From the application of RK surgery in the early 1970s to the current femtosecond laser, in just over 30 years, corneal refractive surgery has undergone radical changes in terms of surgical approach, technical equipment, and design philosophy. And these changes can be described as rapidly changing, in terms of their own understanding, to several stages of development to elaborate. First, the stage of focusing more on the “effect” of surgery. RK surgery is hardly considered for refractive errors, so we will put it aside for now. PRK (excimer laser refractive keratomileusis) surgery has entered the golden age of keratomileusis, and the predictability, safety, and stability of PRK surgery is completely incomparable to RK surgery, and over time, keratomileusis has spread rapidly, and is highly sought after by ophthalmologists and myopic patients. At this time, people almost thought they had found the cure-all for myopia, so the volume of surgery rose dramatically and the number of myopia degrees corrected reached a record high, which is why there were frequent reports of PRK correcting high myopia and priding itself on correcting even higher myopia degrees. But the results of the surgery were really good at that time, and the postoperative vision improved very well, at least for a longer period of time after the surgery. Even in the early days of LASIK (excimer laser in situ keratomileusis), this philosophy still seemed to be somewhat “ingrained”. Secondly, there was a greater focus on the safety of the procedure. As people’s understanding of laser treatment of myopia deepened, as well as the amount of surgery and the passage of time, the initial “excitement” slowly degraded, PRK began to show its own shortcomings, early postoperative tearing, foreign body sensation and other irritating symptoms, slow recovery of vision, late postoperative HAZE and refractive regression. So LASIK was born, with virtually no irritation and no post-operative HAZE, and at the time, it was thought to solve almost all problems. Of course, there would be buts, as many ophthalmology gurus now say, LASIK to create a corneal flap was a double-edged sword, one side solved the problems brought by PRK, the other side brought new problems, a series of complications related to the corneal flap, which was the hottest topic in major ophthalmology magazines at the time. Most notably, the reports of postoperative posterior corneal bulging led to a renewed awareness and reflection, which would have been one of the reasons for the large number of negative reports on LASIK later. Is LASIK safe? was perhaps the common question of ophthalmologists and patients at that time. Corneal topography, especially topography that measures the anterior and posterior surfaces of the cornea (such as orbscan), made it possible to better understand a “disease” – preclinical cone cornea or subclinical cone cornea. Of course, the exact diagnosis of subclinical cone corneas varies, but if there is sufficient evidence to rule out subclinical cone corneas before surgery, then LASIK surgery is undoubtedly safe enough, and the residual stromal bed thickness after surgery becomes the “golden indicator” to ensure the safety of the surgery. In short, at this stage, safety is a big issue that we all have to pay attention to. Third, more attention to the postoperative visual quality of the stage. With the development of excimer equipment, keratome and inspection equipment, people seem to be less “concerned” about the effect and safety of keratomileusis, because these two pieces have been well solved and are no longer a big problem for us. At the same time, the application of wavefront aberration technology has given us a higher demand, not only for postoperative safety and clear vision, but also for clearer and more comfortable vision. From the initial dilated pupil examination to the later small pupil examination, whether it is Zernike, or Fourier, our goal, is to get more accurate data, the best post-operative results, and contrast sensitivity has become a higher requirement for detecting visual acuity. However, even now, we still have many questions that are not clear. How can we predict and compensate for the higher-order aberrations that arise during intraoperative and postoperative recovery? Or can we detect and correct them in real time? Are all higher-order aberrations even harmful? In addition, it seems that the development of excimer devices has not kept pace with the wavefront aberration, and although the intraoperative real-time tracking has made a qualitative leap forward, there is still a lot to go before we can achieve the so-called “hyperopia”. Although many shortcomings have been mentioned, wavefront aberration has indeed brought a great impact on the traditional surgical concept. It is undeniable that the quality of vision after individualized surgery guided by wavefront aberration has made a qualitative leap, especially in night vision. Fourth, the stage of more emphasis on biomechanics. In recent times, the focus of discussion has begun to shift to corneal biomechanics, and the return of the surgical approach to the surface is an excellent testimony to this. Reviewing the corneal base, the antitension of the cornea gradually decreases from the superficial to the deep stroma, and from the peripheral to the central cornea. Thinking more carefully about the surgical procedures and rationale for LASIK and surface cutting, it is clear that the biomechanical changes after surgery are greater in the former than in the latter, which makes it easy to understand the regression of surgical approaches (the difference between different surface procedures). I think it was Wilson who returned to the early days of PRK and LASIK. In the PRK period, even though there was a “feat” of pursuing the ultimate degree, there were very few reports of posterior corneal bulging, while in LASIK we were more “careful” and reports of posterior corneal bulging were common. Posterior bulging is frequently reported. Apart from the interference of patient and physician attention and examination equipment, this is still a strong indication of the problem. Although the debate over which is the more scientific approach is still not completely settled, it is certain that they are reason enough to forget about the once ultra-thin flap LASIK.