Retinitis Pigmentosa is a group of rare and inherited disorders, which can start in adolescence and can cause a gradual decline in a person’s vision.
What is RP?
A progressive order that can begin in adolescence and lead to blindness is retinitis pigmentosa (RP). It is actually a group of rare and inherited diseases that cause the degeneration of the retina, which is an important structure located in the back of the eye. With RP, the patients of board-certified retina specialists, Dr. Shawn Agee and Dr. John Sullivan at Southeastern Retina Specialists, have an issue with the retina capturing images from their visual field, which greatly impacts sight and perception. The disease is also affected by the death of photoreceptor cells (rods and cones) in the eyes. It’s estimated that around 100,000 people in the U.S. suffer from retinitis pigmentosa.
Retinitis pigmentosa comes in several forms, which include:
Leber’s congenital amaurosis
Causes and Symptoms
There are a number of causes of RP. Depending on whether rods or cones are involved from the beginning, this ultimately determines which symptoms will arise. Most commonly, the rods are initially affected. Since rods are largely concentrated in the retina’s outer portion, they are affected by dim light. Therefore, when rods degenerate, a patient’s night and peripheral vision are affected.
On the other hand, the cones are located centrally in the retina and play a role in seeing color and affect sharp central vision. So, when cones degenerate, a patient is less able to perceive color and has a loss of central vision.
With a genetic component to the disease, males are more frequently and adversely affected by the disease when he carries the familial X-linked RP trait. While females can also carry the gene, they are affected less frequently. Patients can have the disease as a result of a genetic mutation where one or both parents carry the gene. When genes mutate, the incorrect instructions are given to the rods or cones, which cause them to either make the wrong protein or the incorrect amount (too little or too much.) Since RP is a progressive disorder, it is common in adolescents and young adults and can lead to many patients being declared legally blind by age 40.
Common symptoms of RP are:
Decreased central vision
Decreased ability to determine color
Decreased peripheral vision
Once a patient exhibits any signs of RP or has a family history of the condition, an ophthalmologist can conduct a comprehensive eye exam to make a diagnosis. First, the eyes will be dilated to check the retina for any signs and symptoms of RP. In some cases, your doctor will place electrodes on the clear, front area of the eye (cornea) and around the eye. This is called electroretinogram. It’s painless and is used to measure how cells in the retina respond to light. A visual field test is also used where you’ll stare at a fixed point and gesture when you see an object appear in your side vision.
There’s also genetic testing available to make a determination of the probability of a parent passing the disease on to his or her child.
Treatment and Prognosis
There are several treatment options available for RP. These include:
Cataract surgery which can help improve vision, especially during the later stages of the disease.
Corticosteroids to prevent cystoid macular edema, which is a build-up of cyst-like areas of fluid in the central part of the retina, the macula.
Ciliary neurotrophic factor (CNTF) involves the surgical placement of cells into the eye.
Stem cell transplantation is where cells are derived from bone marrow or embryonic stem cells and used to replace damaged photoreceptor cells.
Although most patients with RP are legally blind by age 40, getting treatment early can greatly prolong vision and in some cases, prevent blindness altogether. Cataract surgery can improve vision for many patients, whereas medication use can prevent other symptoms and conditions from developing. CNTF has shown that patients can experience a retinal thickening, which can prevent further retinal degeneration. With cell transplantation, there have been promising results where vision has improved in some patients.
Patients need to be realistic with their prognosis since outcomes vary greatly among patients. Furthermore, many methods are just being studied and have only been used on small groups of patients. Their long-term effects aren’t yet fully understood.
Treat RP Today
There have been great strides in the treatment of retinitis pigmentosa and our office would love to share them with you. Our goal is to get you diagnosed and treated as soon as possible to provide you with the best possible prognosis. Our knowledgeable staff would love to hear from you, so give us a call today to schedule an appointment.