Originally described by German ophthalmologist Karl Stargardt in 1901, for whom it is named, Stargardt’s Disease is a retinal disorder that affects themacula early in life and hence is often called Juvenile Macular Degeneration or Early Onset Macular Degeneration. Unlike Age-related Macular Degeneration, there is never a leakage of blood or fluid, though the same area of the retina(the macula) is affected.
The macula is the central part of the retina that is responsible for providing sharp detail and color vision. As in Age-related Macular Degeneration, Stargardt’s Disease does not affect the peripheral retina and as a result individuals do not lose all of their vision. They can usually walk and engage in general activities with little difficulty. Reading and seeing details such as signs and faces at a distance are however affected. Stargardt’s disease affects over 30,000 individuals in the US and occurs in approximately one in 10,000 individuals.
Stargardt disease is the most common cause of Macular Degeneration and central visual loss in young people. It often develops in the teens or twenties, in both genders, but may develop in younger children and even sometimes later in life. It affects both eyes, though one may be worse than the other. In certain more rare types the peripheral vision may also be affected. Vision loss tends to progress rapidly at first, but usually stabilizes at about 20/200 (6/60) visual acuity.
Stargardt’s Disease is also known as:
- Juvenile Macular Degeneration
- Juvenile Onset Macular Degeneration
- Stargardt Disease
- Fundus Flavimaculatus
- Stargardt Macular Dystrophy
Stargardt’s Disease is classically described as having a “beaten metal” appearance in the macula area of the retina. Often, early in the disease, the retina appears normal, and a diagnosis may be difficult to make. Ultimately the retina begins to change in appearance and the diagnosis becomes more definitive. Three tests are used to determine a diagnosis of Stargardt’s disease:
- Fluorescein Angiography
Fundus Flavimaculatus, a form of Stargardt’s Disease which presents with flecks lipofuscin (lipid rich waste deposits) distributed throughout the retina.
Exciting genetic and stem-cell research is presently being conducted to explore ways to treat Stargardt’s Disease. It is worthwhile to be familiar with the NIH website that lists Clinical Research Trials that you might be eligible to partake in.
Visual Acuity and Color Vision
Stargardt’s disease may first be detected by a mild loss of visual acuity or sharpness of vision and the individual may think that they just need eyeglasses. In the early stages, however, vision may be near normal. It is not unusual for visual acuity measurements to vary moderately from day-to-day and this should not be assumed to be a worsening of the disease. Best-corrected visual acuity can range between 20/100 to 20/400, however many individual retain vision at the 20/200 level. While it is the cones in the retina that provide us with both color and detail vision, and the cones are most concentrated in the macular area, it is surprising that despite themacula disorder at least some degree of color vision is usually retained in Stargardt’s Disease.
Visual Field (Field of view)
As Stargardt’s disease progresses, small blind spots (scotomas) often develop in the central visual field as if there is a hole in one’s vision. Images that fall on these blind spots will disappear, and as the direction the eye looks moves they may reappear causing an on-and-off effect. Often individuals with Stargardt’s Disease will learn to look “off-center” in order to reposition their blind spot out of the way. This is called eccentric viewing and it helps the individual to maximize their vision, while it may appear unnatural to the rest of us (as if they’re not looking directly at us). In Stargardt’s Disease one’s peripheral vision remains normal.
Light and Dark Adaptation
Individuals with Stargardt’s Disease will experience more difficulty adapting to different light levels. This is because in Stargardt’s Disease the photoreceptors (rods and cones) have difficulty regenerating the light-sensitive pigments (Rhodopsin) fast enough to adapt to large changes in illumination—making going into a dark room more difficult, and adapting to bright sunlight even painful (photophobia). The use of special wrap-around sunglasses in special colors and hats with visors can help lessen these difficulties.
Vision loss from Stargardt’s Disease responds very well to magnification which can makereading, seeing signs, faces, the computer, TV and even driving a possibility. There is a wide range of optical, electronic and software magnification options to address virtually every need.
Every individual with Stargardt’s Disease should have a low vision examination by a doctor skilled in low vision rehabilitation to help identify the most appropriate options to enhance their visual functioning, academic and vocational potential and their personal quality of life.