Everything you need to know aboutRP diseaseKnow
Retinitis Pigmentosa (RP) is a rare hereditary disease in whichthe retina of the eyeis gradually damaged, ultimately leading to blindness. If RP disease is suspected, your doctor will conduct various tests, such as visual field tests, to assess the extent of retinal damage. Specialized tests will also be performed to determine if you have night blindness or have lost your normal vision.
Symptoms of RP disease
The first symptoms of this disease usually appear in early childhood, and typically, both eyes are affected. Initial symptoms include poor vision at night and reduced field of vision, which gradually disrupts the light-sensitive cells responsible for night vision, making it increasingly difficult to see at night.
In the later stages of RP disease, only a small portion of central vision along with some peripheral vision will remain. It is very difficult to predict the extent of retinal damage in this disease; however, the doctor will determine the retina’s ability to provide vision through multiple tests. In some cases, patients are advised to avoid driving at night and only drive during the day in well-lit areas, as their vision will gradually deteriorate.
What causes RP disease?
RP disease affects the performance of light-sensitive cells in the back parts of the eye as a group of diseases, and the factors involved in the onset of this disease, except for the hereditary ones mentioned earlier, are largely unknown.
The visual system, or the eye, is associated with 32 different genes that possess genetic traits. If either of the parents has RP disease, there is a possibility that the disease may be passed on to their children, and there is also a chance that the disease could be transmitted through genes to future generations.
This means that an individual may develop the disease even without having a parent affected by RP. In fact, about 1% of people in a population are carriers of this disease.
Approximately 4,000 people worldwide suffer from this disease. If this hereditary trait is dominant, the symptoms are likely to appear in the person’s 40s. However, if it is recessive, symptoms are likely to manifest in the person’s 20s.
Treatment for RP disease
Currently, there is no cure for RP disease, but several companies are working on developingretinal implantsand other innovative treatment methods for this disease; however, these methods will only restore some visual abilities for individuals affected by RP disease. Certain tests and the use of these devices are only available in some European countries and the United States.
Argus Retinal Prosthesis System:
The Argus prosthesis medical products are designed for blind patients and individuals with RP disease and other retinal-related conditions.
The Argus system includes a tiny video camera embedded in a special pair of glasses. This camera wirelessly transmits electronic signals to an implant located in the retina. The implant uses this information to stimulate the remaining cells in the retina, sending visual information to the optic nerve.
The patient learns to interpret the received patterns to recognize the outlines of objects.
Researchers conducted a four-year study of the Argus retinal prosthesis system on 30 RP patients, all of whom gained the visual ability to open doors and windows and perform similar tasks with the system. Additionally, two of these patients were able to read short sentences, exceeding the researchers’ expectations. This ability was maintained for up to two years.
The Argus retinal prosthesis system was approved by the U.S. Food and Drug Administration in February 2012 and is used to treat individuals with RP. The cost of using this system is approximately $150,000, although some health insurance covers part of the expenses related to the device and implantation surgery.
Retina Implant:
Retina Implant is another medical device company that is producing retinal implants for patients with RP disease.
Alpha Implant:
The Alpha implant, a product of a German company, is a 3mm square silicon microchip implanted under the retina near the macula.
This implant contains 1,500 individual pixel cells, each comprising a light-sensitive photodiode, an amplifier, and an electrode for transferring electrical signals to the optic nerve. The pixel cells will replace the damaged natural receptors in the retina, and when light hits the photodiodes in the implant, they generate an electrical pulse and send it to the optic nerve and to the visual part of the brain.
Since the light-sensitive implant cannot replicate the complex visual perception process created by natural light receptors in the retina, patients using this implant cannot visualize objects with natural quality. However, they can still detect light sources and recognize nearby objects.
Clinical trial results conducted in February 2012 showed that patients with RP who underwent treatment with the Alpha implant were able to recognize faces and read signs on doors. The results from the company’s first human clinical trial published in 2010 indicated that some Alpha implant recipients could identify objects, recognize faces, read words, and see certain spots on the wall.
Retina implants have not yet received approval from the U.S. Food and Drug Administration; however, this company reported in December 2012 that based on the results from the trial of 36 RP patients who underwent implantation surgery, this product received market certification in Europe.
Electrical Stimulation Method:
According to representatives from Ecovision, a German equipment company established by Retina Implant, the use of Eye Stimulation Method (EST) can help preserve the vision of RP patients in the early and middle stages of the disease.
In a clinical trial involving 24 RP patients in early and middle stages who were treated with electrical stimulation, significant progress was observed. Researchers believe that electrical stimulation of the retina improves the performance of remaining retinal cells in RP patients.
Other treatments for RP disease:
Other potential treatment methods for RP disease include injectable capsules that may help preserve or prolong retinal function,Vitamin Aand other antioxidants.
Nutritional therapies aimed at reducing retinal damage and gene therapy are designed to introduce normal genes into retinal cells to replace defective and lost retinal cells.
As mentioned in the health section ofSelMagzearly diagnosis and treatment of RP disease can significantly help control and prevent its worsening. Therefore, if you notice any vision problems, consult a doctor promptly and seek to identify the cause.
