Age-related macular degeneration: causes and treatment

To keep good vision until old age is very difficult. Often in the old age, the ability to see is gradually lost. This is due to the fact that all human organs with time begin to "wear out". One of the first is the tissue of the eye. It is believed that vision is deteriorating already from 40-45 years. This happens even in cases where a person previously had no problems with vision during life. Deterioration of vision occurs gradually. Most people are concerned about "farsightedness", that is, the inability to see objects that are close. Sometimes, more serious problems develop. These include pathologies such as cataracts, glaucoma, etc. Another common disease is age-related macular degeneration. Such ailment is dangerous because it can lead to loss of vision.

The concept of age-related retinal degeneration

Age-related macular degeneration (AMD) is a pathology that develops due to dystrophic processes in the retina of the eye. This area is directly connected to the brain (it is a peripheral analyzer). With the help of the retina, the perception of information and the transformation of it into visual images are formed. On the surface of the peripheral analyzer there is a zone that contains a lot of receptors - rods and cones. It is called the macula (yellow spot). Receptors, of which the center of the retina consists, provide color vision in humans. In addition, it is in the macula that light is focused. Thanks to this function, the sight of a person is distinct and clear. Age-related macular degeneration of the retina leads to dystrophy of the tissue of the macula. Changes are not only to the pigment layer, but also to the vessels feeding this area. Despite the fact that the disease is called "age-related macular degeneration," it can develop not only in the elderly. Often the first symptoms of pathological changes in the eye begin to be felt by age 55. To the elderly and senile age the disease progresses to such an extent that a person can completely lose the ability to see.

Age-related macular degeneration of the retina refers to common ailments. Often this pathology causes disability and disability. It is widely distributed in America, Asia and Europe. Unfortunately, the disease is often diagnosed at later stages. In these cases it is necessary to resort to surgical treatment. However, with timely therapeutic treatment, as well as the implementation of preventive measures, it is possible to avoid surgical intervention and complications of pathology (blindness).

Causes of development of age-related macular degeneration

Like all degenerative processes, this disease tends to a slow and progressive course. The causes of dystrophic changes in the yellow spot of the reticular membrane can be different. The main one is the involution of the eye tissues. Nevertheless, in some people dystrophic changes occur more quickly, while in others - more slowly. Therefore, there is an opinion that age-related macular degeneration is inherited (genetically), and also predominates in persons of European nationality. Other risk factors include: smoking, hypertension, frequent exposure to the sun. Based on this, it is possible to identify the causes of macular degeneration. These include:

1. Vascular lesions. One of the risk factors is atherosclerosis of small arteries. Disruption of oxygen delivery to the tissues of the eye is one of the main mechanisms for the development of degeneration.
2. Excess body weight.
3. Lack of vitamins and some trace elements. Among the substances needed to maintain retinal tissues, we can distinguish: lutein and zeaxanthin.
4. The presence of a large number of "free radicals". They increase the risk of degeneration of organs several times.
5. Ethnic features. The disease is more common in people with a light eye color. The fact is that in the representatives of the Caucasoid race the density of the pigment contained in the retina is low. For this reason, dystrophic processes develop faster, as are the symptoms of the disease.
6. Incorrect food.
7. Being in direct sunlight without goggles.

Pathology often develops in people with a hereditary anamnesis (the presence of the disease in parents, grandmothers). In most cases, the ailment is diagnosed in the female population.

Age-related macular degeneration: pathophysiology of the process

Like all degenerative changes, this disease has a complex development mechanism. In addition, the pathogenesis of dystrophic processes is still not fully understood. It is known that under the influence of unfavorable factors, the tissue of the macula is irreversibly damaged. Most often, pathology begins to develop in people suffering from vascular diseases (atherosclerosis, diabetes), obesity. Also, the ailment is almost always found among the smoking population. Due to blockage of the vascular bed and insufficient supply of eye tissues, age-related macular degeneration develops. The pathogenesis of the disease is based on the disturbance of the oxidation-reduction balance. The main role in this process is played by free radicals. These substances are formed in the macula for several reasons. First, the yellow macrocosm of the retina is constantly affected by oxygen and light. In addition, in this area there is a conglomeration of fatty acids, which tend to oxidize. Another factor in the pathogenesis of the development of pathology is the origin of the retina. After all, this shell of the eye is considered a peripheral analyzer and is directly connected with the brain. Therefore, she is particularly sensitive to "oxygen starvation."

All these factors predispose to the fact that the tissue of the macula is gradually thinner. As a result of the action of radicals, the cell membranes are destroyed. The retina becomes even more sensitive to light. Under the influence of ultraviolet and infrared radiation, AMD develops even faster. All these processes lead to the fact that the epithelium of the macula begins to "lose" the pigment receptors, undergoes atrophy. If the time does not stop the destruction of the macula, a detachment of tissue occurs. The final stage is the appearance of scars and the development of blindness.

Forms of age-related retinal degeneration

There are 3 forms of macular degeneration. This classification is based on the morphological changes occurring in retinal tissue. This division is necessary to determine the tactics of treatment of the disease.

Morphological types of the disease:

1. Age-related macular degeneration is a moist form: characterized by the presence of exudate. This option is rare, in 20% of cases. It is distinguished by a rapidly progressing current. If a person's eyesight deteriorates rapidly (within a few days), then one should suspect such a disease as age-related macular degeneration. The moist form develops due to neovascularization, that is, the appearance of a large number of new vessels on the retina. Given the damage in the membranes of cells, their permeability increases. As a consequence, edema and hemorrhage develops.
2. Age-related macular degeneration is a dry form: characterized by a slow flow. In another way this type of pathology is called atrophy. Dry age-related macular degeneration develops in 90% of patients. On examination, druses are noted - bright foci of atrophy, insufficiency of the pigment layer, defects on the epithelium.
3. Cicatricial form of macular degeneration. It is considered the final stage of AMD. It is characterized by detachment of the epithelium and the formation of connective tissue (scar). In this case, complete loss of vision is noted.

In some cases, the dry form of AMD moves into an exudative variant of the disease. Most often this occurs with vascular lesions, in particular - diabetic retinopathy. Such changes indicate a worsening of the forecast and are a signal for urgent measures.

Symptoms of age-related macular degeneration

Depending on the form of AMD, the symptoms of the disease can develop both slowly and quickly. Often a long time macular degeneration does not make itself felt for several years. With the dry form of AMD on the surface of the retina, there are druses - sites of atrophy. As a consequence, vision gradually deteriorates. The pigment layer suffers more, because of what the brightness of the flowers is somewhat lost. The visual acuity can change at the same time, but insignificantly. The moist form of macular degeneration develops rapidly. For a few days, vision can deteriorate significantly, down to complete blindness. Due to edema and increased permeability of membranes, hemorrhages that can be seen with the unaided eye can occur. Symptoms observed in AMD:

1. Change the contrast and brightness of the image.
2. Decreased visual acuity.
3. Curvature, distortion of objects.
4. Blurred image.
5. Appearance of loss of visual fields.
6. Inability to read despite wearing glasses.

With the gradual development of pathology, signs of the disease may be absent for a long time. Then the central vision gradually deteriorates. When you look ahead, most of the image becomes fogged. Nevertheless, peripheral (lateral) vision is preserved. Gradually the affected area increases.

With wet and cicatricial form of AMD, blindness occurs quickly. Unlike the dry type of degeneration, peripheral vision is rarely maintained. With the timely treatment of AMD, the development of blindness can be stopped.

Diagnosis of age-related retinal degeneration

Age-related macular degeneration can be diagnosed in the early stages. Therefore, people suffering from vascular lesions should be examined at an ophthalmologist 1-2 times a year. The diagnosis of AMD is based on the history and special examination. Elderly people often complain about the appearance of a "stain" in front of the eyes, reminiscent of fog. The diagnosis of "macular degeneration" is most often associated with impaired vision in women, especially if there is a history of type 2 diabetes, atherosclerosis of the vessels. In addition to the survey, a number of ophthalmological examinations are performed. Among them - measurement of visual acuity, perimetry, stereoscopic biomicroscopy.

To assess the state of the vessels, fluorescent angiography of the fundus is performed. Due to this research, it is possible to detect zones of epithelial detachment, atrophic druses, neovascularization. However, this method of instrumental diagnosis has contraindications and risks. Therefore, before deciding on a test, it is worth to visit an ophthalmologist and get his advice.

How to treat a dry form of macular degeneration?

When confirming the diagnosis, it is necessary to immediately begin treatment of age-related macular degeneration. The dry form of the disease is less aggressive, so it succumbs to medical therapy. This does not help to get rid of the pathology in full, but it will suspend (slow down) the process for several months or years. First of all, with AMD it is necessary to follow a diet. Given that atrophic processes develop due to a lack of carotenoids and clogging of the vessels of the fundus, the patient should exclude animal fats. To prevent atherosclerotic changes in the small arteries of the retina, a large number of fruits, greens, and vegetables should be eaten. In addition, such a diet will help fill the lack of vitamins and trace elements.

To cope with free radicals, it is recommended to spend less time in the sun. Also, patients should consume antioxidants. They include vitamin E and C. To improve blood flow to the fundus, it is recommended to use antiaggregants, vasodilating drugs.

Age-related macular degeneration - wet form: treatment of pathology

With wet form of macular degeneration, not only drug therapy is performed, but also surgical treatment. The drugs that restore the retinal pigment layer include medicines "Lutein" and "Zeaxanthin." These medicines belong to the group of antioxidants. In addition, it is recommended to eat foods containing zinc. If the disease has developed due to diabetic retinopathy, it is necessary to carry out a hypoglycemic therapy under the control of the glycemic profile.

Surgical treatment of retinal degeneration

One drug therapy is not enough if the patient is diagnosed with "age-related macular degeneration". Treatment of pathology should be combined with surgical correction. Especially it concerns the wet form of AMD. Currently, almost every ophthalmologic clinic performs laser treatment of macular degeneration. It can be different. The choice of method depends on the stage of AMD and manifestations of pathology. The following methods of surgical correction are distinguished:

1. Laser coagulation of the neovascular membrane.
2. Photodynamic therapy with the drug "Visudin".
3. Transpupillary laser thermocorrection.

With the possibility and absence of contraindications, transplantation of pigment epithelium, vitrectomy (with hemorrhage into the vitreous of the eye) is performed.

Prophylaxis of age-related retinal degeneration

To preventive measures include: adherence to diet, weight loss. When vascular lesions are recommended to quit smoking. Also, avoid direct exposure to sunlight to people who have a light eye color. In addition, prevention includes the use of vitamins to strengthen vision and trace elements.