After-cataract refers to a special state in which the lens cortex remains or a fibrous membrane forms in the pupil area after the cataract is surgically removed or the cortex of a traumatic cataract is partially absorbed. This complication is particularly common and serious in early intraocular lens implantation surgery when the importance of lens epithelial cells and cortex removal is not yet clear. Even in the 1990s, this complication was still a major clinical problem after ECCE combined with posterior chamber intraocular lens implantation, with an incidence rate as high as 25% to 50%. The structure and morphology of posterior capsule opacification are very complex, mainly related to the amount of residual cortex after surgery, the presence or integrity of the posterior capsule, and the severity of the postoperative inflammatory response.