How to correct short-sightedness? Part 1
On the website appeared interesting article with the description of process of operation on correction of short-sightedness. Now there are many ways of correction and “ disposals “ from short-sightedness (miopiya), only options of surgical intervention more than five. To help “ to four-eyes “ (which also I treat) to choose the acceptable option, I will shortly describe the main. In due time I attentively studied them, but stopped on points which remain the simplest, cheap and safe method of correction of short-sightedness today.
Contact lenses have a number of advantages before points and can provide normal life even to very active and sports young man. But their carrying is connected with certain inconveniences. Long process of accustoming - yet not the most unpleasant. Frequent complication are allergies, and many “ kontaktnik “ it is easy to recognize by constantly red eyes. There is also a risk of infectious complications, including heavy, threatening with total loss of sight. It is contraindicated to carry lenses during any, even the most slight, catarrhal diseases. Process of removal and installation of lenses is quite unpleasant, besides, the contact lens can come off at the most inappropriate moment.
it is desirable for i to treat of surgical correction carefully, she is possible in cases of intolerance of contact lenses, insufficient-point correction, professional need and some other the individual reasons. Types of the surgeries applied to treatment of short-sightedness exists a little.
Keratotomiya - the checked and very reliable method at weak and average degree of a miopiya. At it the special surgical tool notches on the periphery of a cornea become, without mentioning the central optical zone. Due to scarring of notches there is a cornea curvature (new optical curvature) and, respectively, change of focal length that leads to formation of the image of objects directly on a retina.
FRK (a fotorefraktivny laser keratektomiya) - is carried out at weak and average degree of a miopiya. It is carried out in the central zone of a cornea where the dosed removal of fabric of a cornea by an evaporation method by means of the excimer laser is made.
FRK represents contactless influence an eksimer - the laser on cornea blankets, without influence on other structures of an eye. At the same time the laser, working in the scanning mode, “ irons “ and “ models “ its surface. Operations of the laser cope the computer program. Practically it is even impossible to call it operation in habitual understanding since oftalmokhirurg directly does not interact with eye tissues. As a result of FRK, on a blanket of a cornea remains “ microerosion “ which begins to live within 24 - 72 hours with formation of new optical curvature.
Laser keratomilyoz or " technology; lazik “ (lasik, leysik) - a combination of surgical and laser equipment. It is carried out at high degree of short-sightedness. Represents a modern type of correction of sight - a combination microsurgical and an eksimer - laser technologies. It is one of most “ sparing “ methods, keeping anatomy of layers of a cornea. After operation in the same evening it is possible to watch TV and to read.
Lazik consists of two combined operation stages. The first stage includes use of the automatic microsurgical tool which opens access to the center of corneal fabric. This procedure takes several seconds and is absolutely painless. Partially the top layer of a cornea in the form of a round rag of 8 mm and more separates. On the one hand the rag remains attached to a cornea and after the second stage of operation comes back to the place.
The second stage of laser correction consists in use of the high-precision excimer laser operated by the computer for creation of a new profile of a cornea that further beams were focused on an eye retina. After “ processings “ cornea surfaces, the rag separated at the first stage comes back to the place. As a result the superficial protective layer of a cornea is practically not damaged (as at the FRK method), and in most cases the patient does not feel any discomfort after operation.
Keratomilez - a modern surgical technique by means of the special device a microkeratoma. It is effective at very high degree of a miopiya (more than 15,0 dioptries). The name of operation consists of two Greek words - “ kerato “ (cornea) and “ milez “ (sculpture). Its essence consists in modeling of curvature of a forward surface of a cornea that leads to change of its optical power. In case of a keratomilez donor material is not used, and the dome of own corneal tissue of the patient which is previously removed mikrokeratomy is ground in the frozen look. After giving of the corresponding thickness and a form to it it is sewn on the former place.
Replacement of a transparent crystalline lens on artificial or donor - operation with a possibility of more serious complications. However when replacing a crystalline lens there is no impact on a cornea and change of the refracting force of an eye occurs on more natural way - due to change of the refracting crystalline lens force. This operation allows to avoid such serious risk as decrease in contrast sensitivity. However at the same time ability to accommodation is lost (“ " control; for obtaining the accurate image of distant and close objects). Therefore replacement of a transparent crystalline lens is recommended to patients 40 years are more senior.
There are also other types of surgical correction of short-sightedness, but they are used much less often.
About not surgical ways of correction of short-sightedness in 2 parts of article.