Myopia surgery is a widely performed surgical treatment for myopia, and many myopic patients have regained clear vision through surgery. However, myopia surgery is not as readily available as some rumors suggest, and not anyone can have myopia surgery. Before myopia surgery, a detailed and strict pre-operative examination will be performed (not the case in irregular hospitals), including computerized optometry, intraocular pressure measurement, corneal topography, subjective optometry, dilated pupil examination, fundus examination, anterior segment examination, corneal thickness measurement, eye A ultrasound, self-matching lens test, etc. Through the examination, we can know whether we are suitable for the surgery, the surgical plan, and the best post-operative visual acuity. The examination takes about 2 hours, and the surgery can be done on the second day at the earliest after the examination, not whenever you want, as some rumors say, and not immediately upon arrival at the hospital. In the preoperative examination, if myopia surgery is found to be contraindicated, then the surgery cannot be performed, including: 1, age less than 18 years old (except in special cases) or more than 50 years old; 2, refractive error in the last 2 years, the annual development of greater than 1.00D; 3, corneal thickness less than 450um; 4, eye with acute keratoconjunctivitis, corneal ulcers and other active inflammatory lesions; 5, have suffered from cone cornea 6.Patients with systemic diseases such as scarring, diabetes, collagen disease, etc.; 7.Pregnant women, drivers who drive at night for a long time; 8.Severe amblyopia with very poor corrected vision; 9.Patients with very high vision requirements and great concern about surgery; 10.Patients with mental illness and taking medication. These cases can not do myopia surgery, there are eye diseases need to be cured before surgery, incurable diseases can not be operated, in the regular hospital doctors will tell patients in detail related matters, for the patient after surgery safety responsibility. In contrast, irregular hospitals will operate on patients as long as they want to, regardless of whether the conditions are suitable or not. Patients must learn more about the relevant knowledge before deciding to operate, and choose a good and reliable hospital.