Myopia laser surgery, also known as corneal myopia laser correction surgery, because the refractive power of the human cornea accounts for 3/4 of the total refractive power of the whole eye (the refractive power is the ability of the eye to focus light), so as long as a small amount of corneal thickness is changed, it can be significantly change the degree of myopia in the whole eye.
The most popular is the femtosecond laser technology. Various laser surgery methods such as "full femtosecond", "half femtosecond" and "personalized femtosecond laser" carried out by the hospital. Let's introduce the characteristics of these different laser surgeries.
Full femtosecond surgery
Full femtosecond surgery, also known as Smile surgery, is to use a femtosecond laser to pass through the surface of the cornea, cut a convex lens shape in the corneal stroma, and then make a small incision of about 2 mm above the cornea. In this opening, the laser-engraved corneal lens is taken out to achieve the purpose of treating myopia.
The advantage of full femtosecond surgery is that the corneal incision is small and the postoperative comfort is improved, but the cutting accuracy is not as good as that of excimer laser, and some personalized surgical corrections (such as kappa angle compensation, Q value correction, aberration guidance, etc.) cannot be performed, In addition, the operation is relatively more expensive for the cornea, and the allowable range of power correction is smaller than half a femtosecond.
Femtosecond LASIK
Commonly known as "half-femtosecond" surgery. It is to use a femtosecond laser to make a corneal flap. After the corneal flap is opened, a part of the thickness of the corneal stroma is ablated with an excimer laser to correct myopia and astigmatism. Because the first step of the whole process of corneal flap is completed by femtosecond laser, and the second step is completed by excimer laser, it is also called "half-femtosecond" laser surgery. This surgical method actually uses two types of lasers and eliminates the mechanical blade, making myopia surgery into a knifeless all-laser era.
The advantage of femtosecond LASIK laser is that laser cutting flaps are safe and accurate, and can use the high precision of excimer laser to complete various personalized surgical corrections, such as kappa angle compensation, Q value correction, high precise cutting guided by step aberration, high astigmatism, correction of presbyopia, etc. The disadvantage is that the surgical incision is relatively large.
Which surgery is better?
At present, the most commonly used surgical methods for laser surgery to correct myopia are SMILE (full femtosecond) and femtosecond LASIK (half femtosecond). So is full femtosecond necessarily better than half femtosecond?
The advantages of full femtosecond surgery are mainly small surgical incision and good corneal integrity after surgery, but the accuracy of surgical cutting is not as good as femtosecond LASIK, and femtosecond LASIK can also design various personalities according to the specific refractive characteristics of the patient's eyes in order to obtain better postoperative visual quality, femtosecond LASIK is currently the most widely used method of myopia surgery in the world.
Who is laser surgery suitable for?
If you want to have myopia laser correction surgery, generally you need to meet the following points:
●After strict preoperative examination and evaluation, other eye diseases, as well as corneal too thin, too high degree, etc., are clearly suitable for laser surgery.
●Age 18 to 50 years old; visual acuity is basically stable in the past two years, and the increase in myopia degree does not exceed 50 degrees every year.
● Usually within 1200 degrees of myopia, within 600 degrees of astigmatism, and within 600 degrees of hyperopia.
Preoperative evaluation and screening of laser surgery for myopia is very important. It is necessary to pass the examination to determine whether you are suitable for laser surgery.
How long does it take to regain vision after surgery?
Generally, you have to go back and close your eyes to rest on the day after the laser surgery. The doctor can temporarily wear contact lenses to relieve postoperative discomfort. Most patients can get a clear vision the next day, reaching 1.0, or even 1.2 or 1.5. , and some can even reach 2.0, the clear world is too beautiful.
However, after the operation, especially within one month after the operation, you must take good care of it, pay attention to rest, and take medicine on time. Don't stay up late to use your eyes, watch TV, use computers or read for too long, and reduce the use of electronic products, which plays a key role in the long-term vision effect in the later period.
Are there any sequelae of laser surgery?
Objectively speaking, any surgery will have sequelae and complications, so laser surgery is more or less a little bit.
●Dry eye: Many patients who have undergone surgery will have some symptoms of dry eye more or less after surgery. Depending on the individual situation, it may vary from a few days, a few weeks or a few months. Therefore, a full assessment of the patient's dry eye will be made before the operation. After the operation, the medication should be prescribed by the doctor. Symptoms can generally be effectively relieved.
●Glare: Some people say that driving at night after laser surgery will be affected, but this is actually a reaction of glare. Generally speaking, the higher the degree of myopia or the larger pupils, the more obvious the symptoms after surgery. But don't worry, most patients recover with ease.
In short, myopia laser surgery is not as scary as you think, and it is not as guaranteed for life as you think. Before receiving laser myopia correction surgery, detailed pre-operative preparation and inspection should be carried out. After surgery, it is necessary to avoid overuse of the eyes and avoid eye impact and trauma in order to enjoy a clear life.
