Mar 06, 2018
Cataract - is a very insidious disease and represents a loss of transparency in the lens of the eye. Cataract - the Greek word for "waterfall" in translation. Apparently, this is due to the idea of a cloudy film that covers the pupil with a cataract and something that resembles a waterfall. In fact, cataracts are a clouding of the lens. First, a small cloudy spot appears in the field of view. Gradually( usually for several years), as the lens becomes more and more opaque, vision deteriorates, especially at night or in bright light. About 75 percent of Americans over the age of 60 have cataract signs. At a late stage, the disease is easily eliminated as a result of surgery( although many patients may delay the operation for years).
Cataract develops usually in both eyes, but most often it does not happen simultaneously. The main symptom of the disease is a visual impairment, not very significant at the earliest stages. In some patients, this stage can last for years, while in others, the cataract maturation process is very fast. The lens becomes more cloudy, losing transparency. It can also swell and increase in volume, which is accompanied by increased intraocular pressure( glaucoma) and often requires urgent surgical intervention. With mature cataracts, a person is only able to distinguish light from darkness, he practically does not see objects. Naturally, glasses with cataract can not help: they do not increase the degree of transparency of the lens.
The clinical course distinguishes three stages of cataract:
• The main risk of cataracts is associated with aging, since the main cause of its development is exposure to ultraviolet sunlight, which accumulates throughout life.
• Irradiation, including X-rays and microwave radiation, can contribute to the development of cataracts.
• Physical damage or inflammation of the eye( eg, uveitis or iritritis) can lead to the development of cataracts.
• Prolonged use of corticosteroids, hereditary factors and birth defects can contribute to the development of cataracts.
• In people with diabetes, cataracts can develop at an earlier age.
Although modern medical science does not know exactly which processes determine the origin and development of cataracts, and why sometimes one eye is affected more than the other, we can state with complete certainty the following:
• changes in the lens are a normal age process;
• there is a relationship with certain diseases;
• Some medications can stimulate the appearance of clouding of the lens( for example, long-term use in large doses of hormonal drugs - prednisolone and others);
• the occurrence of cataracts may be due to eye trauma;
• Cataract often occurs after inflammation inside the eye;
• Some types of radiation contribute to the development of cataracts;
• Cataract may be congenital.
• Gradual painless vision impairment or double vision.
• Iridescent circles or a foggy spot around the light source. Vision can improve in dim light, while bright lighting leads to a narrowing of the pupils and increases the passage of light through that part of the lens that is most affected by cataracts.
• Increased sensitivity to light and shine.
• Poor color perception.
• Temporary improvement of near vision( for a short period the patient may not need reading glasses).
• Frequent change of glasses or contact lenses.
• Difficulty with driving at night or in bright light.
• With a strong development of cataracts, the pupil becomes turbid or turns yellow.
• Eye examination by an ophthalmologist.
• To reduce the impact of bright light outside, wear a hat with large margins or sunglasses.
• Indoors, use desktop or floor lighting with an incandescent lamp;Do not use chandeliers or fluorescent lamps. Avoid narrowly focused halogen lamps that cause the pupils to narrow. Use the light control.
• For reading, choose newspapers and books with a large font.
The most reasonable time for determining the time of an operative intervention is the indicator not of time, but of a decrease in visual function. The operation should be done after the vision of the cataracted eye has dropped by 20-30%.It is at these terms that the removal of the lens gives the best result.
Types of surgical intervention
Currently, operational techniques are well developed, most clinics have the latest equipment and microsurgical technologies. As a result, almost all surgical interventions for the removal( extraction) of cataracts proceed without any subsequent complications.
In the middle of the last century, the so-called cryoextraction of cataracts was widely used, when the clouded lens was removed very strongly by a cooled tool( down to minus 50-60 ° C).Since then, technology has changed and the technique itself, but still the operation is to remove the entire contents of the lens bag, but with the retention of its back wall. This makes it easy to implant an artificial lens.
Extracapsular extraction of cataract. Through a cut on the cornea, the lens is removed without its capsule, the artificial lens is implanted, and then the sutures are placed on the cornea. The operation lasts about half an hour. The patient is discharged home in a week, but the seams from the cornea are removed only after 3-4 months. Vision, as a rule, is restored in 2-4 weeks.
Intracapsular extraction. The lens is removed along with its capsule. This type of surgery is extremely rare and only in connection with serious indications, since in this case the risk of postoperative edema with subsequent retinal detachment is high.
Since the late 60s of the last century, ultrasound has been increasingly used to remove cataracts. The method with the use of low-frequency ultrasound is called phacoemulsification, and lately it has been most widely used. The removal of cataracts through small and super small incisions makes this operation less traumatic, while simultaneously reducing the risk of possible complications. True, this technique allows you to remove cataracts not in all patients: this is due to the negative influence of ultrasound on the tissue. In these cases, the laser is used for the operation. The type of operation is individual for each patient and is determined exclusively by the doctor after a number of necessary studies. The duration of phacoemulsification is of the order of 20 minutes. The surgeon works with a special microscope, which not only increases, but also brightly illuminates the entire operating field. The procedure for the surgery itself for the surgical removal of the cataracts affected by the cataract is well worked out: to date, at least 95% of the operations have been successful and lead to a significant improvement for many years. I must say that imported electronic equipment is often used. Phacoemulsification is well tolerated even by elderly people over the age of 80 years.
Briefly about the operation itself: is first cut( 3-4 mm) and through it a hollow needle with a silicone coating is inserted into the lens to protect the tissue from damage. It sends ultrasound of a strictly defined frequency, which breaks the clouded core of the lens. The mass is then sucked off with a special device that cleans the inner surface of the capsule. After this, an intraocular lens, that is, an artificial lens, is inserted by a special injector.
Why is phacoemulsification not always performed? If the cataract is very large and dense, there is a pronounced weakness of the ligamentous apparatus, a subluxation or dislocation of the natural lens, corneal disease, and also some other features of the structure of the eye, it is not only technically extremely difficult to do such an operation, but also impractical because of possible complications. The final decision on how to remove cataracts is taken strictly according to the state of the eye.
As a rule, surgical treatment is accompanied by hospitalization, and the time spent in the clinic is from 1 to 4 days. Hospitalization is often a compulsory procedure, since in most cases patients are elderly people and they need to observe a doctor-therapist, cardiologist, neurologist and performing pre-operative examinations( for example, performing an electrocardiogram or passing special blood tests), as well as monitoring specially trained personnelin the first hours / day after the operation. In some institutions and in some cases, cataract operations are performed on an outpatient basis, that is, on the day of treatment.
Before the operation, it is necessary to make general blood and urine tests, as well as blood tests for syphilis, human immunodeficiency virus( HIV), hepatitis B and C markers, perform chest fluorography and an electrocardiogram, and see a dentist and otorhinolaryngologist, therapist. In addition, you need to get an operation permit from the doctor with whom the patient has to deal with an existing chronic disease( for example, an endocrinologist in the presence of diabetes or a cardiologist with coronary heart disease).The purpose of such an extended examination is to identify acute inflammatory processes or exacerbation of chronic diseases.
Before the operation to prevent the onset of inflammatory processes, eye drops are prescribed. Usually these are special antibacterial and anti-inflammatory drugs that are digested for a day or the day before the surgical treatment. In the postoperative period, antibacterial, anti-inflammatory drops and accelerating healing eye gels are necessarily prescribed. The multiplicity and duration of application is determined by the ophthalmologist individually. As a rule, drops are prescribed at least 4-5 times a day for 4-6 weeks according to a special scheme.
Basically, local anesthesia is used during surgery. In addition, appoint mild sedatives( in tablets or intramuscular injections).Currently, general anesthesia is used extremely rarely, since the risk of using it can be significantly higher than the operation itself.
The decision on the type of anesthesia is taken individually depending on the age of the patient, the presence of concomitant pathology, the preference of the surgeon. In any case, it should be remembered that the operation is performed on a special operating table in the patient's position "lying on his back".It is especially important for the patient to be able to look at his feet without lifting his head. It is useful to learn this in advance.
There are no painful sensations during the operation. A patient may be bothered only by the effect of surprise( bright light, a sense of "foreign body" and other).During phacoemulsification a special self-sealing cut is used, which does not require suturing.
In most cases, two hours after surgery, the patient is allowed to get up. The next day, the visual acuity is checked, and on the third day the patient, as a rule, leaves the hospital.
In general, the operation is safe, but sometimes complications may occur in the postoperative period: retinal edema, inflammation of the inner shells of the eye, a brief increase in the level of intraocular pressure, and finally a very rare( less than 0.1%), but the most formidable condition,cataract, is a detachment of the retina.
If the patient is present and cataracts, and glaucoma, the actual question is: what to operate first. The answer can not be unambiguous. The decision is made individually by the attending physician, taking into account the stage of glaucoma, stabilization of the glaucoma process, compensation of the level of intraocular pressure. In most cases, first an anti-glaucoma operation is performed, then, in the second stage, an operation for cataracts. A period of 1 to 1.5 months is considered sufficient to restore the eye after the first operation. In a number of cases, combined intervention is performed: simultaneous anti-glaucoma surgery and removal of cataracts with implantation of the artificial lens, which is also determined individually.
• The use of drugs in the initial periods of cataracts of different origin leads to an improvement in metabolic processes in the lens. The main directions of such treatment are the replacement of the lack of those substances, the deficit of which is observed in cataracts, the normalization of metabolism and the oxidation-reduction balance. How to treat this ailment with folk remedies, look here.
However, it is extremely difficult to achieve the restoration of metabolic processes in the lens, as evidenced by the large number of different drugs currently offered by pharmaceutical companies and laboratories in several countries for the medical treatment of cataracts( more than 60 different brand names).
Drugs used to influence the metabolism in the lens can be divided into several groups:
• products containing inorganic salts necessary to normalize electrolyte exchange and reduce the dehydration of the lens;
• drugs aimed at correcting metabolic processes in the lens;
• drugs that have organic compounds that normalize the redox processes in the lens.
Unfortunately, absolutely reliable and effective medicines that can cure cataract have not been developed anywhere in the world.
Among the ready-made dosage forms the most widely used quinaks, katakrom, senkatalin, vitayodurol, drops Smirnova, vice and others. Their systematic use improves the nutrition of the lens, and it is quite possible for some time to delay the development of cataracts. Nevertheless, it is impossible to completely stop the process of turbidity with the help of drops alone: they can slow it down and only at the best, suspend, but only for a while.
• The only way to cure cataract is the operation of ( successful results are achieved in 95 percent of cases).It can be delayed indefinitely, but it is advised to do it when the cataract begins to interfere with daily activities. During the operation, the lens is removed and replaced with a plastic implant.(While the implant is getting used, special contact lenses or glasses can be used.)
• Contact an ophthalmologist if you have visual problems.
• Wear sunglasses labeled "general purpose" or "special purpose" or glasses that say that they hold at least 95 percent of the ultraviolet rays.