Dec 07, 2020
Ophthalmic laser surgery has undergone numerous tests since its invention. According to statistics, 36 million operations have been performed worldwide. But people have a misunderstanding about laser eye surgery, that is, the risk of surgery is very high. In fact, the risk of laser eye surgery is mainly due to infection.
Studies have shown that femtosecond laser surgery is safe, and both astronauts and pilots can perform femtosecond laser surgery. In addition to military personnel, professional athletes also have laser eye surgery, such as golf superstar Tiger Woods and football superstar David Beckham.
Femtosecond laser surgery is performed on the corneal tissue. There are two principles, one is the principle of optical transmission and the other is the principle of optical blasting.
Principle of optical transmission
Before the operation, the doctor enters the patient's basic information and surgical data into the computer (including the depth of laser focus; the diameter of the corneal flap, the size and width of the pedicle; the energy of laser cutting, etc.). During the operation, the doctor operates the femtosecond laser machine and fixes the cornea with a cone lens to maintain the precise distance between the laser head and the laser focus point in the corneal tissue.
The femtosecond laser machine transmits laser pulses in a pattern set by the doctor to perform various targeted ablation on the cornea. Briefly, the optical transmission principle of femtosecond lasers impressed us the most with the precise directionality and precise positioning of optical transmission.
Principle of Light Blasting
The laser pulse is focused on the corneal tissue to produce light burst; each pulse of light burst generates a micro ion, and each micro ion evaporates about 1 micron of the corneal tissue, separating the corneal tissue and forming the corresponding separation surface, which is Cutting surface of femtosecond laser. The corneal flap made during the operation is the use of this cutting mode to form a horizontal separation surface and a vertical surface.
The most advanced refractive surgery currently available is: Small incision lenticule extraction (SMILE), originally called Femtosecond lenticule extraction (FLEx), is a form of laser based refractive eye surgery developed by Carl Zeiss Meditec used to correct myopia, and astigmatism.