Hemeralopia, (Night Blindness, Night Blindness)

Hemeralopia, also known as night blindness or night blindness, is a twilight vision disorder that results in decreased vision and spatial awareness in low light conditions. This disease can be either congenital or acquired.

The causes of congenital hemeralopia are not fully understood. However, essential hemeralopia is usually associated with a deficiency of vitamins A, B2 and PP caused by vitamin deficiency or hypovitaminosis.

Symptomatic hemeralopia, in turn, is associated with diseases of the retina and optic nerve, which leads to disruption of the recovery process of visual purpura.

The main symptom of hemeralopia is weakened vision and spatial orientation at dusk, as well as decreased light sensitivity. In this case, there is a disruption in the process of dark adaptation, changes in the electroretinogram and a narrowing of the visual fields, especially color ones.

To diagnose hemeralopia, patient complaints, clinical picture, dark adaptation and electroretinography studies are used.

At the moment, congenital hemeralopia cannot be treated. However, with essential hemeralopia, you can take vitamin A orally, for adults 50,000-100,000 IU/day, for children from 1000 to 5000 IU/day, as well as riboflavin up to 0.02 g/day. For symptomatic hemeralopia, treatment is aimed at the underlying disease.

The prognosis for congenital hemeralopia is poor and is often accompanied by persistent decreased vision. However, with essential hemeralopia, the prognosis is favorable, provided proper treatment, and with symptomatic hemeralopia, the prognosis depends on the course and outcome of the underlying disease.