Laser posterior capsulotomy, or YAG laser capsulotomy, is a noninvasive procedure performed on the eye to remove the opacification (cloudiness) that develops on the posterior capsule of the lens of the eye after extraction of a cataract. This differs from the anterior capsulotomy that the surgeon makes during cataract extraction to remove a cataract and implant an intraocular lens (IOL). Laser posterior capsulotomy is performed with Nd:YAG laser, which uses a wavelength to disrupt the opacification on the posterior lens capsule. The energy emitted from the laser forms a hole in the lens capsule, removing a central area of the opacification. This posterior capsule opacification (PCO) is also referred to as a secondary cataract.

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