Comparison of visual quality after monocular and binocular trifocal intraocular lens implantation during cataract...

To evaluate visual quality in patients undergoing monocular or bilateral cataract surgery with trifocal intraocular lens (IOL) implantation.

We conducted a single-center, prospective, observational research.This study included 62 eyes of 31 patients who received trifocal IOL implantation in one eye only (observation group), and 62 eyes of 31 patients who received bilateral trifocal IOL implantation (control group).Three months postoperatively, monocular and binocular distance, intermediate, and near visual acuity, modulation transfer function (MTF), Strehl ratio (SR), total ocular higher-order aberrations, and three-level visual function were assessed. A questionnaire was used to evaluate spectacle independence, light disturbance, overall satisfaction, and quality of life.

Both groups demonstrated significant improvement in mean monocular uncorrected distance visual acuity (UDVA) in the operated eyes postoperatively (P < 0.05). No statistically significant differences were observed between the two groups in mean monocular UDVA of the surgical eyes, binocular distance, intermediate, and near visual acuity, MTF, SR, total ocular higher-order aberrations, coma, trefoil, spherical aberration, VF-14-CN scores, or satisfaction questionnaire scores (P > 0.05). However, three-level visual function was significantly better in the control group than in the observation group (P < 0.05). Simultaneous vision positively correlated with differences in total ocular higher-order aberrations; fusion vision positively correlated with the difference in uncorrected intermediate visual acuity (UIVA) (r = 0.410, P = 0.027). Stereopsis positively correlated with differences in binocular UIVA (r = 0.545, P = 0.002) and binocular uncorrected near visual acuity (UNVA) (r = 0.474, P = 0.009). Multivariate linear regression analysis showed that when the difference in bilateral UIVA exceeded 0.439, patients demonstrated abnormal fusion vision; when the difference exceeded 0.472, stereopsis was absent.

Patients with either monocular or bilateral trifocal IOL implantation achieved good postoperative visual quality. However, those in the control group exhibited superior three-level visual function. A bilateral UIVA difference greater than 0.439 impaired binocular fusion, and a difference greater than 0.472 eliminated stereopsis.