What is AK surgery? AK surgery is astigmatism release surgery. Traditional AK surgery uses a metal knife to cut on the cornea, thus loosening the cornea and playing a role in correcting astigmatism. The femtosecond AK surgery we are performing now is able to perform precise femtosecond incision and release at the location of high corneal curvature through precise femtosecond laser technology, thus achieving precise and effective results. For whom is it suitable? AK surgery is suitable for patients with simple large astigmatism or myopia or hyperopia combined with large astigmatism, who cannot resolve all degrees with excimer laser, who cannot tolerate rigid corneal contact lenses (RGP), and who do not want to wear glasses. The advantages are: 1, no age limit, more than 10 years old, can cooperate with the surgery; 2, no cutting corneal tissue, little impact on corneal stability, can secondary excimer laser correction of future refractive error; 3, precise, controllable, good results.