Excimer myopic refractive surgery is now a very mature surgery, with the continuous improvement of technology, the scope of surgery is getting bigger and bigger, but there are still some cases that should be operated with caution. 1, active eye diseases in both eyes, including acute conjunctivitis, keratitis, severe corneal scarring, uveitis, glaucoma and fundus diseases, these diseases themselves will affect the results of excimer surgery, while increasing the risk of surgery, and the post-operative treatment and examination of the original disease also have different degrees of impact. 2, cone corneal As the corneal refractive surgery is mainly performed on the cornea, the normal shape of the cornea is especially important for the surgery. If there is a cone cornea, it is an absolute contraindication to the surgery, or some patients have a risk of cone cornea, the chance of cone cornea will be greatly increased after the surgery. 3, super high myopic patients super high myopic patients generally refers to myopia in more than 1000 degrees, excimer laser surgery generally the higher the degree of cutting corneal tissue, the less the remaining corneal tissue will increase the risk of cone corneal after surgery, while in order to reduce the amount of cutting surgery will try to choose a smaller light area, the post-operative visual quality will be affected to varying degrees. Therefore, for highly myopic patients, it is generally recommended to implant a crystalline IOL (ICL), which not only ensures high-definition visual effects after surgery, but also completely avoids corneal complications. 4.Patients with thin corneas Some patients have low myopia, good corrected vision and normal corneal morphology, but cannot undergo surgery due to their relatively thin corneas. For such patients, they can choose ICL surgery, which still works well and avoids corneal damage. Therefore, refractive surgery itself is a very safe surgery with immediate results. As long as you grasp the indications for the surgery and choose the right surgery for you, you will not only be able to remove your glasses permanently and enjoy a clear and bright world after the surgery, but also the results will be long-lasting and stable.