Visual performance with multifocal corneal gas-permeable contact lenses in young adults: A pilot study

To evaluate the performance of four experimental multifocal gas permeable contact lens (MFGPCL) designs and their impact on visual function in young adults. Seventeen young adults (age, 23.17 ± 4.48 years) enrolled in the study. Each participant was randomly assigned to wear two of four MFGPCL designs. They wore the first type of the assigned lens binocularly for one week and, after one week of washout period, wore another design on both eyes for another week. The four MFGPCL designs were as follows: design A (distance zone [DZ] 1.5 mm / add 3.0 D), B (DZ 1.5 mm / add 1.5 D), C (DZ 3.0 mm / add 3.0 D), and D (DZ 3.0 mm / add 1.5 D). Baseline visual acuity, contrast sensitivity function, and accommodation data were collected at baseline and repeated after one week of MFGPCL daily wear. Distance and near visual acuities were not significant affected with the four MFGPCL designs. Contrast sensitivity was significantly lower in design A across all measured spatial frequencies (p < 0.05), with no significant impact from other designs on all frequencies. No significant effect was observed on accommodation measured at 33 cm (p > 0.05). Three of the investigated MFGPCL designs preserve satisfactory visual performance. Lens design A incorporated with higher add and smaller center zone diameter had a stronger impact on the visual performance.