Prescription eyeglasses are more common in individuals with Down syndrome than in the general population. Refractive errors, or alterations in the shape of the eye, are often the cause of vision impairment. This refractive error can result in hyperopia (farsightedness), myopia (nearsightedness), or astigmatism (a combination of both). Refractive errors can be corrected with eyeglasses or contacts.
Of greater concern are congenital cataracts (present at birth) and acquired cataracts (develop later). Cataracts appear as cloudiness in the lens of the eye. They can be large or small. If cataracts are present from early in a child’s life, then a clear image is not delivered to the brain, and the brain does not “learn” to see. If the cataract is not removed, it can result in lifelong vision impairment. This is what makes early detection of cataracts in infants and children so important. A child with Down syndrome should be evaluated at birth and referred to an ophthalmologist (a doctor who has completed training in medical and surgical care of the eye) if cataracts are detected. Regardless of the findings at birth, all children with Down syndrome should see an ophthalmologist in the first six months of life who will again test for cataracts. Individuals should continue to be followed by an ophthalmologist throughout their lifespan.
Glaucoma occurs occasionally and causes a buildup of pressure in the eye. It can damage the optic nerve resulting in vision loss if not controlled. Proper treatment is important and may include eye drops, oral medications, laser treatment, or surgery.
Keratoconus is an eye disease that usually occurs during or after puberty. It can cause corneal thinning or haze and blurred vision. Eyeglasses are used as an early treatment. As the disease progresses, corneal collagen cross-linking can be used. This involves a solution being applied to the eyes followed by ultraviolet light which causes new collagen bonds to form. In advanced stages, surgical options may be considered. Keratoconus is extremely common in individuals with Down syndrome.
Many individuals with Down syndrome have tear duct abnormalities. Family or caregivers may notice frequent tearing or discharge from the eyes that becomes worse during colds. Often the first line of treatment is massage over the space between the eye and the nose (tear sac region) 2-3 times a day to attempt to open the tear duct. If the symptoms continue, the tear ducts may need to be opened by a surgical procedure.
Blepharitis is inflammation of the eyelids. Symptoms include redness at the edge of the lids and crusting around the lashes. It may cause a feeling of dryness or burning. Treatment usually consists of eyelid hygiene and topical antibiotics.
Other Common Issues
Other common eye issues in individuals with Down syndrome include strabismus (one or both eyes turn inward or outward), amblyopia (“lazy eye” with vision impairment), and nystagmus (involuntary movement of the eyes). Strabismus does not necessarily cause vision impairment. It can be treated with eyeglasses, eye patching, and (in severe cases) surgery. Left untreated, strabismus can cause amblyopia. Amblyopia occurs when vision does not develop normally due to the eyes being misaligned and results in vision loss. Nystagmus is an involuntary side-to-side, up and down, or circular movement of the eyes. It typically involves both eyes. Nystagmus may go away on its own with time, be managed with eyeglasses or contacts, or (in severe cases) require surgery.