title: Visual performance of four simultaneous-image multifocal contact lenses under dim and glare conditions.
abstract: OBJECTIVE
  To assess and compare the effects of four simultaneous-image multifocal contact lenses (SIMCLs), and those with distant-vision-only contact lenses on visual performance in early presbyopes, under dim conditions, including the effects of induced glare.
  
  
  METHODS
  In this double-masked crossover study design, 28 presbyopic subjects aged 40 to 46 years were included. All participants were fitted with the four different SIMCLs (Air Optix Aqua Multifocal [AOAM; Alcon], PureVision Multifocal [PM; Bausch & Lomb], Acuvue Oasys for Presbyopia [AOP; Johnson & Johnson Vision], and Biofinity Multifocal [BM; CooperVision]) and with monofocal contact lenses (Air Optix Aqua, Alcon). After 1 month of daily contact lens wearing, each subject's binocular distance visual acuity (BDVA) and binocular distance contrast sensitivity (BDCS) were measured using the Functional Visual Analyzer (Stereo Optical Co., Inc.) under mesopic conditions (3 candela [cd]/m) both with no glare and under the 2 levels of induced glare: 1.0 lux (glare 1) and 28 lux (glare 2).
  
  
  RESULTS
  Among the SIMCLs, in terms of BDVA, AOAM and PM outperformed BM and AOP. All contact lenses performed better at level without glare, followed by Glare 1, and with the worst results obtained under glare 2. Binocular distance contrast sensitivity revealed statistically significant differences for 12 cycles per degree (cpd). Among the SIMCLs, post hoc multiple comparison testing revealed that AOAM and PM provided the best BDCS at the three luminance levels. In both cases, BDVA and BDCS at 12 cpd, monofocal contact lenses outperformed all SIMCL ones at all lighting conditions.
  
  
  CONCLUSIONS
  Air Optix Aqua Multifocal and PM provided better visual performance than BM and AOP for distance vision with low addition and under dim conditions, but they all provide worse performance than monofocal contact lenses.
authors.affiliation: Optometry Research Group (GIO), Department of Optics, University of Valencia, Valencia, Spain.
authors.forename: Santiago
authors.initials: S
authors.lastname: García-Lázaro
authors.forename: Teresa
authors.initials: T
authors.lastname: Ferrer-Blasco
authors.forename: David
authors.initials: D
authors.lastname: Madrid-Costa
authors.forename: César
authors.initials: C
authors.lastname: Albarrán-Diego
authors.forename: Robert
authors.initials: R
authors.lastname: Montés-Micó
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D003261:Contact Lenses; D015350:Contrast Sensitivity / Q000502:physiology; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D019466:Glare; D006801:Humans; D008029:Lighting; D008297:Male; D008875:Middle Aged; D011305:Presbyopia / Q000503:physiopathology / Q000628:therapy*; D014792:Visual Acuity / Q000502:physiology