Laser vision correction - a procedure to remove a variety of vision problems, due to which decreases or eliminates the need to wear glasses or contact lenses. This is the most common type of refractive surgery. Refractive surgery reshapes the cornea - a transparent domed cloth in front of the eye.

What is it for

Laser eye surgery may be necessary in the presence of one of the following vision problems:

• Nearsightedness (myopia). If the eyeball is slightly longer than normal, or if the cornea is curved too sharply, the light rays are focused in front of the retina and distant objects appear blurred.
• Far-sightedness (hyperopia). If the eyeball is slightly shorter than usual, or when the cornea is too flat, the light is focused behind the retina, rather than in it. Because of this, people clearly see distant objects, but that is closer - spreads.
• Astigmatism. For this disorder characterized by an uneven curvature of the cornea, resulting in impaired vision focus.
• Presbyopia - age changes, the result of which becomes a gradual loss of the eye's ability to actively change the focus on nearby objects.

Before recommending laser vision correction, the doctor likely will offer you different ways - usually wearing glasses or contact lenses Contact lenses - whether they can completely replace the glasses? .

Risks

With laser vision correction are related to the following risks:

• Lack of correction. If the laser will remove too little tissue, vision will not be as good as hoped by the patient. Lack of correction most often occurs when short-sightedness Myopia - when visual acuity falls . To remove more tissue may need another refractive surgery - usually, it is carried out within one year after the first.
• Too much correction is possible by removing too much tissue. Correct the error is much more difficult than to correct the result of insufficient correction.
• Astigmatism can be the result of uneven tissue removal. Also in this case it requires an additional operation.
• Flaring and ghosting visible objects. After surgery, the patient may be difficult to see at night. He can see halos around lights, glare, visible objects can be split in two. Sometimes this problem can be solved with the help of eye drops containing corticosteroids, but in some cases a re-surgery. Even if the standard test conditions of the patient shows good results, his vision in dim light after the operation could have been much worse.
• Dry eye. Laser vision correction is a temporary reduction in slezovydeleniya. During the first six months after surgery, the patient may feel unusual dryness of the eyes. This in turn can impair vision. Typically, patients are advised to use the eye drops, but very strong dryness can be assigned to a special procedure to resolve this issue.

Some diseases may increase the risks associated with laser vision correction, or make it less predictable result. These include autoimmune disorders such as rheumatoid arthritis Arthritis - a variety of forms and complications , Immune deficiency caused by HIV or taking immunosuppressants, constant dryness of the eyes and corneal disease called keratoconus.

Contraindications

Laser vision correction is usually not recommended for severe hyperopia Hyperopia - than it is fraught? , Very large pupils and patients are engaged in contact sports, with classes that are more likely to get hit in the face.

Preparation for surgery

To prepare for laser vision correction:

• Stop wearing contact lenses. If you wear contact lenses, at least a few weeks before the operation start wearing glasses. Contact lenses can distort the shape of the cornea, which is why the result of the operation can not meet the expectations.
• The day before surgery, stop using makeup for the eyes - it will reduce the risk of infection. Also, ask someone to take you home from the hospital or order a taxi for a certain time.

Transaction

Laser vision correction is carried out using a laser programmed to remove a certain amount of corneal tissue.

Before surgery, the doctor conducting a survey with the help of a special device by which you can determine what form it is necessary to change portions of the cornea. This allows operation with high precision.

The whole operation usually takes less than thirty minutes. During the operation, the patient is lying in a chair with adjustable backrest. Sometimes the patient is given a sedative so that he could relax. Then, a local anesthetic is applied to the eye and use a special tool to hold the eye open.

During the operation, the patient is asked to look at the light spot. It is necessary to look remained fixed while the laser changes the shape of the cornea.

Immediately after surgery, the patient may feel a burning sensation or itching; eyes may water. Sight is stabilized for about two or three months - only then can we assess the results of the operation. About eight out of ten people, which makes laser vision correction, no longer need glasses or contact lenses. However, the result of operation in each case will depend on various factors - such as vision before surgery, the presence of various diseases, and so on.

Glaucoma Treatment depends on the stage at which it was found. The most effective treatment of this disease in the early stages, in this case an adequate comprehensive treatment can completely restore the function of the organ of vision. If you do not start treatment on time, total blindness can occur.

How to treat glaucoma

The main goal of glaucoma treatment is to reduce intraocular pressure and stabilization of visual function. Treatment is usually selected for each patient individually depending on the stage of glaucoma Stages of glaucoma - the types of disease , Intraocular pressure, the degree of disturbance of visual function, the general condition of the patient, the presence or absence of concomitant diseases.

In addition to well-appointed physician adequate treatment matters and patient participation in treatment - he should understand how important it is to keep under the control of intraocular pressure and what the consequences might be if non-compliance with this condition. The importance of this point is that it is the patient must carefully carry out all the prescribing physician. In the case of pronounced symptoms of the disease (eg, acute glaucoma attack) the patient is almost always carries a doctor's prescription.

But certain types of glaucoma (e.g., open-) at the initial stages may be asymptomatic, which often leads to impaired performance of prescribing and reduction of visual functions. To avoid such complications, glaucoma patients should be aware of all the disease.

Choice of treatment to be a doctor. How to cure glaucoma? Rather, it completely cure does not work, but it is really to maintain normal vision using different treatments.

Conservative treatment of glaucoma

Conservative treatment of glaucoma patients begin with a local hypotensive therapy - reduction of intraocular pressure with the help of drugs with local action.

Glaucoma - treatment of this disease may be different, however, there are general rules of treatment. For example, local medical treatment of glaucoma is carried out under the following rules:

• reduction of IOP should be stable - it will prevent decreased vision; thus, the more the optic nerve is damaged, the lower should be the level of IOP;
• since the drug may develop an addictive need to regularly monitor the effectiveness of treatment (studied and the state of the optic disc), and if necessary - correction of assignments;
• before treatment is determined individual level of IOP, which is required to achieve and maintain through medical treatment;
• Treatment always begins with the appointment of the drug of first choice; if it is impossible to assign (not pharmacy, patient allergies, and so on) is assigned a different drug or more (usually no more than two) drugs;
• treatment should be conducted throughout the life of the patient with periodic replacement of other drugs belonging to a different group of drugs with different mechanism of action.

The medicine for glaucoma may be applied topically, and orally or by injection (systemic action).

Local drugs for the treatment of glaucoma

All local medicines that lower IOP in glaucoma, can be divided into two groups: improving the outflow of intraocular fluid and reduce its formation.

For drugs that improve the outflow of intraocular fluid include prostaglandin F-2a (0, 005% latanoprost, 0, 004% travoprost) holinomimetiki (1-2-4% pilocarpine hydrochloride and 1, 5% or 3% karbohol) and agonists (1 -2% epinephrine).

For drugs that inhibits the production of intraocular fluid are B-blockers (0, 25 and 0, 5% timolol maleate, 0, 25, 0, 5%, Betoptik), carbonic anhydrase inhibitors (Azopt 1%, 2% trusopt), central agonists a2-adrenergic receptors (clonidine aproklonidin, brimonidine).

Widely used combination drugs for the treatment of glaucoma - fotiol, ksalakom, normoglaukon, proksofelin, proksokarpin. They are composed of drugs with different mechanisms of action, that is synergistic.

Preparations general (systemic) action for the treatment of glaucoma

The cure for glaucoma can be common action. Above all, this medication with osmotic action - glycerol, mannitol, urea, isosorbide. They are taken orally or injected intravenously. The mechanism of action of these drugs is associated with increased osmotic pressure in the blood, accompanied by a flow of fluid from the tissues into the blood, a decrease in edema, reduction in intraocular pressure and removing excess fluid How to withdraw excess fluid from the body - all sorts of ways   through the kidneys (diuretic effect).

Thus, when using mannitol IOP decreases over time, the action is continued for 6-8 hours. Preparations of this group are widely used in the relief of acute attacks of glaucoma, preparing the patient for surgery, postoperative and the need to reduce corneal edema before the examination.

For removal of tissue edema apply other diuretics for example furosemide and carbonic anhydrase inhibitors (Diacarbum). Carbonic anhydrase inhibitors reduce the production vnurtriglaznoy liquid, which leads to lower intraocular pressure. Treatment of open angle glaucoma

Treatment of patients with open-angle glaucoma Open-angle glaucoma - occurs often goes unnoticed   usually start with destination instillation solutions cholinomimetic agents, often 1% pilocarpine solution 2-3 times a day. This leads to an improvement of intraocular fluids and to lower intraocular pressure. If this fails, a prescribed instillation 2% pilocarpine solution three times a day.

With the lack of efficacy of treatment in addition designate Neostigmine, phosphacol, tosmilen to 2 times a day. Their action is also aimed at improving the outflow of aqueous humor from the eye.

If the patient has normal or low blood pressure Blood pressure - dangerous if his swing? , Then add to the introduction of pilocarpine 1-2% solutions of adrenaline. Assign as 3 - 5% solutions fetanola which has a long and gentle action on the blood vessels as compared to adrenaline. You can also use the 0, 5% solution of clonidine, a 1% solution of propranolol.

If topical treatment does not result in a sufficient reduction in IOP prescribed antihypertensives common action - carbonic anhydrase inhibitors (diakarb), osmotic agents (glycerol). and antipsychotics (chlorpromazine). Diakarb administered orally for three consecutive days with a break for 1-2 days.