Stargardt disease

Stargardt disease is an inherited condition affecting the light-sensitive retina at the back of the eye.

Usually starting in childhood or the teenage years, it causes progressive loss of central vision. Progressive means symptoms increase with time. It doesn't cause total sight loss, but people often need extra support to make the most of their vision.

What is Stargardt disease?

Stargardt disease is an inherited eye disease that progressively damages the light-sensitive tissue at the back of the eye. It's also known as Stargardt macular dystrophy, fundus flavimaculatus, and juvenile macular degeneration.

The condition causes degeneration of the macula, the part of the eye responsible for our central vision. This leads to blurred and distorted vision, difficulty with colour vision, and eventually a gap in the centre of your vision.

There's currently no treatment to stop or reverse its effects. However, peripheral vision (side vision) isn't affected, and there is support to help you adapt to the central vision loss it causes.

Stargardt disease symptoms

Symptoms of Stargardt disease usually begin in childhood or the teenage years, although sometimes they don't develop until later in adulthood.

The condition affects the central vision we use for seeing details when we read, watch TV, and drive, for example.

Symptoms typically include:

• Blurred vision - you may see things as distorted or wavy.
• Blank or blind spots at the centre of your vision - as it progresses, you might have a permanent gap in your central field of vision.
• Difficulty adjusting to changing light levels - your eyes may struggle to adjust when you move from light to dark or dark to light environments (known as dark-adaptation).
• Sensitivity to bright light.
• Colour blindness - this can affect some people as the disease progresses.

What causes Stargardt disease?

Stargardt disease is a rare genetic disease inherited from parent to child.

It can be inherited from one parent who has the condition and the faulty gene, with a 50% chance of it passing to their children (known as dominant inheritance). It can also be inherited when both parents have the faulty gene but not necessarily the condition itself, with a 25% chance of passing it to their children. This is known as recessive inheritance.

The ABCA4 gene is most commonly involved with the disease, though others have been identified, including genes called ELOVL4 and PROM1.  When you have Stargardt disease, the way the body processes by-products of vitamin A is affected. This results in a build-up of fatty deposits in light-sensitive photoreceptor cells in the retina at the back of the eye. The gene involved in the disease is responsible for the protein we need to clear these by-products.

With this disease, a fault in the gene means the protein is missing, causing lipofuscin accumulation, where this fatty material collects in yellowish flecks in the macula. 

Stargardt disease treatment

There aren't currently any treatments for Stargardt disease, but there are many ways to make the most of your vision. 

Your optician or ophthalmologist will want you to have regular follow-ups to monitor the progress of the condition. They can also refer you for a low vision assessment which can identify helpful services, aids, and techniques.

Research, including clinical trials, is underway to find possible treatments for the disease. These could include gene-based therapies and stem cell treatment.

Getting a Stargardt diagnosis

If you notice changes to your sight, or are concerned about your child's sight, visit an optician.

They can check for Stargardt disease by looking at the retina for signs of the yellowish flecks it causes due to the collection of fatty materials (lipofuscin).

The impact on your vision can be assessed with standard eye tests and other tests, including: 

• Optical coherence tomography (OCT) - a straightforward non-invasive test, a bit like an ultrasound, which takes a detailed image of the retina.

• Visual field testing - which creates a map of your visual field (finding any blind spots) and is a simple test often done by opticians.

• Electroretinography (ERG) - which measures signals produced by the retina in response to light flashes, and can reveal abnormalities from degenerative retinal diseases, including Stargardt disease.

• Autofluorescence imaging - using a special camera to measure fluorescence in retinal cells.

• Genetic testing - which may reveal the specific gene involved in causing the disease.

When to get medical advice

According to NHS advice, we should get our eyes tested every two years.

This is even more important if there's any history of eye conditions in your family.

Living with Stargardt disease

Being diagnosed with an eye condition that will affect you or your child's sight can understandably be very upsetting.

It's even harder to hear that this is a condition without treatments. You don't have to struggle alone; there is emotional and practical support to help children and adults make the most of their vision.