title: Prospective randomized trial of an anterior surface modified prolate intraocular lens.
abstract: OBJECTIVE
  We compare the contrast sensitivity obtained with an anterior surface modified prolate intraocular lens with the contrast sensitivity obtained with a standard spherical intraocular lens.
  
  
  METHODS
  Patients presenting for cataract surgery in one eye were randomized to receive either the Tecnis Z9000 intraocular lens (Pharmacia) or the AMO AR40e Opti-Edge intraocular lens (AMO). Sine wave grating contrast sensitivity testing under mesopic and photopic conditions served as the principal outcome measure.
  
  
  RESULTS
  The Tecnis Z9000 intraocular lens provided statistically significantly better contrast sensitivity at 1.5 and 3 cycles per degree under mesopic conditions and at 6, 12 and 18 cycles per degree under photopic conditions.
  
  
  CONCLUSIONS
  The use of a modified prolate intraocular lens during cataract surgery has the potential to improve contrast sensitivity under both mesopic and photopic conditions.
authors.affiliation: Oregon Eye Institute, Oregon Health & Science University, Portland, OR, USA. mpacker@finemd.com
authors.forename: Mark
authors.initials: M
authors.lastname: Packer
authors.forename: I Howard
authors.initials: IH
authors.lastname: Fine
authors.forename: Richard S
authors.initials: RS
authors.lastname: Hoffman
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Piers
mesh_terms: D000368:Aged; D002387:Cataract Extraction; D015350:Contrast Sensitivity; D004867:Equipment Design; D006801:Humans; D007910:Lenses, Intraocular; D011184:Postoperative Period; D011446:Prospective Studies; D016896:Treatment Outcome; D014792:Visual Acuity