It is a collection of inherited eye disorders involving the retina of the eye sensitive nerve layer light lining the back of the eye and causing a reduction or loss in the gradual visual ability.
Retinitis pigmentosa produced a selection of different hereditary retinal defects, which disturb the capacity of the retina to sense light.
Defects in the retina start in different areas of the eye’s outer layer.
One could be the rod cells of the retina, which is a kind of retinal cells that have been outside the central percentage of the retina that helps to conduct dim light and allow peripheral vision
Other might be the retinal cone cells, a type of retinal cells that have been in the middle of the retina that support to send color images and details
Another potential area could be the connection between the cells that make up the retina.
According to the genetic classification, the disease can occur as an isolated case in a family without some pathological history.
It could happen in many instances in the same family and a specific pattern of inheritance, such as autosomal dominant inheritance or recessive, or sex-linked passive form.
Common Symptoms
- The difficulty is seeing the light when it is low.
- A decrease in the visual field, either essential vision or peripheral.
- One difficulty reading print.
- Difficulty deciphering detailed images. One problem is seeing objects stumbling or tripping; usually resulting in clumsiness.
- Loss of central acuity, this is one of the most advanced stages of retinitis pigmentosa. The eyes lose the ability to see the details of things that are against the individual.
Diagnosis
- Visual acuity test – eye exam which measures vision ability at several distances.
- Ophthalmoscopy – a doctor, executes a complete inspection of the retina with a special amplifying glass.
- The refraction test.
- Ng defective test color determination.
- The examination of the retina.
- Ultrasound of the eye (ocular ultrasound).
Causes
Some medical experts consider that retinitis pigmentosa is a genetic disease and, therefore, is not caused by infections, trauma, injury, or any other external agent.
These genetic alterations cause the cells of the retina called photoreceptors (cones and rods) to work incorrectly, so that over time many of them degenerate and die, producing a progressive loss of vision.
Other theories suggest that this disease has an autoimmune, biochemical or metabolic cause; however, there is not enough evidence to prove it.
Retinitis pigmentosa can appear sporadically (in these sporadic cases, which are due to new mutations, affected people do not transmit the disease to their offspring), or be hereditary (being hereditary, it usually affects other members of the same family ).
Therefore, if a person gets diagnosed with this disease, it is recommended that an ophthalmologist evaluates the members of their family.
Within the hereditary forms we can distinguish three patterns of inheritance:
- Autosomal dominant pattern: The child who inherits one copy of one altered gene in each cell is prone to suffer from the condition
- Autosomal recessive pattern: The child inherits two copies of a mutated gene from their parents. But in these cases, they do not display any symptoms
- X-linked pattern: This happens when the altered copy of the gene is on the X chromosome. In such circumstances, males are prone to suffer from the condition, while females have to hold the mutation on both of their X chromosomes for the disease to arise
Treatment
Precise treatment will be determined by the medical constructed on:
- Age, health, and medical history.
- The progress of the illness.
- Tolerance for specific medications, procedures or therapies.
- Expectations for the course of the disease.
- The opinion or preference of the person concerned.
Unfortunately, so far, there is no a precise treatment for retinitis pigmentosa. But, protecting the retina of the eye using glasses with UV protection to can help deferral the onset of symptoms.
The patient with retinitis pigmentosa should handle with the sole purpose of improving their vision and life.
The correction of refractive errors matters how small, can be of great significance as increased personal view of a patient.
The use of goggles against the light has not proven beneficial, to stop the progression of the disease, but help to contrast the symptoms.
Moreover, although not shown that light has harmful effects for these patients, they advised not to look at the sunlight and instead, use ordinary sunglasses with UV filters.
It has promoted the use of sunscreens in the range of 550nm, but also without scientific evidence of benefits and other adverse psychological effects.
A better understanding of the disease by the patient, with full knowledge of the progression of it, based on regular making Electroretinography visual fields and can be helpful for the planning of the future life of the patient.
From the family point of view, it must also get a full understanding of the disease, its characteristics, and prognosis, so that the family will become an essential point of support for the patient.
Finally, as for the genetic management of patients with retinitis pigmentosa, the exact knowledge of the inheritance pattern is perhaps the most critical part, because genetic counseling will be a significant point of support and prevention of disease.