SYMPTOMS OF RETINITIS PIGMENTOSA
The main symptoms of Retinitis pigmentosa are:
- Nyctalopia: includes poor night vision and poor adaptation to darkness or changing from light to darkness, which in many cases presents with dyscromatopsia, poor vision of colours.
- Photophobia: abnormal intolerance to light.
- Progressive loss of visual field until left with tunnel vision
Photoreceptors are the cells of the retina, there are two types: cones and rods. They have different functions and distribution in the retina.
Rods: the cells we use for night vision. Contain a visual pigment called Rhodopsin, which enables us to see shades of grey or blue colours. These cells are stimulated under low light intensity.
Rods are found in the periphery of the retina.
Cones: cells stimulated under high light intensity. They contain visual pigments that allow us to see colour. These cells provide higher visual acuity. Cones are scarce in the periphery of the cornea, its highest concentration is in the macula. This is why they provide greater visual acuity.
Hereditary diseases of the retina may affect:
- the macula to a greater or lesser extent
- mixed dystrophies of rods and cones
The reason for this is that there are many genes involved and among those genes there are multiple gene mutations that can cause this type of pathology.
Even within a family and with the same known gene mutation patients evolve in different ways due to environmental factors that have a direct effect on the gene.
The age at which the retinitis pigmentosa onsets, as well as the expression of the gene and its evolution varies significantly from one patient to another, making it very difficult to predict the development of this pathology.
Usually retinitis pigmentosa evolves to a loss of visual field preserving the ten degrees of central vision till very advances stages of the disease.
Doctor Beatriz Fernández-Vega explains in this video the causes, symptoms and treatments of this pathology.
CAUSES OF RETINITIS PIGMENTOSA
The basis of the disease is the existence of a genetic mutation that results in a malfunctioning of a protein involved in visual function. Subsequently, there is a progressive degeneration of visual cells followed by their death.
TREATMENT OF RETINITIS PIGMENTOSA
Currently, treatment for retinitis pigmentosa is undergoing clinical trials. There is no medical or surgical treatment for this pathology, but there are many lines of research.
Some of the clinical trials carried out for this disease are subsidised through the Asociación de Retinosis Pigmentaria (Retinitis Pigmentosa Association).
Treatments currently in experimental stage are: implantation of stem cells, transplantation of cells from the pigment epithelium, implantation of neuroprotectors and implantation of Brimonidine and gene therapy.