At present, the most minimally invasive myopia surgery is full femtosecond (smile), but if you want to do full femtosecond surgery, you must meet the following requirements:

1. Myopia should be in the range of 100 degrees to1000 degrees. If the degree is too low or too high, it is impossible to perform full femtosecond surgery. Semi-femtosecond surgery or other methods can be considered.

Astigmatism within 2.300 degrees (which can be achieved within 500 degrees by experienced doctors) can be corrected by full femtosecond, and it is recommended to consider semi-femtosecond or other methods when it exceeds 300 degrees.

3. In the last two or three years, the myopia degree has been basically stable, and the annual change is within 50 degrees. Full femtosecond surgery can be performed, and any refractive surgery is not recommended.

4. Corneal thickness should be within a safe range, because full femtosecond surgery needs to cut a lens in the middle of the cornea and take it out through a 2 mm incision, and the cornea will become thinner after surgery. The thickness of cornea should ensure that the thickness of the cut lens is greater than 20 microns, the total thickness of cornea after operation is greater than 380 microns, and the thickness of corneal stroma (the cornea is divided into five layers, the stroma layer accounts for 90%, and the lens is cut from the stroma layer in the middle) is greater than 280 microns. Of course, the corneal thickness of most people meets the requirements.

Some people have some eye diseases that need to be cured before full femtosecond surgery, such as mild lattice degeneration, pinhole, conjunctivitis and mild dry eye. If you need to use your eyes a lot in the near future, such as preparing for exams and writing papers, I suggest that you wait until this time has passed and then do surgery at a stage when your eyes are not tired, otherwise your vision will be unstable after the operation, which will affect your recovery.

Some people are not suitable for full femtosecond surgery, such as not cooperating with doctors during surgery; The head can't be straight; There are also diseases such as glaucoma, cataract, congenital corneal dystrophy and keratoconus. Others have been injured or operated on, and the cornea has scars, so they can't do full femtosecond surgery.