Keratitis and contact lenses

A letter of readers came to the editor of one of the Russian publications:

- I have very bad eyesight. I want to change glasses on lenses, but I'm afraid
diseases called «Keratitis». Had to hear that it
Appears in all who wears contact lenses. Can you not
tell about me?

Candidate of Medical Sciences, Researcher of the Research Institute of Eye Diseases of the Ramne Larisa Aleksandrovna Ilyakova.

- Glasses and contact lenses are not competitors. Each has its own function. True, the lenses often have even advantages over the glasses with certain eye diseases: a high degree of myopia or hyposticity, with a difference in eye refraction, when two eye acuity varies more than two diopters, with astigmatism.

There are two groups of lenses - tough and soft. We are talking about soft lenses that have received the greatest distribution today. However, many of those who have bad eyesight, are in no hurry to abandon familiar glasses. One of the reasons is the fear of eye diseases, primarily Keratitis.

Keratitis is inflammation of the horn shell of the eye. The feature of the cornea is that it is a transparent instant fabric. Its food is carried out due to peripheral vessels. What is the appearance of Keratitis? First, with the quality of the lens, its oxygen-permeability. Soft contact lenses are made of high-quality polymeric materials, which include a large percentage of water. This allows lenses «breathe», providing free oxygen access to the cornea of ​​the eye.

Secondly, with the thickness of the lenses itself, which increases directly proportional to the size of the diopter.

Third, with «landing» and the right selection of lenses. The lens should be moving, not overlapping free access of tear fluid. There should be liquid space between the lens and the cornea. If the lenses landing is too dense, then the vessels are squeezed, and the tear does not wash the cornea. Therefore, lenses should be chosen individually, given not only the tolerability of materials from which they are made, but the form and structure of the eyes itself.

Low oxygen permeability or illiterately chosen lenses create conditions for the occurrence of keratitis.

Another problem is a forced stay in a ridiculous, punched or dusty. Lenses often react even to highly flavored deodorants. They very quickly absorb all odors, gases that immediately provokes irritation of the cornea.

In addition, there are so-called protein sediments on the lenses during long-term wearing, which are one of the reasons for the appearance of a feeling of discomfort. Therefore, contact lenses need to disinfect daily, clean and stored in a special sterilizing solution. And it should also be remembered that even the most good and expensive lenses are not eternal, as if carefully behind them you care. They must be changed. Someone every two or three months, someone after six months and later.

The cause of keratitis can be a foreign body that fell between the eye and lens. Even if it is microscopic dust. In this case, it is necessary to immediately remove the lens, rinse it and the eye itself.

I believe that it is impossible to sleep in the lenses under any circumstances. Closed eyelids Press on the lens, disturbing the trophy of the eye, its food. Even if the instructions for your lenses are allowed to sleep in them - it is better to avoid. Most often, such recommendations are just an advertising trick. Before the night rest lens should be removed and put in a fresh solution.

The first signs of the inflammation of the cornea - a blurred image and a little later - the appearance of lights. With these symptoms immediately contact the doctor. It means that your lenses are either chosen wrong, or have already failed.

British ophthalmological magazine published curious data. There are significant differences in the frequency of bacterial keratitis between contact lenses depending on the material from which they are made, and from their wearing mode.

The total frequency of keratitis when wearing contact lenses in the studied population was 362 cases (per 10,000 people who enjoy contact lenses for 1 year). In the study, all cases of keratitis were classified as light and severe on the basis of certain clinical signs. In particular, to severe cases of Keratitis, those where the corneal ulcer was observed. Frequency «lungs» Keratitites amounted to 232 cases, t.E. Almost two thirds of the total number of keratitis.

How to affect the mode of carrying contact lenses to risk to get keratitis, can be seen from the following numbers. When using contact lenses in day wearing mode (with removal overnight), the keratitis frequency was defined as 99 cases (also for 10,000 per 1 year) if the lenses were not shot even for the night for several days to 1 month (extension) Keratitis frequency sharply increased to 263 cases. Moreover, the ratio of the lungs to severe keratitis in the group of day wearing is clearly more acceptable (6: 1) than in the extension group (1.3: 1).