Stargardt's Disease (Fundus Flavimaculatus)
By Marilyn Haddrill; reviewed by
Dr. Vance Thompson and
Dr. Geoffrey Tufty
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.
What Causes Stargardt's Disease?
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.*
How Fast Does Stargardt's Progress?
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.
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