The indications for laser surgery are 100-1200 degrees of myopia and less than 600 degrees of astigmatism. Generally the higher the degree, the greater the risk of refractive regression after surgery, such as when myopia exceeds 900 degrees, there may be about 100-200 degrees of myopia regression after surgery. If the patient is more than 600 degrees of myopia, the amount of cutting and corneal consumption is relatively large. If the amount of corneal residual retained after surgery is relatively small, the patient may not be able to tolerate the intraocular pressure and may easily form the danger of cone cornea, which may cause serious impact on vision. In addition, patients with thin corneal thickness and high myopia are equally unsuitable for myopic laser surgery. In addition, before undergoing laser eye surgery, patients need to be checked for corneal thickness, corneal curvature, anterior chamber depth, intraocular pressure, fundus status and refractive error to determine if they can undergo surgery.