Williams syndrome is a rare genetic condition resulting from the deletion of a small piece of chromosome 7, which occurs randomly during the formation of sperm or egg cells. Affecting approximately one in 10,000 people, it causes a distinct set of physical and developmental characteristics. These often include unique facial features, cardiovascular issues, and a cognitive profile with strong verbal skills and a very friendly personality.
The “Starburst” Eye Pattern
A distinctive feature of Williams syndrome is a lacy, star-like pattern in the iris, called a “starburst” or stellate pattern. This design is most apparent in individuals with blue or green eyes, where the contrast allows the pattern to be seen more clearly.
The cause is a change in the iris stroma, the front layer of the iris, which is linked to the deletion of the elastin gene on chromosome 7. This results in less pigment and a different arrangement of fibers in this layer. While this pattern is a common characteristic, it does not, by itself, affect vision.
Common Vision and Eye Structure Issues
Individuals with Williams syndrome experience a higher incidence of specific vision problems. One of the most common is strabismus, or “crossed eyes,” where the eyes do not align properly. This condition can affect depth perception and may lead to a permanent reduction in vision in the turned eye if not addressed.
Other common eye and vision issues include:
- Refractive errors, particularly hyperopia (farsightedness), which causes distant objects to be seen more clearly than near ones.
- Epicanthal folds, which are small skin folds on the inner corner of the eyes.
- Periorbital puffiness, which is a fullness around the eyes.
- An increased likelihood of developing cataracts, a clouding of the eye’s lens, at an earlier age.
Managing Eye Health in Williams Syndrome
Proactive eye care is an important part of managing health in Williams syndrome. Early and consistent examinations by a pediatric ophthalmologist are recommended to identify and address issues promptly. Starting these evaluations in infancy helps detect conditions that can have long-term impacts on visual development.
Prescription eyeglasses are the standard treatment for farsightedness. Strabismus treatments include using an eye patch over the stronger eye to improve vision in the weaker one, or surgery to realign the eye muscles. Regular monitoring is also necessary to watch for early cataract development so intervention can be planned if sight is affected.