Retinitis pigmentosa (RP) is a collection of diseases of the retina that can cause sufferers to experience night blindness and visual disturbances that develop gradually, eventually leading to blindness.
The retina is a thin layer at the back of the eye that serves to capture light and convert it into a signal to be sent to the brain, so we can see.
In the retina, there are two types of photoreceptor cells that function to capture light, namely rods and cones. Rods are located at the edges of the retina, and their function is to help see in the dark. While cone cells function to help see in bright conditions, and most of these cells are located in the center of the retina.
In retinitis pigmentosa, there is a gradual death of photoreceptor cells, especially stem cells, caused by genetic disorders.
Types of Retinitis Pigmentosa
Retinitis pigmentosa is a rare condition and is estimated to occur in only 1 in 3,000–8,000 people worldwide. Although rare, retinitis pigmentosa is a major genetic cause of retinal disorders.
Based on the nature of inherited genetic disorders, retinitis pigmentosa can be divided into several types, namely:
In autosomal recessive cases, it takes a pair of faulty genes to cause retinitis pigmentosa. That means, a person can experience this condition only if he inherits 2 genes that carry the disease retinitis pigmentosa, namely one from the father and one from the mother.
Inbreeding is a factor that can increase the risk of developing autosomal recessive inherited retinitis pigmentosa.
Whereas in autosomal dominant, it only takes 1 gene that carries retinitis pigmentosa to cause this disease in a person. Patients with this type of retinitis pigmentosa have a 50% chance of passing the same disease on to their children.carrier), both male and female.
Women have a pair of XX chromosomes, and men have a pair of XY chromosomes. In this case, the disease-carrying gene is passed along with the X sex chromosome, either from the father or the mother.
Boys who get an X sex chromosome carrying retinitis pigmentosa will experience retinitis pigmentosa, while girls who get 1 sexual X chromosome that has a problem will have retinitis pigmentosa. carrier.
About 15–25% of retinitis pigmentosa can be inherited in an autosomal dominant manner, while 15–25% are inherited in an autosomal recessive manner, and 10-15% are inherited in an autosomal recessive manner. X-linked. While about 45-55% the rest occurs spontaneously without being inherited from parents.
How much vision is lost, at what age the symptoms begin to appear, and how quickly the symptoms worsen depend on the type of retinitis pigmentosa you have.
Of the three characteristics of the decline in retinitis pigmentosa above, X-linked is the most severe case. People with this type of retinitis pigmentosa will usually lose sight in the middle of the visual field in their 30s.
Meanwhile, autosomal dominant inherited retinitis pigmentosa is the mildest type of disease course. Complaints generally appear in their 40s, and sufferers' vision can last into their 50s to 60s.
Symptoms of Retinitis Pigmentosa
Symptoms of retinitis pigmentosa can vary. However, because most types of retinitis pigmentosa affect the stem cells that function to see in the dark, the most common symptoms are:
1. Night blindness (nyctalopia)
These symptoms most often occur early in the course of the disease and cause sufferers to frequently bump or trip over objects in the dark and unable to drive at night or when it is foggy.
2. Narrowing of the field of view (tunnel vision)
Narrowing of the visual field or visual disturbances at the edges of the visual fieldtunnel vision). Sufferers often complain of bumping into furniture or doorknobs, or having trouble seeing the ball when playing tennis or basketball.
3. Photopsia and photophobia
On photopsia, sufferers see flashes, sparkles, or flashes of light. While on photophobia, sufferers easily feel dazzled when looking at light.
Most complaints due to retinitis pigmentosa appear at the age of 10-40 years. These symptoms may worsen gradually over a matter of years, or they may worsen rapidly over a short period of time.
Sometimes people with retinitis pigmentosa also have other eye problems, such as cataracts, retinal swelling (macular edema), myopia (nearsightedness), hypermetropia (farsightedness), open-angle glaucoma, or keratoconus.
Retinitis Pigmentosa Diagnosis and Treatment
This condition requires an examination by an ophthalmologist. The ophthalmologist will perform a basic eye examination which includes a visual acuity test, color blindness test, pupillary reaction, an examination of the front of the eye, an examination of the visual field, eye pressure, and a retinal examination with a funduscopy.
To confirm the diagnosis, the ophthalmologist will perform the following investigations:
- Electroretinography (ERG), to examine the response of photoreceptor cells to light
- Optical coherence tomography (OCT), to check the condition of the retina
- Genetic testing, to determine whether there are abnormalities in the gene
There is no treatment that can cure retinitis pigmentosa or restore the vision that sufferers have lost due to this condition. Changes in diet and supplementation of vitamin A palmitate, DHA, lutein, and zeaxanthin may slow the progression of the disease.
However, the results of existing studies so far are still confusing and cannot provide a conclusion whether the above supplements are really useful or not in the treatment of retinitis pigmentosa.
If there are conditions such as cataracts or retinal swelling (macular edema), an ophthalmologist can provide treatment for each of these conditions, to help improve vision.
Patients with retinitis pigmentosa are advised to wear sunglasses when they are outside the home during the day, so that their eyes are protected from sun exposure. This is because excessive light exposure can accelerate the decline in vision power.
Actually, there is a way that can be done to restore the vision of people with retinitis pigmentosa, namely by implanting a device that can convert light into signals that can be sent to the brain. However, this tool is not yet available in Indonesia.
If you experience symptoms of retinitis pigmentosa, such as night blindness, gradual loss of vision, narrowing of your visual field, or frequent flashes of light, you should see an ophthalmologist. If it is true that you have retinitis pigmentosa, also check your child or sibling to an eye doctor to screen for this disease.
dr. Michael Kevin Robby Setyana