How exactly does an excimer laser treat myopia?

The principle of laser myopia surgery is to change the curvature of the corneal stromal layer, which is equivalent to making a biological glasses with your own corneal stromal layer.

Of course, not everyone can do it, such as being too old or too young, too much power, etc., in general, the basic requirements for patients in surgery are as follows:

1.Be between the ages of 18 and 50;

2.The degree of myopia is between 100 degrees and 1400 degrees, the combined astigmatism degree is less than 600 degrees, and the degree of hyperopia is less than 600 degrees (in principle, the actual degree varies);

3.The degree of myopia has been stable in the past two years (the annual increase is less than 100 degrees);

4.If you meet the above basic conditions, you can go to the regular ophthalmology department for a strict examination, and the examination results must fully meet the surgical standards before surgery**, if there is no standard, laser surgery cannot be done**.

Excimer laser surgery is to use the excimer laser to refractive cutting the stromal layer under the corneal flap, so as to reduce the corneal curvature in the pupil area and achieve the purpose of correcting myopia.

Hello, the excimer laser corrects myopia, astigmatism, and farsightedness by changing the curvature of the cornea so that the light is focused on the retina, and regains clear naked vision.

Excimer laser is an invisible ultraviolet beam produced by the excitation of fluorine argon gas after mixing, which is a cold laser that can accurately ablate the part of the cornea that is expected to be removed without damaging the surrounding tissues and other tissues and organs. In addition, the excimer laser has a very short wavelength of 193 nm and cannot penetrate into the eye, so there is no bad condition for the internal tissues of the eye, and there is no reason for sequelae to appear after several years.

Principle: Myopia is caused by the anterior and posterior diameter of the eyeball being too long or the anterior surface of the eyeball being too convex, and the external light cannot accurately converge in the fundus. The laser is used to cut on the corneal stromal layer, so that the curvature of the corneal surface is reduced, the refractive rate is reduced, and the focus is shifted back to the retina, so as to achieve the purpose of myopia.

The principle of excimer laser myopia surgery is to use a special extremely precise miniature corneal lamellar cutting system (referred to as corneal knife) to make the corneal surface tissue into a pedicled round corneal flap, after flipping the corneal flap, under computer control, the excimer laser is used to accurately vaporize the part of the tissue to be removed from the corneal stromal layer under the flap, and then rinse under the flap and reset the corneal flap, so as to change the shape of the anterior surface of the cornea, adjust the refractive power of the cornea, and achieve the purpose of correcting myopia, farsightedness or astigmatism.

Here, experts from ENT emphasize that when the excimer laser interacts with biological tissues, it is not a thermal effect, but a photochemical reaction, which can accurately ablate part of the cornea of the human eye and the part of the space that is expected to be removed can reach the cellular level without damaging the surrounding tissues. It has a short wavelength and does not penetrate the cornea of the human eye, so it does not have any adverse effects on the tissues inside the eyeball.

Excimer laser has a 193 nanometer cold laser produced by AFR gas decomposition and fission, which has a certain penetrating power to the human cornea, but will not produce thermal damage.

Jilin Xinhuaming Eye Hospital answers.