Retinitis Pigmentosa: Definition, Causes and Treatment
September 26, 2024 • 11:35 AM
As you might have guessed from the name, retinitis pigmentosa is the name given to a group of different eye problems that cause harm to the retina. In this article, we’ll take a look at the problems that fall under this title, potential causes, diagnosis methods, and the different ways you can treat them.
At Pair Eyewear, we’re all about eye health, which is why we’re walking through the key information you need.
What Is the Retina?
Before we dive into retinitis pigmentosa, we need to back up and define the retina because it’s a word that gets tossed around frequently but, scientifically speaking, refers to a very specific part of your eye.
The retina is the layer (made up of photoreceptor cells and glial cells, in case you were wondering) at the back of your eye that converts light into electrical signals. Your brain uses these photons and turns them into the visual picture that you perceive.
If you’ve ever had an eye exam, you’ve likely had your retina checked by your eye doctor. In some offices, they can take high-definition pictures of your retina. Other times, an eye doctor will use a bright light mounted on their head and a condensing lens to see your retina and other parts of your eye.
What Is Retinitis Pigmentosa?
Now that you have a basic understanding of what the retina is, it’s time to move on to retinitis pigmentosa (RP).
RP is the name given to a group of genetic conditions that affect your retina. In terms of inherited eye diseases, RP is the most common. That said, it’s still considered a rare retinal disease on the whole, given that it affects roughly two million people in the world.
Some of the diseases that fall under this category include:
- Usher syndrome
- Leber congenital amaurosis
- Congenital stationary night blindness
- Cone-rod dystrophy
RP causes the retina to break down over time, usually fairly slowly. Generally speaking, the symptoms of RP begin in childhood and cause people to lose their sight almost entirely over time.
That said, even if the front of your eye functions perfectly and you have a fantastic pair of eyeglasses or contact lenses, your vision will still be affected by RP. It’s important to keep in mind that, given that RP refers to a group of disorders, the degree to which people are affected is variable.
While some people may go blind, others have noticed that their vision loss stops at a certain point. RP tends to affect both eyes regardless of how severe it is.
What Are the Symptoms of Retinitis Pigmentosa?
There are several symptoms of RP that tend to show up at different stages of life. During childhood, the first symptom that usually occurs is a loss of night vision. Parents of small children may notice that their children seem to have trouble getting around the house at night if the lights are off or adjusting to dim light.
Over time, this process may gradually lead to night blindness. Sometimes, a person’s vision may be perfectly normal during the day, but they cannot see anything at night. For adults with RP, driving at night may become increasingly difficult and eventually impossible.
Another common symptom of RP is a gradual loss of peripheral vision. You might’ve heard this phenomenon referred to as “tunnel vision.” If you’re experiencing tunnel vision, you might bump into the things around you because you can’t see the objects below and beside you.
As RP progresses, it may lead to more serious symptoms like losing the ability to see color, being sensitive to bright light, experiencing twinkling or flashing light, losing central vision, or having low vision overall. Losing your central vision may make it hard to do tasks like reading or sewing.
What Causes Retinitis Pigmentosa?
RP is usually caused by mutations in the genes responsible for controlling the development of cells in the retina. The fact that RP is inherited means these gene mutations get passed down through family members, from parents to children. If you have a family history of RP, it’s important to consult your doctor.
Unfortunately, several different genes can cause RP, and there are also many ways those genes can be inherited. Working with a gene counselor can help someone with RP understand their likelihood of passing it on to their children.
Although it’s far less common, RP can sometimes also be caused by medicines, infections, or eye injuries.
How Is Retinitis Pigmentosa Diagnosed?
There are four main ways that RP is diagnosed, and this section will provide you with a brief overview of each diagnosis method. It’s important to note that if you think you or a loved one has any symptoms of RP, seeking medical attention is always a good idea.
Your ophthalmologist or another type of doctor may use one or many of the following diagnostic methods to discover the underlying cause of your symptoms.
Genetic Testing
Given that RP is a hereditary disease, genetic testing is a helpful diagnostic tool. With a sample of your blood and other tissues, they will look to see if you have any of the genes associated with the disease. This type of testing is usually done with a genetic counselor who can order and interpret the test and its results for you.
Knowing the specific disease that’s the cause of symptoms can be helpful because it can provide information about how the disease will progress and how other people in your family might be affected. Genetic testing is also important because the results can help you qualify to participate in a gene therapy clinical trial or to receive gene therapy.
Electroretinography
This is a type of test that measures how well your retina responds to light by measuring the electrical activity in your retina.
If you have to get an electroretinogram (ERG) test, then your healthcare provider will flash different lights in front of your eyes, which will measure your retina’s responsiveness.
Visual Field Testing
Visual field testing is a type of testing that doctors use to measure your peripheral vision. Given that RP can negatively affect your peripheral vision, this can be a helpful tool to determine if you have any blind spots developing and how severe they are if they are already there.
Optical Coherence Tomography
Optical coherence tomography, also referred to as OCT, is one method your doctor may use to take an extremely detailed picture of your retina. Using this picture, your doctor will be better able to diagnose RP and understand the extent to which your retinas have been affected.
Fundus Autofluorescence Imaging (FAF)
This is another type of imaging that your doctor may request. With fundus autofluorescence imaging, your doctor will take a picture of your retina using blue light.
How Can You Treat Retinitis Pigmentosa?
The wide range of experiences people with RP have means that there isn’t a one-size-fits-all treatment plan for it. That said, there are a few different treatment options that you can try.
In some instances, vitamin A is able to slow down the progression of certain types of RP. That being said, taking too much of this supplement can cause harm which is why it’s always a good idea to talk with your ophthalmologist before you start vitamin a supplementation for your eyes.
If you develop cataracts as a result of the form of RP that you have, surgery to treat them might be beneficial. There’s also a medicinal genetic therapy that can RP caused by a defect in the RPE65 gene, and scientists are working to develop more therapies to treat different varieties. In specific cases, someone with severe RP may be able to get a retinal prosthesis, also known as an artificial retina.
There are also several devices and low vision aids that people with RP can use to make the most of their vision. Lifestyle changes like wearing sunglasses and avoiding exposure to excessive light can also help protect your eyes.
Wrapping Up
Retinitis pigmentosa is the name of a series of diseases that lead to retinal degeneration and progressive loss of vision. These diseases are caused by genetic mutations and are passed down through families. In people with RP, the back of the eye (retina) will gradually break down over time.
Depending on the severity of the disease progression, RP can lead to loss of color vision, tunnel vision, or loss of vision entirely.
Genetic counseling and different forms of testing can help you understand the underlying cause of your RP. From there, there are several treatment and management strategies you can use to protect your eyes and preserve your vision.
Sources:
Retinitis Pigmentosa: Current Clinical Management and Emerging Therapies | NIH
UCSF Retinitis Pigmentosa Clinical Trials for 2024 | UCSF
Retinitis Pigmentosa Research Advance | Foundation Fighting Blindness