The effect of add power on distance vision with the acuvue bifocal contact lens.
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.
Ardaya
David
D
Pacific University, College of Optometry, Forest Grove, Oregon 97116, USA.
DeVuono
Giulia
G
Lin
Ivy
I
Neutgens
Annie
A
Bergenske
Peter
P
Caroline
Patrick
P
Smythe
Jennifer
J
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*