Pregnancy SmartSite^TM

• Home
• Email
• Site Map
• Contact

• Normal Pregnancy
• Labor & Delivery
• Complications
• After Your Child Is Born

Normal Pregnancy

Staying Healthy

Alcohol and pregnancy Managing your weight gain in pregnancy Steps to take before you get pregnant When you need to gain more weight during pregnancy

What to expect during pregnancy

Aches and pains during pregnancy Choosing the right practitioner Common symptoms during pregnancy Hyperemesis Gravidarum Morning sickness Pregnancy and travel Pregnancy and work Problems sleeping during pregnancy Skin and hair changes during pregnancy Teenage pregnancy

Preparing to go home with your baby

Cribs and crib safety Eat right during pregnancy Preparing your other children

Visits and Tests

Amniocentesis Chorionic villus sampling Genetic counseling before pregnancy Glucose tolerance test-pregnancy Monitoring your baby before labor Nuchal translucency Prenatal care in your first trimester Prenatal care in your second trimester Prenatal care in your third trimester

Coloboma of the iris

Definition

Coloboma of the iris is a hole or defect of the iris of the eye. Most colobomas are present since birth (congenital).

Considerations

Coloboma of the iris can look like a second pupil or a black notch at the edge of the pupil. This gives the pupil an irregular shape. It can also appear as a split in the iris from the pupil to the edge of the iris.

A small coloboma (especially if it is not attached to the pupil) may allow a second image to focus on the back of the eye. This may cause:

• Blurred vision

• Decreased visual acuity

• Double vision

• Ghost image

If it is congenital, the defect may include the retina, choroid, or optic nerve.

Most colobomas are diagnosed at birth or shortly afterward.

Causes

Most cases of coloboma have no known cause and are not related to other abnormalities. Some are due to a specific genetic defect. A small number of people with coloboma have other inherited developmental problems.

When to Contact a Medical Professional

Contact your health care provider if:

• You notice that your child has what appears to be a hole in the iris or an unusual-shaped pupil.

• Your child's vision becomes blurred or decreased.

In addition to your child, you may also need to see an eye specialist (ophthalmologist).

What to Expect at Your Office Visit

Your provider will take a medical history and do an exam.

Since the problem is most often diagnosed in infants, knowing about the family history is very important.

The provider will do a detailed eye exam that includes looking into the back of the eye while the eye is dilated. An MRI of the brain, eyes, and connecting nerves may be done if other problems are suspected.

References

Brodsky MC, Houghton O. Congenital optic disc anomalies. In: Yanoff M, Duker JS, eds. Ophthalmology. 6th ed. Philadelphia, PA: Elsevier; 2023:chap 9.5.

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

National Eye Institute (NIH) website. Coloboma. www.nei.nih.gov/learn-about-eye-health/eye-conditions-and-diseases/coloboma. Updated November 15, 2023. Accessed December 6, 2023.

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

Porter D. American Academy of Ophthalmology website. What is a coloboma? www.aao.org/eye-health/diseases/what-is-coloboma. Accessed December 6, 2023.

Selzer EB, Blain D, Hufnagel RB, Lupo PJ, Mitchell LE, Brooks BP. Review of evidence for environmental causes of uveal coloboma. Surv Ophthalmol. 2022;67(4):1031-1047. PMID: 34979194 pubmed.ncbi.nlm.nih.gov/34979194/.

Review Date: 11/8/2023

Reviewed By: Franklin W. Lusby, MD, Ophthalmologist, Lusby Vision Institute, La Jolla, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.