Cataract is a pathological process, as a result of which the optical properties of the lens of the eye change. As the cataract develops, the lens loses elasticity, becomes cloudy, gradually losing the ability to pass and focus light rays on the retina of the eye. Most often, this process is associated with an age factor: most patients with cataracts are elderly.
The lens of the eye is a natural lens that transmits and refracts light, as a result of which an inverted image is formed, which is then correctly interpreted in the visual center of the brain. The lens is located between the vitreous body and the iris of the eye. Normally, it is elastic, has a transparent homogeneous structure and instantly “adjusts” when looking from the near position into the distance and vice versa. This ability of the eye to autofocus (accommodation) allows you to distinguish large and small objects equally well at any distance. With age, the lens thickens and becomes cloudy, its reaction and elasticity limit decrease. This is the beginning of the development of cataracts. Due to the decrease in the capacity of the lens, less light rays fall on the retina of the eye, the contours of objects are blurred, when the gaze is transferred from near objects to distant, vision focuses with a delay. The further development of cataracts depends on many factors. A decrease in vision to one degree or another always occurs over time. In the absence of dynamic observation and timely treatment, cataract can lead to complete blindness.
Senile cataracts are most often diagnosed. After 50 years, the risk of age-related lens opacity increases significantly. However, at a younger age, it is also possible to develop degenerative changes in the lens, for example, due to traumatic or radiation damage, as a complication of other diseases or due to genetic predisposition.
According to statistics from the World Health Organization, there are about 17 million people with cataracts in the world. Most of them are elderly patients. At the age of 70-80 years, clouding of the lens is observed in 26% of men and 46% of women. After 80 years, cataracts develop to one degree or another in almost everyone. According to WHO, 20 million cataract patients could not avoid total blindness.
Causes of cataracts
The main risk factor for developing cataracts is age. Other common causes of lens opacity include:
- congenital predisposition to degenerative changes of the lens;
- eye injuries (especially penetrating wounds of the eyeball);
- thermal and chemical burns of the eye (liquids and vapors);
- background ophthalmological diseases (glaucoma, severe myopia);
- diseases of the endocrine system (especially diabetes mellitus), as well as other chronic systemic disorders (vitamin deficiency, deficiency of micro- and macroelements in the body, other metabolic abnormalities);
- high doses of radiation (radiation therapy, UV, microwave), including neglect of the need to protect the eyes from direct sunlight;
- large doses or prolonged use of certain medications;
- the effect of radiation;
- poisoning of the body with highly toxic substances, especially neurotoxins;
- social and environmental factors that create permanent unfavorable conditions for life and health;
- nicotine and alcohol addiction.
Cataract symptoms
“Kataraktes” from ancient Greek means “waterfall”. The name of the disease is suggested by the peculiarities of visual disorders. The contours of objects become indistinct, double, and wavelike. It really looks like a healthy person looking through water or fogged glass. In its development, cataract is also manifested by imaginary spots and stripes in the field of vision, painful perception of bright light, the illusion of a glowing halo around objects. Of course, such changes reduce the quality of life, since they complicate or exclude activities related to the concentration of visual attention on small objects and details: reading and writing, sewing, knitting, repair of equipment, etc.
Stages of age-related cataract
Cataracts are classified according to the severity of objective changes in the lens and the severity of subjective symptoms; in ophthalmology, the term “maturation of cataracts” is used. There are four stages of the disease:
- Initial cataract. The lens is predominantly clouded outside the active optical zone. As a rule, visual distortions are noted in peripheral areas (“lateral vision”), there may be only a slight decrease in visual acuity.
- Immature cataract. The opacity of the lens spreads from the edges to the center of the optical zone. At this stage, vision deteriorates significantly, and patients most often seek medical help first.
- Mature cataract. The entire lens is involved in the pathological process, the opacity becomes total. Residual vision allows you to distinguish only the level of illumination of objects and their fuzzy contours. The pupil brightens.
- Overripe cataract. Progressive clouding leads to complete blindness. The fibers of the lens decompose, the substance acquires a liquid consistency. The lens is inelastic, the pupil is milky.
The rate of cataract development
According to the observations of ophthalmologists, in twelve patients out of a hundred, complete clouding of the lens occurs in the first 4-6 years from the onset of the disease. Rapidly progressing cataracts require as early surgical intervention as possible in such patients.
In fifteen patients out of a hundred, full maturation of cataracts takes 10-15 years or more.
In most cases (70%), extensive clouding of the lens requires treatment after 6-10 years from the moment of detection.
Cataract diagnosis
Success in the treatment of cataracts largely depends on the stage at which it is detected. The prognosis is more favorable with early diagnosis of changes that have begun in the lens. However, at the initial stage, the cataract practically does not manifest itself – visual acuity does not change significantly – therefore, a visit to an ophthalmologist is postponed, as a rule, until the opacity reaches the optical region of the lens and the person begins to experience noticeable discomfort.
The initial cataract can be detected by examining the fundus. An experienced ophthalmologist will detect even a slight opacity and prescribe a more detailed examination. A specific study to clarify the diagnosis is biomicroscopy of the eye. A directed beam in the form of a light slit allows you to uniquely identify a cataract and assess the stage of its development.
This method of examining the eyeball was invented in the early twentieth century by physicist Guldstrandt (Sweden) and was called a “slit lamp”. During such an examination, the lens is illuminated by the reflection of a light beam, which is projected onto the slit diaphragm. To achieve a diagnostic effect, the optical and lighting systems of the device must be focused at the point to be studied. The device allows you to manipulate light and optics in different planes during diagnostics. This creates conditions under which the contrast of illuminated and darkened eye tissues is clearly discernible. The pattern observed during the study is called “light activity” and allows us to assess the organic and functional state of the eye structures.
Cataract Treatment
Cataract requires dynamic observation and timely treatment. Matured cataract with subsequent development gives complications to the entire anterior chamber of the eye. Secondary glaucoma may develop due to impaired outflow of intraocular fluid. If you do not seek the help of an ophthalmic surgeon in time, your vision will be irretrievably lost.
Medical treatment of cataracts
Doctors tried to solve the problem of the clouding lens in ancient times. Thus, the Greeks mistakenly believed that the cause of visual disturbances is the accumulated cloudy fluid between the lens and the iris of the eye. Egyptian healers tried to restore vision with lotions with cloves, honey, wine, milk and nutmeg. With the accumulation of knowledge about this disease, treatment began to be approached more selectively and scientifically. The first drops to slow vision loss were a solution of potassium iodide. This drug has a beneficial effect on the structures of the eye in many situations, it is still used, but it does not have a significant effect on the process of clouding the lens.
Eye drops for immature cataracts KATALIN is a drug from Senju (Japan) for initial and immature cataracts.
The composition of CATALIN includes Pyrenoxine, which inhibits the action of the breakdown products of amino acids and thereby prevents the formation of lens opacities and the progression of cataracts.
The high efficacy of CATALIN was noted in patients with age-related cataracts and in comparative study using objective research methods based on measurements of lens transparency.
Surgical treatment of cataracts
Modern medicine offers more successful, safe and radical ways to restore vision. The most effective surgical technique for cataract removal combines phacoemulsification and implantation of an artificial lens (IOL, intraocular lens). At the first stage, the ophthalmic surgeon removes the clouded lens using ultrasound. An ultra-small incision at the same time allows for subsequent implantation safely, and drip anesthesia makes the procedure completely painless. This method of local anesthesia does not burden the patient’s cardiovascular system and is acceptable for patients of all age groups.