Table 1 Technical characteristics and sample size of corneal refractive surgery for cutting

LASIK

It uses a microkeratome to make a pedicled lamellar corneal flap with a diameter of 8\(^{\sim }\)10mm and a thickness of 130\(^{\sim }\)160um. An excimer laser is used to cut a concave surface with a certain diopter on the stromal bed, and then the corneal flap is reset. By changing the corneal front the curvature of the surface achieves the purpose of correcting myopia [43].

9096

PRK

There is no need for a mechanical blade or ethanol to remove the corneal epithelium. The laser directly cuts the epithelium and stromal layer on the corneal surface, and no flap is required during the operation [44].

1991

SMILE

First, a femtosecond laser is used to create a lens in the corneal stroma, then a tiny incision is made to avoid the creation of a corneal flap, and finally, the corneal stromal lens tissue is separated in a small incision of 2-5mm [45].

2636