Some people do feel very satisfied with their vision at the time after cataract surgery, but after 0.5-1 year, or even longer, they will find that their vision gradually decreases again, and they think that it is a recurrence of cataract. This cannot be called a cataract recurrence, but is actually the most common complication of cataract surgery, due to the clouding of the cortex or lens epithelial cell proliferation that remains after surgery. Professionally, this is called posterior cataract, or clouding of the posterior capsule. The incidence of this type of clouding occurs more than three years after cataract surgery and can be as high as 30%-50%. In the case of childhood cataracts, it occurs in almost 100% of cases after surgery. When this posterior cataract affects vision, the posterior capsule of the lens in the pupil area can be incised with a laser, after which vision will be restored to its original state of clarity.