title: The effect of add power on distance vision with the acuvue bifocal contact lens.
abstract: OBJECTIVE
  This study was designed to determine if subjective evaluation of quality of distance vision with the Acuvue Bifocal contact lens could be correlated with high- and low-contrast acuity scores.
  
  
  METHODS
  LogMAR visual acuities of 20 non-presbyopic subjects were measured using high and low-contrast Bailey-Lovie charts. Each subject wore an Acuvue Bifocal contact lens with add powers +1.00, +1.50, +2.00, and +2.50, each optimized for best distance acuity.
  
  
  RESULTS
  Subjects showed significantly decreased acuities with increasing add; a low-contrast target heightened this effect. Subjects reported a reduction in quality of distance vision, increasing fluctuation, ghosting/shadows, and halos around lights that correlated with increasing add power.
  
  
  CONCLUSIONS
  Our findings suggest that the Acuvue Bifocal contact lens may be expected to perform best for presbyopes with low-to-moderate bifocal add requirement, and that clinicians should anticipate decreased low-contrast acuity and reduced overall quality of vision as add powers are increased.
authors.affiliation: Pacific University, College of Optometry, Forest Grove, Oregon 97116, USA.
authors.forename: David
authors.initials: D
authors.lastname: Ardaya
authors.forename: Giulia
authors.initials: G
authors.lastname: DeVuono
authors.forename: Ivy
authors.initials: I
authors.lastname: Lin
authors.forename: Annie
authors.initials: A
authors.lastname: Neutgens
authors.forename: Peter
authors.initials: P
authors.lastname: Bergenske
authors.forename: Patrick
authors.initials: P
authors.lastname: Caroline
authors.forename: Jennifer
authors.initials: J
authors.lastname: Smythe
mesh_terms: D000328:Adult; D003263:Contact Lenses, Hydrophilic; D015350:Contrast Sensitivity / Q000502:physiology*; D004311:Double-Blind Method; D006801:Humans; D017755:Prosthesis Fitting; D012029:Refraction, Ocular; D014792:Visual Acuity / Q000502:physiology*