Posterior capsule opacification (PCO) is a physiological postoperative consequence of an uneventful uncomplicated extracapsular cataract surgery. Capsular opacification is different from the intraoperative opacification that takes place in the intact lenses. It is known as a plaque that can either be in the anterior and/or posterior capsule.PCO referred to as 'secondary cataract' or 'after cataract', develops over the clear posterior capsule a few months to a few years after an uneventful cataract surgery. Figure 1 shows various forms of capsular opacification. PCO results from the growth and abnormal proliferation of lens epithelial cells (LECs) on the capsule at the time of cataract surgery.
Central PCO obscuring the visual axis can be treated with either surgical intervention, such as posterior capsule scraping or with a nonsurgical Nd:YAG laser capsulotomy.