During cataract surgery part of the front (anterior) capsule that holds the lens is removed. The clear back (posterior) capsule remains intact. As long as that capsule stays clear one has good vision. But in 10 to 30% of people, the posterior capsule loses its clarity. When this happens, an opening can be made in the capsule with a laser (posterior capsulotomy) to restore normal vision.
Before the laser procedure, the ophthalmologist does a thorough ophthalmic examination to make sure there is no other reason for vision loss.
A posterior capsulotomy is painless and takes a few minutes. Vision should improve within hours.
Potential but rare complications following laser posterior capsulotomy are increased intraocular pressure and retinal detachment.