The first symptom that people suffering from retinitis pigmentosa (RP) experience is almost always night-blindness (poor eyesight in the dark). After this, the field of vision gets increasingly smaller. Usually the outer edges of the field of vision disappear and the tunnel that remains gradually narrows down (tunnel vision). Finally, the eyesight within this tunnel gets less clear.
Despite the fact that eye measurements can be really confrontational, it is still wise to visit an ophthalmologist every two years. The retina of someone suffering from Usher Syndrome is weak and it is important to timely discover and treat any other eye problems that have nothing to do with RP.
THE VISUAL SYSTEM
The eye, the optical nerve and the brains enable a person to visually perceive the surroundings.
The visual system has an optical part, a part in which an image is converted into electrical signals, a part for transferring these signals and a part to observe the image.
An object that we focus our eyes on is sharply imaged on the retina (retina) by the lens system of the eye. There, light has to be converted into electrical signals in order to be transmitted to the brain. This conversion takes place in specialized cells in the retina: the rods and the cones.
Actually, retinitis pigmentosa (RP) is not one single eye disease, but a collective name for a large group of hereditary retina disorders. Most people suffering from RP will become night-blind, develop tunnel vision and their eyesight deteriorates.
The name retinitis pigmentosa refers to the accumulation of pigment in the retina. With RP the light-sensitive cells, the photoreceptors, in the retina slowly die. These are the rods and the cones. The rods are found in the outer part of the retina and most cones are found in the central part.
About 4000 people in the Netherlands suffer from retinitis pigmentosa. 800 to 1000 people of this group suffer from Usher Syndrome (RP with loss of hearing).
THE EXAMINATION AT THE OPHTHALMOLOGIST
An ophthalmologist can quite easily confirm the diagnosis of Usher Syndrome by looking at the retina with an otoscope and by doing a field of vision test.
In case of retinitis pigmentosa the ERG test particularly deviates at an early stage (the part registering the functioning of the rods).
Do you want to know more about the tests done by the ophthalmologist?
ADDITIONAL EYE SYMPTOMS
Although the ophthalmologist cannot remove or cure the RP, he or she may sometimes be able to help. As the eyes are more vulnerable than ‘healthy’ eyes because of the RP, there is an increased chance of short-sightedness, cataract, malcula oedema and glaucoma. By regularly testing the eyes, any other eye problems can timely be discovered and treated, if possible.
Cataract is not a symptom of RP, but a consequence. As the retina deteriorates because of RP, cataract often occurs at a young age. You are more bothered by stray light and colours become duller. Sometimes you have a feeling that you are looking through mist. Cataract surgery can help and remedy the symptoms. It is difficult to estimate beforehand to what extent cataract surgery will improve the eyesight. Most symptoms of cataract are symptoms that also go together with deterioration because of RP.
THE COURSE OF DECLINE
Most people suffering from Usher Syndrome experience slow, gradual deterioration. Sometimes there is a period in which the disease seems to be stable to be followed again by a period of accelerated deterioration. The eyesight can remain reasonably well until a high age. About 25% of the patients retains a sharp vision in the central part.
The simultaneous ability to see details (tunnel vision) and not being able to see large obstacles (observation of the surroundings) is sometimes hard to understand for other people. It is good to inform family and colleagues about the disorder. This leads to a better understanding in general daily functioning.
IS THERE ANY TREATMENT?
At this moment there is no effective treatment for Usher Syndrome yet. A DNA test can discover changes in the genes (mutations). This DNA test can be useful for any gene therapy or RNA therapy in the near future.
Various research institutes all over the world are very busy finding solutions for all types of Usher Syndrome. The first clinical trials have already been started for some types and mutations of Usher Syndrome.
There are many (innovative) solutions and tools that can facilitate mobility, independence and information. There are techniques, tools, useful apps and many tips and tricks.
WHAT CAN YOU DO YOURSELF?
There is no treatment for retinitis pigmentosa yet, but you can do a number of things to keep your eyes healthy as long as possible. Of course, a healthy lifestyle with a varied diet is always good for the eyes. This also holds for sufficient exercise. Intensive use of the eyes is tiring for people with poor eyesight, but it is not harmful. Smoking is harmful to the eyes, because nicotine and other components of the cigarette can narrow down the blood vessels in the retina. This leads to less oxygen and more accumulation of toxic waste products in the retina.