Background
AFTER CATARACT
Presbyopia-correcting intraocular lenses (IOLs) are used to achieve independence from or reduce the dependence on spectacles after cataract surgery. With the use of bifocal IOLs, patients obtain uncorrected vision at both far and near distances but their visual acuity is often degraded at intermediate distances. Diffractive trifocal IOLs have been developed to demonstrate acceptable visual acuity from near to far distances by adding foci at near and intermediate distances [