ICL, known as Implantable Contact Lens, is a safe and effective alternative for refractive surgeons and patients to correct high myopia. ICL has become the first choice for patients who are unable to undergo LASIK or LASEK surgery due to corneal problems, dry eyes, and high myopia. The advantages of ICL: 1, correction of a wider range of refractive error: myopia 50 degrees ~ 1800 degrees, astigmatism 50 degrees ~ 600 degrees. 2, safe and reversible: no cutting corneal tissue, can be removed or replaced if necessary. 3, UV protection: better protection of the eyes. The new generation of Visian ICL (V4c) was launched in Europe in April 2011 and entered China in October 2014. It uses central hole technology, which eliminates the need for periradicular iris cutting and brings greater convenience to doctors and patients, and its safety, effectiveness, predictability and stability have been confirmed by a large body of literature. Pre-operative eye examination is a critical and important step in the success of ICL surgery. Patients are advised to make an appointment for surgery after a thorough examination at a hospital you rely on and to have regular standardized post-operative follow-ups.