Whenever we hear the term “macular degeneration” we often hear it with a preceding term: age-related. All the oldsters feel a wave of panic while the youngsters sigh with relief. There’s still time to prevent it. But what if I were to tell you that macular degeneration isn’t just for the elderly? Children and teens can also be affected by a form of macular degeneration called Stargardt’s Disease.
Stargardt’s Disease is the most common hereditary macular degeneration. Experts believe that one in ten thousand people are born with Stargardt’s disease. It may be a rare disease, but it is a severe one, nonetheless.
What Is It?
Stargardt’s Disease is a form of macular degeneration named after Karl Stargardt. This German ophthalmologist was the first known person to have the disease in 1901. Stargardt’s Disease often affects young children and teens who have inherited certain genes from their parents. These genes allow the disease to develop.
This disease is the result of the death of the photoreceptors in the retina of the eye. Though age-related macular degeneration can affect one or both eyes, Stargardt’s Disease often affects both eyes.
With this comes partial vision loss. Those with Stargardt’s Disease don’t lose their eyesight completely because it does not affect the periphery.
Stargardt’s Disease is especially damning because it means the deterioration of arguably the most important part of the eye. The photoreceptors are in charge of gathering information for the brain to then turn into comprehensive images. This function is also known as sight.
With damaged or dead photoreceptors, the brain can’t produce a clear image because crucial visual information may be missing.
Without the retina and all its cells working properly, children and teens will have trouble reading, seeing faces, watching television or playing video games. Personally, I don’t want to imagine a childhood without any of those things!
Stargardt’s Disease typically develops in childhood or during the adolescent years. However, it is possible for someone to carry the Stargardt’s Disease gene and develop the disease later in adulthood. No matter when the disease sets in, vision loss progresses slowly going from normal 20/20 vision to 20/200.
Symptoms of Stargardt’s Disease
One of the major problems with Stargardt’s Disease is the varying symptoms. No individual experiences the disease the same way as another. Therefore many people experience various symptoms. Though we’ve found the most common symptoms associated with the disease, they by no means apply to every person with Stargardt’s Disease.
One common symptom is a slow but progressive loss of central vision in both eyes. When this happens, it becomes difficult for children and teens to focus. Reading becomes more difficult and so does being in school as almost all learning is visual.
Sports and other outdoor activities may also prove challenging for a child or teen suffering from the disease. Poor coordination may be caused by a lack of central vision, not necessarily being bad at sports.
Another symptom is seeing flecks or spots in their vision. Depending on the person the colors and shapes of these flecks can change. Some people have reported seeing yellow and gray flecks, while others say they see black or hazy spots in their central vision.
Often, eyes with damaged or dead photoreceptors will have trouble adjusting to bright lights. Moving from dark settings into light ones and vice versa may take the eyes a while to adjust. Light sensitivity is also a related symptom.
In the later stages of the disease, some people have developed color blindness as the photoreceptors are in charge of capturing color.
Although vision loss is generally slow in Stargardt’s Disease patients, sometimes when the disease sets in early in life, vision loss can be quick. Vision loss will begin slow, then take a steep dive until it eventually levels off at 20/200 vision or worse.
If you think you or your child may have Stargardt’s Disease, visit your eye health care professional immediately. Your eye doctor will be able to affirm or hopefully debunk your theory by examining the retina. By doing so, they will be able to see if there are flecks in the macula.
Some common tests are:
- A fundus photo: a photo of the retina
- Optical coherence tomography: like an ultrasound for the eye
- Electroretinography: measures the photoreceptors response to light. Irregular response patterns can mean Stargardt’s Disease
- Color testing: to test for color blindness later in the disease
Ask your doctor for more information about their preferred method of diagnosis.
Unfortunately, no cure exists yet for Stargardt’s Disease. Since it’s an inherited disease, its presence is deeply rooted in a person’s genetic composition. However, this is also good news as stem cell researchers are on their way to developing gene therapy methods to hopefully correct faulty genes.
Current treatments do exist, such as special UV-protectant sunglasses that can help the eyes adjust to various lightings. Low vision lifestyles are also encouraged for those living with Stargardt’s Disease.
A low vision lifestyle can mean many things. Adapting it to your specific needs is what is most important. You can find more comprehensive articles about low vision living on our blog.
How Is It Inherited?
Ah, yes. The question you’ve been asking yourself since the beginning of this article. How is Stargardt’s Disease inherited?
Like all inherited diseases it begins with the parents. Individuals carry a gene called ABCA4. The ABCA4 gene is paired with a “normal” or non-mutated gene. Because of this, parents are not affected by the disease. For Stargardt’s to develop, you need to possess two ABCA4 genes that pair together.
When a child is born with Stargardt’s Disease, it’s because they inherited two ABCA4 genes: one from each parent. When both parents carry the ABCA4 gene, there is a 25 percent chance that the child will develop Stargardt’s Disease.
Sometimes, only one parent will carry the gene, but it can still be passed down to the child if the mutated gene is the dominant one.
Though Stargardt’s Disease is over 100 years old, genetic and stem cell research is relatively new. Hopefully, as more people become aware of this disease, researchers will find new ways to treat and cure it.