Purpose: To compare new-generation multifocal intraocular lenses (IOLs) with monofocal IOLs.
Design: Randomized prospective clinical trial.
Participants: Sixty-two consecutive patients with cataract, seen between January of 2005 and January of 2006 at the Department of Ophthalmology of Palermo University Hospital in Italy, were bilaterally implanted with monofocal (AR 40, Advanced Medical Optics [AMO], Santa Ana, CA; 15 patients), multifocal refractive (Array SA40N, AMO; 16 patients), multifocal refractive (ReZoom, AMO; 15 patients), or multifocal diffractive pupil-independent (Tecnis ZM900, AMO; 16 patients) IOLs.
Intervention: Bimanual phacoemulsification.
Main outcome measures: Primary outcomes were far, near, and intermediate visual acuity of the 4 IOL-implanted groups. Secondary outcomes were defocusing curves, contrast sensitivity, patients' quality of life (7-item visual function questionnaire [VF-7], halos and glare presence, overall satisfaction), and spectacle independence. Snellen visual acuity was measured as uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), uncorrected near visual acuity (UCNVA), best distance corrected near visual acuity (BDCNVA), best corrected near visual acuity (BCNVA), uncorrected intermediate visual acuity (UCIVA), and best distance corrected intermediate visual acuity (BDCIVA).
Results: UCNVA was 20/50 in the monofocal IOL group, compared with 20/32 or better in the multifocal IOL groups (P<0.0005). The monofocal IOL group exhibited a lower BDCNVA than the multifocal IOL groups (P<0.0005). The diffractive multifocal IOL group performed better than either refractive group (P = 0.007). UCIVA was significantly different (P = 0.001) among the groups: monofocal (AR 40) 20/32; multifocal refractive (Array SA40N) 20/30; multifocal refractive (ReZoom) 20/25; and multifocal diffractive (Tecnis ZM900) 20/30. Defocusing curves with -3.00 diopter lens exhibited a better trend in the diffractive group. The refractive multifocal IOL groups exhibited lower contrast sensitivities at 3 cycles/degree (P = 0.038). The VF-7 mean score was significantly lower in the monofocal than the multifocal IOL groups (P = 0.002). Night halos were more common in the refractive groups (P<0.01). Spectacle independence was 20% in the monofocal IOL group, 43.7% and 53.3% in the refractive multifocal IOL groups, and 87.5% in the diffractive multifocal IOL group (P<0.05).
Conclusions: Multifocal IOLs provide a greater depth of focus and higher patient satisfaction, and make intermediate and near visual tasks easier than do monofocal lenses. New-generation, diffractive, pupil-independent multifocal IOLs provide better near vision, equivalent intermediate vision, less unwanted photic phenomena, and greater spectacle independence than either monofocal or refractive multifocal IOLs.