Hemeralopia (night blindness, night blindness) is a sharp deterioration in vision in low light conditions, at dusk and at night. The mechanisms of development of hemeralopia are based on disturbances in the formation and disintegration of the visual pigment rhodopsin in the rod cells of the retina, which plays an important role in the adaptation of vision to darkness.
The reasons
The cause of hemeralopia is beriberi or hypovitaminosis A, also B1 and PP. Symptomatic hemeralopia is observed in diseases of the retina and optic nerve. The process of restoration of visual purpura plays a role in the development of the disease.
There are congenital, symptomatic and essential hemeralopia. Congenital hemeralopia manifests itself in childhood and early adolescence, often has a family and hereditary character.
Symptoms
Weakening of vision and spatial orientation at dusk. Decrease in light sensitivity, violation of the process of dark adaptation, changes in the electroretinogram, narrowing of the visual fields, especially in colors. The diagnosis is made on the basis of complaints, the clinical picture, dark adaptation studies and electroretinography.
Diagnosis
The diagnosis is made on the basis of complaints, the clinical picture, dark adaptation studies and electroretinography.
Prevention
Prevention includes rational nutrition, prevention and timely treatment of eye diseases.