Stargardt's Disease (Fundus Flavimaculatus)

While macular degeneration generally is associated with aging eyes, an inherited form known as Stargardt's disease (STGD) can affect children and young adults. Stargardt's, often mistakenly called Stargate's, also sometimes is known as fundus flavimaculatus. However, some researchers believe a distinction should be made between the two terms, because each describes a different variant of the eye disease.

Stargardt's generally refers to a group of inherited diseases causing light-sensitive cells in the inner back of the eye (retina) to deteriorate, particularly in the area of the macula where fine focusing occurs. Central vision loss also occurs, while peripheral vision usually is retained.

Stargardt's is diagnosed by the presence of small, yellowish spots of deteriorating tissue (drusen) sloughed off from the colored or outer covering of the retina (retinal pigment epithelium). Progressive vision loss eventually leads to blindness in most cases.

Stargardt's disease usually is thought to be passed along to children when both parents carry gene mutations causing the eye disease. Parents can carry recessive genetic traits responsible for Stargardt's, even though they themselves may not have the disease.

Researchers have found that about 5 percent of the human population carry gene mutations causing inherited retinal diseases such as Stargardt's and retinitis pigmentosa.*

Vision loss from Stargardt's generally begins to show up within the first 20 years of a young person's life, particularly in early childhood.

But it's difficult to pinpoint exactly when retinal damage will occur or how fast it will progress, because variations can occur even among family members with similar inherited tendencies. For example, one study reported in the May 2006 issue of American Journal of Ophthalmology noted the case of three siblings, two of whom showed signs of retinal disease in early childhood. But the third sibling was affected beginning at around age 19.

In some cases, a person with Stargardt's (particularly the fundus flavimaculatus version of the disease) may reach middle age before vision problems are noticed. The reference book Ophthalmology notes that vision loss from Stargardt's as measured on a standard eye chart can range between 20/50 and 20/200. (In the United States legal blindness is defined as 20/200 while wearing corrective lenses.) Those who have the fundus flavimaculatus form of the disease, however, are likely to experience even more severe vision loss.

Symptoms of Stargardt's can include blurry or distorted vision, inability to see in low lighting and difficulty recognizing familiar faces. In late stages of Stargardt's, color vision also may be lost.
 

Some research indicates that exposure to bright light may play a role in triggering the retinal damage that occurs with Stargardt's. While there is no known treatment for Stargardt's disease at this time, people with the condition often are advised to wear eyeglasses or sunglasses with UV protection to reduce the possibility of additional eye damage caused by the sun. Your eye doctor may also suggest that you wear special filters in eyeglasses to block certain wavelengths of light.

In 2004, UCLA School of Medicine researchers reported promising results when the acne drug Accutane (isotretinoin) was injected into the eyes of mice to help prevent formation of pigmented waste deposits in the eye. These wastes, caused by abnormal processes associated with defective genes in Stargardt's, accumulate in and progressively damage the retina to cause ultimate vision loss.

Vitamin A supplementation should be avoided if you have Stargardt's, because some researchers believe gene mutations lead to abnormal synthesis of the vitamin in the eye, which may help cause associated retinal damage.

The American Macular Degeneration Foundation recommends that people with Stargardt's or a history of the eye disease in close family members obtain genetic counseling before starting their own families.

Because vision loss often appears in young children with Stargardt's, low vision counseling from your eye doctor is essential to make sure that classroom learning is not hampered. For example, a child with Stargardt's may need to use large print books and special devices that magnify print. [Read more about low vision devices.]