Abstract:
Our purpose was to evaluate near stereoacuity (SA) with Focus Progressives and PureVision Multifocal simultaneous vision contact lenses. In a cross-over study design, 20 presbyopic subjects were fitted with either the Focus Progressives or PureVision Multifocal lenses. After 1 month, SA was measured with the vectographic Titmus, Random dot stereotests, and the Howard-Dolman apparatus under photopic conditions (85 lux) at 40 cm. Binocular high-contrast visual acuity at distance and near was examined. Subjects were then refitted with the alternative correction and the procedure was repeated. Mean SA with the Focus Progressive was 21 +/- 7 sec arc, 54 +/- 17 sec arc, and 51 +/- 21 sec arc, with the Howard-Dolman, Titmus, and Random dot sterereotests, respectively. These values were 25 +/- 9 sec arc, 74 +/- 26 sec arc, and 82 +/- 26 sec arc with the PureVision Multifocal, respectively. SA was better with the Focus Progressives compared with the PureVision using the Howard-Dolman (4 sec arc of difference; p = 0.001), Titmus (2 sec arc of difference; p = 0.001), and Random dot (31 sec arc of difference; p < 0.001) tests. Binocular mean high-contrast distance visual acuity was similar for the Focus Prog...