctor will be able to see the gap or notch in the colored part of the eye and determine the size of the gap or notch..

Treatment of iris coloboma

Treatment for an iris coloboma depends on the size and location of the tear or notch. In some cases, treatment may not be required. For larger gaps or notches, treatment may include corrective lenses, surgery or laser therapy.

Home treatment for iris coloboma

If you or your child has iris coloboma, it is important to protect the eye from injury. This includes wearing safety goggles when participating in activities., which can cause eye injury, eg, when playing sports. It is also important to see a doctor regularly., to take care of your eyes.

Prevention of iris coloboma

Coloboma of the iris is a congenital disease, so it can't be prevented.. Nonetheless, it is important to seek medical attention, if you or your child has a gap or notch in the colored part of the eye. Early diagnosis and treatment can help prevent vision problems.

Used sources and literature

Brodsky MC. Congenital optic disc anomalies. In: Yanoff M, Tablecloths JS, eds. Ophthalmology. 5th ed. Philadelphia, PA: Elsevier; 2019:chap 9.5.

friend KB, Saraf D, Mieler WF, Yannuzzi LA. Congenital and developmental anomalies of the optic nerve. In: friend KB, Saraf D, Mieler WF, Yannuzzi LA, eds. The Retinal Atlas. 2nd ed. Philadelphia, PA: Elsevier; 2017:chap 15.

National Eye Institute website. Coloboma. www.nei.nih.gov/learn-about-eye-health/eye-conditions-and-diseases/coloboma. Updated December 3, 2021. Accessed January 28, 2022.

Olitsky SE, Marsh JD. Abnormalities of the pupil. In: Kliegman RM, St. Geme JW, Bloom NJ, Shah SS, Tasker RC, Wilson KM, eds. Nelson Textbook of Pediatrics. 21st ed. Philadelphia, PA: Elsevier; 2020:chap 640.

Wear D. American Academy of Ophthalmology website. What is a coloboma? www.aao.org/eye-health/diseases/what-is-coloboma. Accessed January 28, 2022.