How and why is the disease manifested by night blindness?

The ability of a person to see well is determined by the good functioning of all eye structures, their proper size and shape, as well as the constant supply of essential nutrients and oxygen.If violations of at least one of the conditions, temporary or permanent nature, the quality of visual perception varies. And, as a rule, for the worse.

The human eye has the ability to adapt to any lighting conditions. However, for some reasons, this ability can be disrupted, and a person begins to see badly in the twilight or darkness.In this case, they speak of a disease called "night blindness".

Definition of disease

Chicken blindness (gemeralopia) affects the eyes with a decrease in the number of retinal cells that respond directly to twilight vision.

There are two types of photosensitive cells on the retina: cones and rods. The cones are necessary for good vision under bright light, and wands - in twilight conditions.

For normal vision, the eye needs much more rods than cones, since the situation of insufficient illumination occurs in life more often. Accordingly, the retina contains 7 million. cones and 115 million. chopsticks.

If the number of rods is reduced or their functionality is impaired, a person develops night blindness.The main cause of the disease is the decrease in the number of rhodopsin (visual pigment), which is the main condition for the good work of rod-shaped cells.

Types and Classifications

There are several types of disease, due to various etiological factors:

• Congenital.Disease is a hereditary pathology and can be transmitted to the child by one of the parents;
• Symptomatic. The disease occurs as a result of the development of other eye pathologies and manifests itself as their symptom;
• Essential(functional). The main reason for the development of the disease is a lack of vitamins, which leads to disturbances in metabolic processes. If such a phenomenon lasts long enough, the consequences become irreversible.

The internal reserves in the body of vitamin A, necessary for the synthesis of rhodopsin, usually last for a maximum of a year. Therefore, with the initial signs of diminishing vision, it is recommended to visit a doctor.

Causes

Different types of night blindness have different etiological factors:

• Congenitalthe disease occurs when there is a genetic mutation that does not lead to the appearance of severe congenital malformations. With such a disease a person can live with a minimum of restrictions. Therefore, a fetus with such an anomaly is not "rejected" by the body by spontaneous miscarriage. Characteristic is a concomitant gene mutation, which determines the development of hereditary pigment retinitis or Asher's disease;
• Symptomaticnight blindness has a number of etiological factors: myopia above -6, pigmentary degeneration of the retina, optic nerve atrophy, glaucoma, chorioretinitis, deposition of iron salts (siderosis);
• Essentialnight blindness is a consequence of a lack or disrupted assimilation of vitamins PP, A, B2. Such conditions can occur with malnutrition, anemia, starvation, liver diseases or digestive tract organs, transferred chickenpox or rubella, any intoxication (alcoholic, medicamentous, infectious, poisoning with poisonous chemicals), exposure to bright light is prolonged time.

  Vitamins of group B

The danger of an essential variety of disease in the gradual depletion of stocks in the body of vitamin A, which can be consumed within 2 years. And in the absence of an adequate response to a decrease in vision at dusk, irreversible changes in the functioning of the eyes occur.

Symptoms

The degree of symptoms may vary depending on the form of the disease, but the main symptoms of night blindness in humans include:

• Reduced visual perception in poor lighting conditions(at night, at dusk, in a dark room);
• Bad adaptation when changing the intensity of lighting: as when moving from a light section to a dark one, and vice versa;
• Narrowing of the fields of vision in low light conditions(tunnel vision);
• There is a need for more vivid illumination for reading and writing, which, against a background of normal vision in the twilight, is the initial sign of hemeralopia;
• Reducing the perception of yellow and blue in the twilight, and as a result, visual impairment in the form of fogging the image.

All these violations in childhood are the impetus to various violations of the mental plane.

Possible complications

The consequences of inadequate or untimely treatment of a symptomatic or essential form differ depending on the cause that provoked them:

• With symptomatic hemeralopiathe severity of complications depends on the underlying disease: with glaucoma this can be a significant reduction in vision and even complete blindness, with retinal dystrophy and optic atrophy all depends on the state of the eye at the initial stage treatment;
• With essential hemeralopiaThe severity of the negative consequences is directly dependent on the stage of diagnosing the disease. Timely and adequate treatment can completely eliminate negative manifestations and restore sight.

With hemorrhagia of any type, a pathological fear of the dark can develop, often transforming into phobias, mental disorders, obsessive-compulsive states.

Diagnostics

With the initial symptoms of diminishing vision, you need to get expert advice from a specialist. The ophthalmologist conducts traditional studies: visometry and ophthalmoscopy. However, the final diagnosis can be established after additional studies:

• Electroretinography- examination of the retina by recording electrical potentials, which are a response to light stimulation;
• Tonometry- research allows to determine IOP, the volume of intraocular fluid, the coefficient of its outflow;

  Carrying out tonometry according to Maklakov

• Refractometry- determines the ratio of the refractive force in the optical system of the eye and its correspondence to the longitudinal axis of the eyeball, provided that the accommodation is at rest;
• Biomicroscopy- allows to conduct microscopy of the main eye structures: anterior chamber, cornea, iris, lens, vitreous. With the use of the Goldman lens, examination of the fundus is possible;
• OCT (optical coherence tomography)- scanning the back of the eye to determine the parameters of the DZN, the condition and thickness of the layers of the retina.

  Conducting biomicroscopy of the eye

If necessary, a comprehensive examination is supplemented by consultations of the endocrinologist, gastroenterologist, and others. narrow-profile specialists.

Treatment

Therapeutic tactics in the treatment of night blindness completely depends on the form of the pathological condition revealed after the diagnostic measures.

Medicines

PThe principles of treating congenital and essential forms of the disease are the same, but their effectiveness varies radically.If congenital hemeralopia is practically incurable, causing a permanent decrease in vision, then the essential form of the pathological condition, the lack of vitamins is easily replenished by synthetic means. In addition to vitamin therapy, a special diet of foods with a high content of essential vitamins (A, PP, B2) is recommended:

• Greenery(parsley, dill, spinach, celery, young nettle);
• Leaf salad;
• Liver of cod (take in raw form on small pieces);
• Yolk eggs, cheese, butter, milk;
• Cabbage, tomatoes, carrots, green onions and green peas, corn;
• Blueberries, cherries, gooseberries, apricots, peaches, blackberries.

  Products containing vitamin A

These foods or dishes from them should be present in the diet constantly, but with the disease they are not able to provide the right level of vitamin content, so the intake of vitamin complexes is mandatory in any form disease.

In addition, in order to eliminate the excessive effect on photoreceptors, it is necessary to avoid bright illumination in any manifestations, and also wear glasses in the evening, even if there is an easy myopia.

Surgically

With symptomatic hemorrhagia, the main direction of treatment is the elimination of the underlying disease, which occurs in a number of cases with the use of surgical methods:

• Refractive surgery: lens replacement, scleroplasty, etc. ;
• Laser correction of myopia;
• Antiglaucomatous surgery: trabeculectomy, trabeculotomy, iridectomy, cyclo cryocoagulation;
• Phacoemulsification of cataract;
• Laser coagulationPretinal detachment.

  Laser Coagulation Procedure

The effectiveness of treatment of hemorrhagia completely depends on the success of eliminating the underlying disease.

Folk remedies

The use of folk remedies is a necessary supplement to the main treatment, since it helps to restore the balance of necessary substances in the body and, in particular, in the eye structures:

• Fish oil in any form is taken three times a day according to the recommended by the doctor scheme;
• All kinds of liver should be present in the diet in any form, even cheese;
• Boil a large amount of the liver and make an "inhalation" for the eyes, but steam should not be too hot. Such inhalations for treatment require a maximum of three. Cooked liver should be eaten for 2 weeks;
• Introduce in the diet millet porridge, and use it constantly;
• Mix dill and carrot juice (1: 5), use every morning for 140-150 ml;
• Grate the carrots, 3 tbsp. l. cook in 1 liter of water or milk until cooked, take a filtered decoction of 70 ml per night;
• Take a mixture of equal portions of herbs(cranberries, blackberries, primrose, viburnum, raspberries, lemon balm, rhizome of snake mountaineer), brew for 1 hour. l. raw 1/3 l of boiling water and insist 60 min. The filtered infusion takes 100 ml three times a day;
• Make a rice broth(1 tbsp. l. cereals for a glass of water), take 70 ml per night.

Although most folk remedies do not pose a health hazard, nevertheless, consultation the doctor will be superfluous, considering that in the treatment of night blindness many recipes are designed for a long application.

Prevention

In the absence of hereditary factors, the development of the disease can be prevented by the following preventive measures:

• Protect eyes from strong light sources:headlights for cars, neon signs and lamps, as well as direct UV rays;
• Adhere to the principles of healthy eating, preferring natural products and home-cooked dishes ready for consumption;
• Organize a workplace with properly selected lighting and observing optimal distances;
• In due time to treat the revealed eye pathologies and diseases of a general character;
• Regularly undergo preventive medical examinations.

Video

conclusions

Chicken blindness, acquired due to systemic (or eye) diseases or due to malnutrition,with timely and adequate treatment has a good chance of a successful cure.

The congenital form of hemeralopia is practically incurable, but in order to prevent progression, it must be under the constant supervision of a specialist.

And in any form, the principles of healthy eating (with a rich diet of vitamins) can have a positive effect on the course of the disease.And preventive measures can significantly reduce the risk of the onset and progression of the disease.