Visual acuity treatment. Visual impairment. Oculomotor muscles and nerves

Decreased visual acuity

Visual perception of various images allows a person to receive maximum information, which is why it is so important to monitor visual acuity and health visual organs. Timely appeal for qualified help will help solve the problems that have arisen.

Causes of decreased visual acuity (visual impairment)

There are many various reasons affecting visual acuity and its decline. Let's look at the most basic of them.

Visual impairment can occur due to diseases of the retina. This may be a detachment or rupture of the retina, vitreous detachment, macular degeneration, diabetic retinopathy. Vision decreases with cataracts, when the lens of the eye suffers.

Eye injuries of various etiologies, diseases associated with the cornea (cataract, keratitis and ulcerative lesions), also lead to vision impairment. Strabismus, caused by damage to brain cells, often causes vision loss.

Change hormonal balance in the body leads to a decrease in the ability to see well

Diseases such as pituitary adenoma and diseases associated with normal functioning thyroid gland, can reduce visual acuity by an order of magnitude. Similar symptom may be caused by diseases of the spine, be a consequence of sexually transmitted and various infectious diseases. Vision deteriorates with general fatigue, due to long work at the computer or reading for a long time.

Methods for correcting decreased visual acuity

A sudden deterioration in vision or a decrease in its acuity is a reason to consult an ophthalmologist. To conduct a full-fledged, high-quality diagnosis, he will definitely consult with other specialists, for example, schedule a visit to an endocrinologist.

Some vision problems require immediate treatment. This could be head and eye injuries, retinal rupture, etc.

Not all diseases that cause decreased visual acuity can be treated drug therapy. In such cases, surgical intervention is resorted to. An example of this is eye surgery to diagnose cataracts. By using medicines it is impossible to restore transparency to a lens that has become clouded due to disease, so surgery to replace it will be the only way restore vision.

Conservatively, vision can be improved if its impairment is associated with problems in endocrine system. When normalizing hormonal levels With the help of medications, visual acuity improves. Sometimes even in this case it is impossible to do without surgical intervention. Doctors may insist on removing part of the pituitary gland.

Decreased visual acuity due to age-related changes in the body or with prolonged visual stress, it is corrected with the help of therapy, including eye exercises, optimization of the work and rest regime for the eyes, taking special vitamin preparations.

Folk remedies for decreased visual acuity (visual impairment)

Aloe can be an excellent way to improve vision. To prepare it you need to pick fresh leaves plants weighing about 0.5 kg, wrap them in foil and place them in the refrigerator for a couple of weeks. Then the spines are cut off from the leaves using a razor and washed in clean water and scroll through a meat grinder. Add 0.5 kg of honey and half a liter of Cahors to the resulting mass and mix thoroughly. The product is ready! Store it in the refrigerator, and take 1 tbsp. spoon with warm water.

A medicine prepared from nettle can have a good effect. The infusion is prepared as follows: 1 tbsp. A spoonful of finely chopped nettle is mixed with 1 cup of boiling water.

The infusion settles for an hour, then filters. Take it 3 times a day, 1/3 cup. It is useful to add nettle to soups.

Hawthorn helps with myopia, the dried and ground berries of which are mixed with natural honey in equal parts. Dose medicinal mixture 3 tbsp. spoons per day.

The following recipe is also offered: parsley root, passed through a meat grinder, is mixed with lemon juice and honey. The number of components can be changed at your discretion. This mixture is useful when taken 1 teaspoon one and a half hours before meals.

These are well suited for correcting visual acuity. folk remedies: eat sprouted wheat in your diet, drink juices from blueberries, parsley, nettles, carrots.

Facilities traditional medicine, of course, provide significant assistance in restoring visual acuity, but one must remember that their use is only an addition to the treatment prescribed by the doctor.

Rapidly developing decrease in visual acuity in young people is most often a consequence of retrobulbar neuropathy optic nerve, or retrobulbar neuritis, occurring more often on one side, sometimes on both sides, simultaneously or sequentially.

Clinical manifestations. The patient first notes the appearance of fog, a veil before the eye, and sometimes pain in the depths of the orbit. The decrease in visual acuity usually increases over several hours or several days, and can reach 0.1-0.2; Complete blindness rarely occurs. Pupil on the side pathological process may be dilated, its reaction to light is reduced. The cause of this form of pathology is often demyelination of the optic nerve fibers. Due to the retrobulbar localization of the process, there may be no deviations from the norm in the fundus, but often ophthalmoscopy reveals signs of papillitis: hyperemia and protrusion (elevation) of the optic nerve head in vitreous, some blurring of its borders is possible, sometimes peripapillary hemorrhages; however, significant hyperemia of the retinal veins does not occur. The latter circumstance helps to distinguish papillitis from congestive optic disc during ophthalmoscopy. The main criterion for their differentiation is simple: when retrobulbar neuritis, in particular with papillitis caused by it, a decrease in visual acuity occurs acutely or subacutely and can be very pronounced, whereas with a stagnant disc, visual acuity does not change for quite a long time (weeks, months) or its changes remain insignificant.

With retrobulbar neuritis, some pain may occur with movement. eyeballs and pressure on them. Characterized by predominant loss central vision, wherein peripheral vision maybe in that one

or otherwise remain intact. One of the main causes of retrobulbar neuritis is autoimmune inflammation, accompanied by demyelination of optic nerve fibers.

Restoration of visual acuity usually occurs several weeks after its decline, appears gradually, and eventually vision is restored, reaching usually baseline. IN in rare cases A small central scotoma persists for a long time in the field of vision of the affected eye. Later, some pallor (atrophy) of the optic disc may be detected, especially significant on its temporal side. Manifestations of retrobulbar neuritis can recur.

In persons who have had retrobulbar neuritis, subsequently, within 10-15 years, in 20-40% of cases, signs of demyelination develop in other parts of the central nervous system, which makes it possible to diagnose a common demyelinating disease - multiple sclerosis, which is the most common cause of retrobulbar neuritis.

Bilateral optic neuritis may precede the development by several days or weeks clinical picture transverse myelitis. The combination of retrobulbar neuritis on both sides and acute transverse myelitis is known as acute neuromyelitis optica, or Devic's disease.

Others besides multiple sclerosis, the causes of unilateral retrobulbar neuritis may be acute disseminated encephalomyelitis, posterior uveitis, viral infections, sarcoidosis.

Treatment. For retrobulbar neuritis, treatment with corticosteroids is indicated, which can be administered retrobulbarly. Pulse therapy with methylprednisolone is also effective (1000 mg in 200 ml of 5% glucose solution intravenously 1 time per day for 3 days, followed by a rapid dose reduction and switching to oral prednisolone 1 mg/kg/day, followed by a gradual reduction daily dose by 5 mg per day). Such treatment accelerates vision recovery, but the likelihood of subsequently developing a full-blown clinical picture of multiple sclerosis remains.

Transient monoocular blindness is attacks of rapidly developing uniform decrease (darkening, fading) of vision in one eye.

Etiology and clinical manifestations. Blindness often develops within 10-15 seconds, usually lasting from several seconds to several hours, sometimes having a recurrent nature and not accompanied painful sensations. Lshaigo818 Hydach (Greek ashaigo818 - darkening, Hydah - fleeting) is usually a consequence of transient retinal ischemia, more often occurring against the background of internal stenosis carotid artery. In such cases, monoocular blindness or a pronounced short-term decrease in vision in one eye is a symptom of ophthalmohemiplegic syndrome, in which it is accompanied by transient central hemiparesis on the opposite side. This syndrome may be a harbinger of ischemic stroke.

With transient monoocular blindness or decreased vision in one eye caused by stenosis of the internal carotid artery, a murmur may be heard during auscultation of this vessel. Confirmation of the diagnosis can be provided by ultrasound and duplex scanning, as well as carotid angiography. Treatment tactics are usually determined taking into account the data obtained from the use of these diagnostic methods.

Monocular blindness is sometimes a consequence of microembolism of the retinal arteries (arterio-arterial or cardioarterial microembolism), as well as stenosis central artery retina, anterior ischemic optic neuropathy due to giant cell arteritis, or atherosclerotic lesions ophthalmic artery or its branches.

Anterior ischemic optic neuropathy is characterized by acute painless loss of vision in one eye; V severe cases the resulting blindness may be permanent; in the fundus there may be swelling and blanching of the optic disc, peripapillary hemorrhage, the retina remains unchanged.

Central retinal artery occlusion may occur sudden blindness on one eye. Its retina in the ischemic zone is pale, at the location macular spot it can be so thin that sometimes you can see through it choroid- the result is a red spot, known as the cherry pit symptom.

Transient monoocular blindness can also be an aura of the retinal form of migraine, which is characterized by dysgemic manifestations in the retinal artery system. In such cases, a decrease in visual acuity in one eye is soon accompanied by a characteristic headache, usually on the same side of the hemicrania type, especially intense in the fronto-orbital region. Sometimes patients with the more common ophthalmic form of migraine also complain of decreased vision in one eye during a migraine attack, but in such cases, clarifying the anamnesis allows us to establish that in fact the aura manifested itself in the form of homonymous hemianopsia, usually explained by vasospasm in the posterior basin. cerebral artery. By the way, with ophthalmic migraine, photopsia and scintillating scotomas are often observed in the homonymous halves of both eyes, and attacks of hemicrania usually occur on the opposite side. Manifestations of visual aura (photopsia, scotomas, narrowing of visual fields, temporary decrease in visual acuity, sometimes even blindness), spreading over the entire visual field, can occur on both sides. This is typical for attacks of ophthalmic migraine, during which vascular reactions in the basilar artery or in both posterior cerebral arteries.

Toxic-metabolic optic neuropathy usually manifests as simultaneous visual impairment on both sides. In this case, central or centrocecal (central, merging with the blind spot) scotomas are formed within a few days or weeks.

Etiology and clinical manifestations. The cause of toxic-metabolic neuropathy in such cases may be intoxication with chloramphenicol, streptomycin, sulfonamides, isoniazid (tubazid), digitalis, digoxin, arsenic, lead, thallium, teturamo\ (antabuse). In cases of poisoning methyl alcohol(methanol) visual disturbances manifest themselves against the background of a state of intoxication in the form of acutely occurring large symmetrical central scotomas or complete numbness, as well as other signs of neurological and somatic pathology, acidosis (see Chapter 46).

Metabolic optic neuropathy may result from a deficiency folic acid, vitamins B] and B]2, usually associated with inadequate nutrition, malabsorption, starvation, and alcoholism.

Degenerative changes in the retina of the eyes and optic nerves are a possible consequence of a number of hereditary diseases, in particular Leber's disease (Leber optic neuropathy), inherited in a recessive, X-linked manner and therefore occurring almost exclusively in men. In Leber's disease, amaurosis may be congenital, or vision loss may debut later, before the age of 30. In such cases, the fields of vision narrow in parallel and the decrease in its acuity increases, up to blindness. The ophthalmoscopic picture can vary widely. In particular, signs of primary atrophy of the optic discs, narrowing of the arterioles of the retina, fundus pigmentation, the appearance of granularity in the macula area, diffuse white lesions, and signs of chorioretinal atrophy in the fundus can be detected. Electroretinograms show pronounced changes characteristic of taperetinal degeneration.

Severe visual impairment up to blindness due to damage to the retina and optic nerve is one of the most important signs a group of lysosomal diseases related to gangliosidoses and inherited in an autosomal recessive manner, which until recently were known as amaurotic idiocies (Tay-Sachs disease, etc.).

Finally, senile macular degeneration and various shapes retinitis pigmentosa, retinal degeneration and detachment, cataracts and other diseases and traumatic lesions of the refractive media of the eye.

From decreased vision and blindness (amaurosis) with early childhood amblyopia is significantly different - decreased vision caused by the functional characteristics of certain structures related to the visual analyzer. Variants of amblyopia: a) anisometropic amblyopia - character

is characterized by a poorly corrected decrease in visual acuity of the eye with more pronounced ametropia (refractive error); b) refractive amblyopia, caused by a refractive error (mainly with high degree hypermetropia and astigmatism), not amenable to optical correction; c) amblyopia due to anopsia is the result of functional inactivity of the eye, for example, with severe monolateral strabismus and constant inhibition in connection with this of the function of the central vision of the squinting eye.

Visual acuity is the main parameter visual system. Normal acuity is considered to be vision equal to one. As a result various diseases or age-related changes, a decrease in visual acuity may occur.

Causes of decreased visual acuity

There are many reasons for deterioration in visual acuity. All of them are divided into two types:

• optical. Associated with defects in the optics of the eye. They cause diseases such as farsightedness, astigmatism, and myopia. Decreased visual acuity in in this case manifests itself in cloudiness and blurriness of the image of objects at any distance;
• sensory. Impaired light perception and visual processing. Deterioration in light perception usually occurs due to disease of the retina, optic nerve, or brain. Symptoms of decreased visual acuity with impaired light perception are also known.

Diagnostics of visual acuity

Diagnosis of decreased visual acuity is carried out by an ophthalmologist. The most common diagnostic method is to use a 12-row table of letters, rings or pictures. The table is compiled in such a way that a person with normal visual acuity can easily distinguish the tenth line of letters or images from a distance of 5 meters. Each top row of the table corresponds to a visual acuity of 0.1. If a person does not see the signs of the first row, then his visual acuity is less than 1.0. In complete blindness, vision is 0.
Another method of examination for decreased visual acuity is testing using special light projectors that transmit images of letters and signs to a screen in a darkened room.

To determine retinal visual acuity when the optical media of the eye are clouded, a laser retinometer is used. Each eye must be examined separately, since visual acuity may differ for each eye. The examination usually begins with the right eye.

Treatment of decreased visual acuity

When the first signs of a decrease in visual acuity appear, you should consult a doctor, since very often such deterioration progresses and leads to partial or complete loss vision. Treatment is primarily aimed at correcting the underlying disease. Typically, the patient is prescribed glasses with individually selected lenses. This will help improve the quality of vision and relieve unnecessary eye strain. It is very important not to overstrain your eyes and observe the light regime. Besides drug therapy underlying disease, a complex of vitamins for the eyes is prescribed: A, B, C, E, lutein. It is possible to prescribe hardware procedures, magnetic therapy, electrophoresis. Eye gymnastics is a must. A set of measures to improve visual acuity is selected individually and depends on many indicators of the condition of the human body as a whole.

Decreased visual acuity without visible reasons may be caused by eye strain. In this case, rest and reduction of visual load are indicated. Typically, this deterioration in eye health is reversible and does not require serious medical or surgical treatment.

Decreased visual acuity is a very common pathology that can be caused by the most different reasons. One of these reasons is violations, and this anomaly takes a leading place in the list of factors leading to a decrease in

Causes of visual impairment

However, refraction is not the only reason for visual impairment; very often it becomes a consequence of diseases or changes that occur in the tissues of the eye, such as:

A common disease in which intraocular fluid due to improper outflow, it provokes excess pressure inside the eye, which leads to dysfunction of the optic nerve.

A disease characteristic mainly of older people. It occurs due to thickening and clouding of the lens. The main signs of this disease are spots before the eyes, blurred images, a halo around the light source, blurred vision at dusk.

Age-related macular degeneration ()- another pathology of older people. It manifests itself due to wear and tear of the macula (macula), the part of the retina that is responsible for visual acuity in central region. According to statistics, macular degeneration is the main cause of blindness in the elderly population in all developed countries.

Diabetic retinopathy. This disease is one of the most serious complications diabetes mellitus and is characterized by progressive damage blood vessels retina, which ultimately leads to vision loss and sometimes complete blindness. The statistics on this disease are very disappointing. Diabetic retinopathy threatens every twentieth Russian today.

Prevention of vision loss

It is important to know that it is possible to stop the progression of the disease and maintain or restore vision in more than 80% of all cases. You just need to identify the disease in time and then carry out adequate treatment.

It's worth remembering that the real reason Decreased vision can only be diagnosed by an ophthalmologist.

Self-medication in most cases leads to disastrous consequences! Therefore, at the first suspicion of vision deterioration, it is better to immediately consult a doctor.

Visual acuity is usually called the minimum angular distance between image details that the eye can distinguish.

Visual acuity is the main parameter of the visual system. If a person complains of blurred vision, most likely we're talking about about decreased visual acuity.

Normal visual acuity is considered to be an angle equal to Г(1.0). Visual acuity is indicated decimal(0.2; 0.3; 0.7). It is calculated as the reciprocal of the maximum angular discrimination. For example, if the minimum visual angle is 2, then the visual acuity of that eye is 0.5 (1/2). There are people who have visual acuity of 2.0 or more, their brain is overloaded with information: they see every grain of sand on the road, every vein on the leaves. They perceive vision deterioration to 1 as a significant loss.

The minimum sufficient distance visual acuity is considered to be 0.8. To read newspaper font from a distance of 30 cm, the minimum visual acuity value is 0.5. Difficulty walking appears when visual acuity is less than 0.1.

There are many reasons for deterioration in visual acuity. They can be divided into optical and sensory. The former are associated with disturbances in the optics of the eye, the latter - with disturbances in the mechanisms of light perception and visual image processing. The main defects in the optics of the eye are: myopia, farsightedness, astigmatism, as well as clouding of the optical media of the eye. The mechanisms of light perception can be disrupted due to diseases of the retina, optic nerve and brain.

How to determine what is causing the decrease in visual acuity? Approximately this can be done, for example, using the test given in the article Causes of visual impairment.