title: Comparison of a diffractive bifocal and a monofocal intraocular lens.
abstract: OBJECTIVE
  To compare a Pharmacia diffractive bifocal intraocular lens (IOL) with a monofocal lens of the same design without the diffractive grating.
  
  
  METHODS
  Multicenter study.
  
  
  METHODS
  This randomized, prospective study comprised 70 patients with a monofocal IOL and 79 with a diffractive bifocal IOL. Follow-up was 5 to 6 months. Near and distance visual acuities, contract sensitivity, patient satisfaction, and spectacle use were evaluated.
  
  
  RESULTS
  All patients achieved a best corrected visual acuity of 0.5 or better; 80% in the monofocal and 71% in the bifocal group had a best corrected visual acuity of 1.0 or better. Without correction, 93% of the bifocal and 9% of the monofocal group could read J3 or better. With distance correction, 99% and 4%, respectively, could read J3 or better. Contrast sensitivity was slightly lower in the bifocal group at distance and near for all spatial frequencies. In the bifocal group, 46% never used spectacles for near tasks. Overall satisfaction was rated good by 86% of the monofocal and 85% of the bifocal group.
  
  
  CONCLUSIONS
  The diffractive bifocal IOL performed well at distance and near. Patients who no longer require spectacles will benefit significantly from a bifocal IOL, but many with a bifocal IOL in one eye will require spectacles for the fellow eye.
authors: Sunderland Eye Infirmary, England.
authors: E D
authors: ED
authors: Allen
authors: R L
authors: RL
authors: Burton
authors: S K
authors: SK
authors: Webber
authors: E
authors: E
authors: Haaskjold
authors: K
authors: K
authors: Sandvig
authors: H
authors: H
authors: Jyrkkiö
authors: E
authors: E
authors: Leite
authors: A
authors: A
authors: Nyström
authors: J
authors: J
authors: Wollensak
mesh_terms: D000368:Aged; D002386:Cataract / Q000503:physiopathology; D002387:Cataract Extraction; D015350:Contrast Sensitivity / Q000502:physiology*; D005139:Eyeglasses; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007910:Lenses, Intraocular; D008297:Male; D017060:Patient Satisfaction; D011446:Prospective Studies; D014792:Visual Acuity / Q000502:physiology*