title: Visual performance with simultaneous vision multifocal contact lenses.
abstract: OBJECTIVE
  The aim was to assess visual performance after PureVision high addition multifocal contact lens (PM) fitting through contrast sensitivity measured under different illumination levels for both distance and near.
  
  
  METHODS
  In a cross-over study, 20 presbyopic patients were randomly assigned to PM or spectacles. Near contrast sensitivity was measured with the Vistech VCTS 6500 system. Distance contrast sensitivity and distance visual acuity (VA) were measured with the Functional Vision Analyser under photopic (85 cd/m(2) ) and mesopic (3.0 cd/m(2) ) conditions, the latter also under two levels of induced glare: 1.0 lux and 28 lux. Near VA was measured by logMAR charts under approximately 80 cd/m(2) luminance settings.
  
  
  RESULTS
  Average monocular spectacle corrected and PM VA were -0.02 ± 0.05 and 0.03 ± 0.05 logMAR for distance photopic, 0.16 ± 0.10 and 0.23 ± 0.07 logMAR for distance mesopic and -0.03 ± 0.05 and 0.05 ± 0.06 logMAR for near photopic, respectively. Average binocular spectacle corrected and PM VA were -0.05 ± 0.07 and -0.01 ± 0.03 logMAR for distance photopic, 0.10 ± 0.06 and 0.18 ± 0.05 logMAR for distance mesopic and -0.08 ± 0.06 and 0.02 ± 0.05 logMAR for near photopic, respectively. Statistically significant differences were found between the contrast sensitivity with the two types of correction for both distance and near, with spectacle correction being better in all cases.
  
  
  CONCLUSIONS
  PureVision multifocal contact lenses preserve good VA and good visual performance under real-life conditions.
authors: Optometry Research Group, Department of Optics, University of Valencia, Dr. Moliner 50, Burjassot, Valencia, Spain.
authors: Almudena
authors: A
authors: Llorente-Guillemot
authors: Santiago
authors: S
authors: García-Lazaro
authors: Teresa
authors: T
authors: Ferrer-Blasco
authors: Rafael J
authors: RJ
authors: Perez-Cambrodi
authors: Alejandro
authors: A
authors: Cerviño
mesh_terms: D000065:Accommodation, Ocular / Q000502:physiology*; D000328:Adult; D003261:Contact Lenses; D015350:Contrast Sensitivity / Q000502:physiology*; D018592:Cross-Over Studies; D004867:Equipment Design; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D011305:Presbyopia / Q000503:physiopathology* / Q000628:therapy; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology*