In a previous post, we covered common eye diseases like macular degeneration, diabetic retinopathy, and glaucoma. In this post, we look at three rare diseases of the eye: Retinitis pigmentosa, optic neuritis, and Stargardt’s disease.

 

Retinitis Pigmentosa

 

What it is: 

Also called RP, retinitis pigmentosa is actually a genetic disorder that affects roughly 1 in 4,000 people and can lead to sight loss. RP affects the retina’s photoreceptors (the cells that gather light, called rods and cones). 

Risk factors and symptoms: 

RP is inherited via gene mutations. More than 60 different genes can cause the different types of RP. 

For many with RP, symptoms start in childhood. It usually affects the rods first, the cells that are responsible for helping you see in low light and for your peripheral vision. Often one of the first symptoms is a loss of night vision, followed by peripheral vision loss. 

RP can progress to affect cones, which are the cells that help you see color and fine detail, resulting in color blindness and loss of central vision. By middle age, many with RP are legally blind. 

Treatment:

There is no cure, but there are treatment options that can slow vision loss and potentially restore some sight. Some of these treatments include: 

• Wearing sunglasses to reduce light sensitivity and protect your eyes from UV rays that could accelerate vision loss. 
• A medication called acetazolamide, which can reduce swelling of the macula to improve vision. 
• High doses of Vitamin A palmitate can slow the progression of RP, but need to be administered under the direction of a doctor (too much can be toxic). 
• Retinal implants paired with glasses can help provide partial sight. 
• Potential new treatments are being studied, and involve replacement of damaged cells or tissues and gene therapy. 

Low vision aids and mobility training can also help people with RP. 

 

Optic Neuritis

 

What it is: 

Optic neuritis (ON) is an inflammation of the optic nerve (the nerve that sends messages from your eye to your brain) that can flare up suddenly, causing temporary vision loss. It usually affects one eye. 

Risk factors and symptoms: 

ON can occur with a number of conditions, infections or immune diseases. One of the most common is multiple sclerosis. Sometimes ON can be the first indication of MS, but it can also occur in people who have already been diagnosed with MS. 

It most often affects adults between 20 and 40, and women are more likely to develop ON. 

Beyond vision loss, symptoms can include pain or dull ache behind the eye, loss of vision in one eye, field of vision loss (such as central or peripheral vision), loss of color vision, and flashing lights. 

Treatment: 

An ophthalmologist will conduct a routine eye exam and administer some additional tests to diagnose ON. Many people recover from an ON episode without treatment within six months, but sometimes steroid medications are prescribed to reduce inflammation of the optic nerve. 

 

Stargardt Disease

 

What it is: 

Stargardt disease, also called fundus flavimaculatus, is an inherited form of macular degeneration that affects 1 in 20,000 children and young adults. Stargardt’s develops between the ages of six and 20 and causes the photoreceptors to die off, leading to a loss of central vision. 

Risk factors and symptoms: 

Stargardt disease is inherited and is most commonly caused by a mutation in the ABCA4 gene. Symptoms can include blurred vision or distorted or dark areas in the central vision, as well as trouble seeing colors. For most people with Stargardt disease, peripheral vision won’t be affected. 

Treatment: 

There’s no cure for Stargardt disease, but gene therapy and embryonic stem cell treatments are currently being tested. Wearing sunglasses to protect the eyes from harmful UV rays can sometimes help prevent further damage to the retina. 

 

When to see an eye doctor

 

If you experience sudden changes in your vision, including loss of any part of your vision, or eye pain, make sure to schedule an appointment with your eye doctor right away. 

Do you need to schedule your routine eye exam? Make an appointment here today.