Retinitis, also called retinosis, encompasses a set of diseases that affect the retina, an important region of the back of the eye that contains cells responsible for capturing images. It causes symptoms such as gradual loss of vision and the ability to distinguish colors, and can even lead to blindness.
The main cause is retinitis pigmentosa, a degenerative disease that causes gradual loss of vision, most of the time, caused by a genetic and hereditary disease. In addition, other possible causes of retinitis may include infections, such as cytomegalovirus, herpes, measles, syphilis or fungi, trauma to the eyes and the toxic action of some drugs, such as chloroquine or chlorpromazine, for example.
Although there is no cure, it is possible to carry out the treatment of this disease, which depends on its cause and the severity of the injury, and may involve protection against solar radiation and supplementation of vitamin A and omega 3.
How to identify
Pigmentary retinitis affects the function of photoreceptor cells, called cones and rods, which capture images in color and in dark environments.
It can affect 1 or both eyes, and the main symptoms that can arise are:
- Blurred vision; Decreased or altered visual ability, especially in poorly lit environments; Night blindness; Loss of peripheral vision or change in visual field;
Vision loss can gradually worsen, at a rate that varies according to its cause, and can even lead to blindness in the affected eye, also called amaurosis. In addition, retinitis can occur at any age, from birth to adulthood, which varies according to its cause.
How to confirm
The test that detects retinitis is the bottom of the eye, performed by the ophthalmologist, who detects some dark pigments in the eyes, in the shape of a spider, known as spicules.
In addition, some tests that can help in the diagnosis are tests of vision, colors and visual field, examination of tomography of the eyes, electroretinography and retinography, for example.
Main causes
Pigmentary retinitis is mainly caused by inherited diseases, transmitted from parents to children, and this genetic inheritance can arise in 3 ways:
- Autosomal dominant: in which only one parent has to transmit for the child to be affected; Autosomal recessive: in which it is necessary for both parents to transmit the gene for the child to be affected; Linked to the X chromosome: transmitted by maternal genes, with women carrying the affected gene, but transmitting the disease, mainly, to male children.
In addition, this disease can result in a syndrome, which in addition to affecting the eyes, can compromise other organs and functions of the body, such as Usher syndrome.
Other types of retinitis
Retinitis can also be caused by some type of inflammation in the retina, such as infections, the use of medications and even blows to the eyes. As vision impairment in these cases is stable and controllable with treatment, this condition is also called pigmentary pseudo-retinitis.
Some of the main causes are:
- Infection with the cytomegalovirus virus, or CMV, which infects the eyes of people with some immunity impairment, such as AIDS patients, and its treatment is done with antivirals, such as Ganciclovir or Foscarnet, for example; Other virus infections, such as severe forms of herpes, measles, rubella and chicken pox, bacteria such as Treponema pallidum , which cause syphilis, parasites, such as Toxoplasma gondii , which causes toxoplasmosis and fungi, such as Candida. Use of toxic medications, such as Chloroquine, Chlorpromazine, Tamoxifen, Thioridazine and Indomethacin, for example, which are remedies that generate the need for ophthalmic monitoring during their use; Blows in the eyes, due to trauma or accident, which can compromise the function of the retina.
These types of retinitis usually affect only one eye.
How the treatment is done
Retinitis has no cure, however there are some treatments, guided by the ophthalmologist, that can help control and prevent the progression of the disease, such as supplementation of vitamin A, beta-carotene and omega-3.
It is also important to have a protection against exposure to light of short wavelengths, with the use of glasses with UV-A protection and B blockers, to avoid the acceleration of the disease.
Only in the case of infectious causes, it is possible to use medications such as antibiotics and antivirals, to cure the infection and decrease damage to the retina.
In addition, in the event that vision loss has already occurred, the ophthalmologist can guide aids such as magnifying glasses and computer tools, which can be useful to improve the quality of life of these people.
