Visual performance of a multi-zone bifocal and a progressive multifocal contact lens.
OBJECTIVE
This study measured the relative visual performance of two planned-replacement soft contact lenses for presbyopic correction: a multi-zone bifocal (ACUVUE, Johnson & Johnson Vision Care, Jacksonville, FL) contact lens and a progressive multifocal (Focus Progressives, CIBA Vision, Duluth, GA) contact lens.


METHODS
This was a randomized, double-masked, non-dispensing cross-over study. Visual performance was evaluated by log of minimal angle of resolution (LogMAR) measurement of visual acuity (VA) under a representative range of luminances (distance 250 candela[cd]/m2 and 2.5 cd/m2, near 250 cd/m2 and 50 cd/m2) and contrasts (90% and 10%). The 45 presbyopic subjects were equally distributed in three subgroups according to spectacle addition: low presbyopia (+0.75D to +1.25D); medium presbyopia (+ 1.50D to + 1.75D); and high presbyopia (+2.00 to +2.50D).


RESULTS
Statistically significant differences were found in overall distance VA (P<0.001; average of four luminance-contrast combinations) and low-luminance distance VA (P=0.004), which, in both cases, favored the multi-zone bifocal lens design. For low presbyopes, the multi-zone bifocal design produced a significantly better visual performance (P=0.004) than did the progressive multifocal. Overall near VA was also significantly better (P<0.001) with the multi-zone bifocal lens. Differences in near VA were particularly marked in high-luminance conditions (high and low contrasts combined) and were statistically significant for all three presbyopic subgroups.


CONCLUSIONS
Visual acuity performance with the multi-zone bifocal was superior overall to that achieved with the progressive multifocal design. This study suggests that having only one addition is detrimental to performance with the progressive multifocal lens, particularly for low presbyopes.
Guillon
Michel
M
Contact Lens Research Consultants, London, UK. mguillon@otg.co.uk
Maissa
Cecile
C
Cooper
Philip
P
Girard-Claudon
Karine
K
Poling
Timothy R
TR
D000328:Adult; D000368:Aged; D003261:Contact Lenses; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004867:Equipment Design; D006801:Humans; D008029:Lighting; D008875:Middle Aged; D011305:Presbyopia / Q000503:physiopathology* / Q000534:rehabilitation*; D015348:Vision, Binocular; D014785:Vision, Ocular; D014792:Visual Acuity