What is Aniridia?
Aniridia is a genetic condition that affects people at birth. The term “aniridia” literally means “without iris” (the colored part of the eye), which is generally the first indication that an individual has aniridia. A person who has aniridia is born without a fully developed iris. The name ‘aniridia’ is somewhat misleading because aniridia is a panocular condition, meaning it usually affects other components of the anatomy of the eye in addition to the iris.
Actually, the lack of the iris is the least of the ocular problems associated with aniridia. Aniridia can affect the entire anatomy – the cornea, the fovea or retina, as well as the lens. As a result, ocular conditions can include glaucoma, foveal hypoplasia, nystagmus, strabismus, dry eye, corneal degeneration, and cataracts. Most people with aniridia have at least one of these associated ocular conditions that impact their vision.
Aniridia is a rare eye condition, affecting approximately 1 in 60,000 births. However, the ocular problems associated with aniridia mentioned above are quite common. What is rare is to have all of these conditions present in one individual.
Although people with aniridia always have vision problems, the degree varies greatly and is dependent upon which complications, in addition to the lack of iris, an individual has. Generally, individuals with aniridia have a visual acuity measurement between 20/80 and 20/200. Some are legally blind, while others have vision good enough to drive a car. Most individuals with aniridia read without using Braille, especially in today’s technically advanced environment of e-Readers.
It is important to note that some of the conditions related to aniridia are non-degenerative (meaning they do not get worse over time) and others are degenerative. Conditions that can degenerate the vision of an individual with aniridia include corneal keratopathy, glaucoma, and cataracts. For more information on these conditions and treatments, please refer to the menu on the right ‘Aniridia’s Impact on Vision’ under the ‘Learn More’ heading.
How is Aniridia Diagnosed?
Aniridia is generally diagnosed by a pediatric ophthalmologist. Many times, during a routine medical exam, a pediatrician will notice that a baby with aniridia does not have a pupil reaction to light (i.e. the iris is not contracting or expanding). A qualified ophthalmologist usually diagnoses aniridia. In addition, a blood test performed by a geneticist can confirm the genetic mutation. For more information on genetic testing, contact a qualified genetic counselor. Genetic counselors are generally affiliated with universities and/or children’s hospitals.
How Can I Learn More About Aniridia?
To learn more about aniridia, how aniridia impacts vision, other medical concerns, and suggestions if your child is newly diagnosed, please click on the menu items to the right of this page just under the ‘Learn More’ heading. To read about other families’ perspectives on living with aniridia click on the section just below this paragraph titled ‘Family Perspectives’.