Refractive lens exchange with the Acri.Twin asymmetric diffractive bifocal intraocular lens system.

Purpose: To evaluate efficacy, safety, and predictability after refractive lens exchange (RLE) in patients who had implantation of asymmetric Acri.Twin bifocal diffractive intraocular lenses.

Methods: The study comprised 130 eyes of 65 consecutive patients after RLE who had bilateral implantation of the Acri.Twin system. Eyes were divided into myopic and hyperopic groups. Binocular uncorrected distance visual acuity, best-corrected distance visual acuity (BCVA), uncorrected distance near visual acuity, and best distance-corrected near visual acuity (BCNVA) were recorded preoperatively and 6 months after surgery.

Results: Efficacy indexes were 0.99 for myopic and 0.93 for hyperopic patients at 6 months postoperatively. No patients lost >2 lines of BCVA. For the myopic group, 6 patients gained 1 line, and 10 patients gained >or=2 lines; for the hyperopic group, 5 patients gained 1 line, and 6 patients gained >or=2 lines. Safety indexes were 1.13 and 1.03 for myopic and hyperopic patients, respectively. No patients lost >or=2 lines of BCNVA; for the myopic group, only 2 patients lost 1; for the hyperopic group there was no change after surgery. Safety indexes at near were 0.99 for myopic and 1.00 for hyperopic patients. Efficacy indexes at near were 1.05 for myopic and 1.07 for hyperopic patients.

Conclusions: RLE with asymmetric bilateral implantation of the Acri.Twin bifocal IOL is an effective procedure for correcting ametropia and presbyopia. Results obtained were safe and effective at distance and near for both myopic and hyperopic patients.