Major complications are as follows: Serious complications: Zhang Jian, Ophthalmology, Xuanwu Hospital, Capital Medical University 1. Infection, endophthalmitis: 1/4000; 2. Corneal loss of compensation: varies among surgeons, <1/10,000, requires reoperation for corneal transplantation; 3. Lens nucleus subsidence: varies among surgeons, about 1/4000, hard nucleus occurs, cured by reoperation; 4. IOL position shift: 1/1000, cured by reoperation Common complications: 1. intraoperative posterior capsule rupture: 1-5%, requiring second surgery for IOL implantation; 2. corneal edema: about 10%, cured by medication; 3. posterior cataract: 5%, occurs more often in young patients, cured by laser; 4. transient IOP elevation: 3%, cured by medication; 5. inflammatory reaction: cured by medication; 6. dry eye: common in the early postoperative period, most of them recover after stopping medication The percentage of the above complications is related to the individual conditions of different cataract patients, surgeon's experience and surgical conditions, and so on, and the specific situation varies.