Comparison of Stereoacuity Across Distances in Bilateral Intraocular Lens Implantation: Monofocal versus Diffractive Multifocal Lenses.

Purpose: To evaluate stereopsis at various distances after bilateral implantation of multifocal and monofocal intraocular lenses (IOLs). Patients and Methods: This study included 173 patients who underwent cataract surgery, with 70 receiving bilateral multifocal and 103 receiving bilateral monofocal IOLs. Stereoacuity was assessed without correction in the multifocal group and with correction in the monofocal group at far, intermediate, and near distances. Age-matched comparisons were conducted as the mean age was low in the multifocal group. Stereoacuity was assessed at 0.3, 0.5, 0.7, 3, and 5 m using a Binoptometer 4P. Results: Stereoacuity was significantly better in the multifocal group than in the monofocal group at all distances (p < 0.05), except at 0.3 and 5 m after age matching. The proportion of patients achieving 100 arcsec or better was significantly higher in the multifocal group than in the multifocal group at all distances except 0.3 m (p < 0.05). Additionally, significant differences were noted only at 0.7 m after age matching (p < 0.05). The proportions of patients unable to identify 600 arcsec in the multifocal, monofocal, and age-matched monofocal groups were 3%, 11%, and 11% at 0.3 m; 0%, 9%, and 14% at 0.5 m; 0%, 9%, and 8% at 0.7 m; 0%, 5%, and 3% at 3 m; and 0%, 6%, and 6% at 5 m, respectively. After age matching, poor stereopsis was significantly reduced in the multifocal group at 0.5 m (p < 0.05) but not at 0.7 m. Conclusion: Patients with bilateral implanted multifocal IOLs exhibited superior stereopsis across various distances than those with bilateral monofocal IOLs. Additionally, fewer patients with multifocal IOLs experienced poor stereopsis. These results suggest that multifocal IOLs may help patients in maintaining stereopsis by facilitating focus on multiple points from far to near distances daily.