Retinitis Pigmentosa (RP): Causes, Symptoms, Treatments, and More.
Last updated: June 24, 2022
Retinitis Pigmentosa (RP) describes a group of eye diseases that result in retinal degeneration causing vision loss due to a decreased ability to respond to light. Although rare, Retinitis Pigmentosa is one of the most common hereditary diseases of the eye, affecting roughly 1 in 4,000 people globally.
Symptoms of RP include night vision loss, decreased peripheral vision, and side vision loss. The loss of peripheral vision may also lead to tunnel vision, which denotes the ability to see only straight ahead. Vision loss related to RP is slow, with the specific rate of deterioration depending largely on the genetic makeup of the condition. Although RP cannot be cured, there are available treatment options, as well as assistive technologies that can help to enhance remaining vision. Read on to learn more about RP, including causes, diagnosis, and treatments.
What is Retinitis Pigmentosa?
Retinitis Pigmentosa is a group of rare, inherited eye disorders that involve retinal degeneration. The ICD-10 Diagnosis Code for Retinitis Pigmentosa (RP) is H35.52. Common symptoms of the condition include difficulty with vision at night and the loss of peripheral vision.
Each Retinitis Pigmentosa disorder affects how the retina responds to light. There are two types of photoreceptor cells in the retina: rods that detect dim light, and cones that detect light and color. Most forms of RP begin with the degeneration of retinal rods, which thereby leads to night vision loss.
The retina is a light-sensitive tissue found at the back of the eye and is made up of millions of light-sensitive cells called ‘photoreceptors’. When damage to these photoreceptor cells occurs, the retina is unable to function properly and results in loss of vision.
Prevalence of Retinitis Pigmentosa
Although rare, Retinitis Pigmentosa is one of the most common hereditary diseases of the eye. It is generally estimated that RP affects roughly 1 in 4,000 people, both in the United States and worldwide.
Considering a global population of 7.8 billion, an estimated 1.77 to 2.35 million people around the world are affected by an RP-related disorder.
Retinitis Pigmentosa (RP) vs Retinal Dystrophy (RD)
Retinitis Pigmentosa is the most common form of Retinal Dystrophy. Retinal Dystrophy (RD) refers to chronic and progressive vision loss. Like RP, RD addresses the degeneration of retinal tissue, however, RD can be genetic or spontaneous in nature (i.e., disease or malnutrition).
Retinal Dystrophy disorders can be passed on from generation to generation via three different types of inheritance: dominant inheritance, recessive inheritance, and inheritance linked to the x chromosome.
RP can be transmitted through any of the three inheritance types, depending on the gene. Mutations in one of more than 50 genes can be responsible for causing the disease. RP starts with the degeneration of rod and cone cells in the retina, leading to night blindness and tunnel vision.
Symptoms of Retinitis Pigmentosa
Symptoms of RP often begin in childhood with slow, but progressive vision loss. The type of vision loss and the speed at which vision loss occurs will vary from person to person, depending on their specific disorder. The condition does not usually cause total blindness despite vision impairment. Read on for more information on the common symptoms of RP.
Loss of Night Vision
Retinitis Pigmentosa may cause night blindness, which makes it hard to see in low light. People with RP may have trouble seeing in low-light environments, such as movie theaters or other dim rooms. People with the condition may have trouble with their eyes adjusting to the darkness. Driving in the evening or at night can be difficult for people with this condition. However, many people with RP can experience normal vision during the day or in situations with high levels of light.
Loss of Central Vision
In advanced cases, people with RP can experience loss of their central vision. Central vision is the core visual field when a person looks straight ahead. When loss of central vision occurs, the person may have difficulty in carrying out detailed tasks like reading, writing, or threading a needle.
Gradual Loss of Peripheral Vision
People with RP may experience loss of peripheral (side) vision. This means they have trouble seeing things on the sides when looking straight ahead, resulting in tunnel vision. Loss of peripheral vision can cause someone to bump into things due to decreased ability to navigate while walking.
People with Retinitis Pigmentosa can have trouble seeing colors. They may experience some form of color blindness and find it hard to differentiate colors.
People with RP may develop an aversion to bright light or glare, also known as photophobia.
Causes of Retinitis Pigmentosa
Parents can pass the defective genes on to their children in three different ways: autosomal recessive RP, autosomal dominant RP, or x-linked RP inheritance.
Autosomal Recessive RP
The National Human Genome Research Institute says that most cases are the result of recessive genes. In a recessive condition, each parent possesses one defective copy and one normal copy of the gene responsible for the condition. Due to having only one copy of the defective gene, the parents are both asymptomatic. However, when a child inherits two defective copies of the gene – one from each parent – they will develop the relevant RP disorder. There is a 25% chance of a child in the family being affected.
Autosomal Dominant RP
This form of Retinitis Pigmentosa requires only one copy of the defective gene, because it is dominant. A parent with a dominant RP gene has a 50% chance of transmitting it to the child, and the child will develop the relevant RP condition.
X-Linked Retinitis Pigmentosa (XLRP) inheritance
In about 10% of RP cases, the defective gene is passed down from the mother to her children resulting in X-Linked RP (XLRP). Since females have two X chromosomes, the effect of a mutation on one X chromosome is canceled by the normal gene on the other X chromosome.
Retinitis Pigmentosa is a genetic condition, passed down from generation to generation. RP is not the result of infections, injuries, or other external causes. Mutations in more than 50 different genes have been linked to the condition.
If the mother is a carrier for an x-linked disorder, there is a 50% chance of having a son with the disorder and a 50% chance of having a daughter who is a carrier.
Does Retinitis Pigmentosa skip a generation?
Even though Retinitis Pigmentosa is an inherited disorder, it can skip generations. If a person has any family member with a retinal disorder, it is generally recommended for the person to see an optometrist.
Can you get Retinitis Pigmentosa at any age?
Yes, the age of onset may range from early childhood (usually around age 10) to adulthood (anywhere from age 20 to 40).
Diagnosis of Retinitis Pigmentosa
It is important to see a professional eye doctor if you have difficulty with your vision in dim light or at night. In addition, if you find yourself experiencing tunnel vision, you should consult a professional. An eye doctor will be able to tell you if you have Retinitis Pigmentosa through testing, including genetic testing and visual field testing.
Genetic testing involves taking a DNA sample and examining it for the presence of mutations in any gene related to vision loss. Genetic testing uses a technique called DNA sequencing, where a machine “reads” your genetic makeup and will identify mutated genes. Most genetic testing will evaluate hundreds of genes that are known to be related to inherited retinal disorders.
Genetic testing can also help determine the progression of the disease and whether gene therapy may an option for you.
Electroretinography measures the electrical responses of different types of cells in the retina including photoreceptors (rods and cones), inner retinal cells (amacrine and bipolar), and ganglion cells. Electrodes are placed on the cornea or on the skin beneath the eye to check the retinal responses. It will determine the electrical activity of the retina in response to a light stimulus.
Visual Field Testing
Visual field testing can also be useful for diagnosing Retinitis Pigmentosa. This testing will measure your peripheral vision, identify how much of your surroundings you can visualize, and pinpoint any defects in your peripheral vision related to Retinitis Pigmentosa.
An ophthalmoscope is conducted using eye drops to dilate the pupil and a tool to inspect the retina. If a person has Retinitis Pigmentosa, it will be evident through the appearance of specific dark spots on the retina.
Treatments for Retinitis Pigmentosa
Although currently there is no cure for Retinitis Pigmentosa, there are several options to reduce the progression of vision loss and in some cases, even restore lost sight. Speak to your doctor to see which treatment may be right for you.
In severe cases of RP, there may be swelling of the retina. This is known as Macular Edema and can result in low vision. Acetazolamide is a medication that can help reduce swelling and improve vision.
People who have critical vision loss due to RP can find relief with retinal implants like the Argus II retinal implant. The Argus II Retinal Implant may provide useful vision to blind individuals severely impacted by RP.
Gene therapy can be used to insert healthy genes into the retina and improve vision. Read more for recent developments in research and clinical trials for gene therapy.
Vitamin A Palmitate
The American Academy of Ophthalmology suggests that vitamin A palmitate can help people with RP to slow progressive vision loss. However, research is preliminary and vitamin A can be harmful in large doses. Speak to your doctor to see if vitamin A supplementation may be a solution for you.
People with low vision due to Retinitis Pigmentosa can leverage their remaining sight through low vision aids, ultimately improving their vision. For example, eSight’s low vision eyewear device has helped dozens of people with RP to improve their vision.
eSight’s Award-Winning Assistive Technology
eSight is a low vision assistive eyewear device that stimulates synaptic activity from the remaining photoreceptor function of the user’s eyes to improve vision. Using a cutting-edge camera, smart algorithms, and high-resolution screens, eSight’s assistive technology can provide the brain with increased visual information to naturally compensate for gaps in the user’s field of view. As a result, eSight makes clearer vision possible, resulting in an enhanced vision of up to 7 lines on an optometrist’s eye chart.
eSight Users with Retinitis Pigmentosa
Many eSight users have been able to see their family’s faces for the first time in decades, resume their hobbies and jobs, and regain confidence in their daily lives. While there are successful eSight users with Retinitis Pigmentosa, many Retinitis Pigmentosa patients are not suitable candidates for the device. Users such as Larry Kupner, a blind father and veteran, who lives with Retinitis Pigmentosa has been able to find success with using the device. Using eSight, he was able to see his family’s faces in detail for the first time in 10 years and now uses his enhanced vision to enjoy exploring and fishing in the great outdoors. Despite being legally blind without assistive tech, he can read with an astounding 20/40 visual acuity using eSight.
We recommend that if you have been diagnosed with Retinitis Pigmentosa and find magnification helpful to contact one of our eSight specialists to determine if you are a suitable candidate for eSight.
What is the ICD-10 code for Retinitis Pigmentosa?
The ICD-10 code for Retinitis Pigmentosa is H35.52.
Is Retinitis Pigmentosa hereditary?
Yes, Retinitis Pigmentosa describes a group of hereditary retinal disorders that can be passed from generation to generation. It may be inherited through autosomal recessive, autosomal dominant, or X-linked genes.
What is the age of onset for Retinitis Pigmentosa?
The onset of Retinitis Pigmentosa usually begins in childhood and can be identified in someone as young as 10 years old. However, for some people, the symptoms may not be evident until much later in adulthood, including in adults who are in their mid-20s to 40s.
How common is Retinitis Pigmentosa?
Retinitis Pigmentosa is one of the most common hereditary eye disorders, as it affects 1 in 4,000 people globally.
Who is most likely to get Retinitis Pigmentosa?
Since the condition is hereditary, Retinitis Pigmentosa can be transmitted from generation to generation. Sometimes, even if parents do not have the condition, they may be carriers and thus have children with RP.
Is there a cure for Retinitis Pigmentosa?
There is no cure for Retinitis Pigmentosa at the moment. However, there are various ways to reduce loss of vision and improve sight. Treatment options may include gene therapy, retinal implants, glasses, or low vision assistive devices like eSight.
What does someone with Retinitis Pigmentosa see?
Someone with Retinitis Pigmentosa will experience a gradual loss of vision. Symptoms usually begin with difficulty seeing at night, loss of peripheral vision, and color blindness.
How fast does Retinitis Pigmentosa progress?
The progress of Retinitis Pigmentosa varies from person to person. For instance, some people with RP retain some vision even at 80, while others may lose vision entirely by the time they are in their 30s.
Does Retinitis Pigmentosa get worse over time?
Since RP is a progressive disorder of the eye, it is likely to continue to get worse over time. It is important to see an eye specialist in the early stages to adopt preventive measures.
Does Retinitis Pigmentosa lead to blindness?
Although the majority of people with Retinitis Pigmentosa retain some form of vision, rarely, people with the condition may become blind.
Can Retinitis Pigmentosa be prevented?
Since Retinitis Pigmentosa is a hereditary condition, it cannot be prevented. However, its effects can be mitigated with proper management of the condition.