Abstract / Summary
Background and Objectives: Independent evidence on the longer-term performance of the Extend Bessel-optics intraocular lens remains limited. This study aimed to evaluate refractive and visual changes beyond the first postoperative year and to characterize binocular functional vision, defocus performance, and patient-reported outcomes 36–48 months after bilateral implantation. Materials and Methods: This ambispective, single-center case series included patients who had undergone bilateral implantation of the non-toric Extend IOL with emmetropic targets and had complete one-year postoperative data. One-year refraction and visual acuity data were retrieved retrospectively; eligible patients who had reached at least 36 months after surgery underwent prospective evaluation including refraction, visual acuity, defocus curves, pupillometry, VF-14, spectacle use, dysphotopsia, and satisfaction. Results: Of 37 patients in the source cohort, two lacked the required one-year postoperative visit. All 35 eligible patients (70 eyes) completed the prospective evaluation at 36–48 months. No statistically significant change in subjective spherical equivalent was detected (mean paired change, +0.029 D; 95% CI, −0.005 to +0.062 D; p = 0.114). Small statistically significant changes occurred in objective spherical equivalent (−0.052 D) and UDVA, UIVA, and UNVA (+0.009, +0.027, and +0.025 logMAR, respectively). Mean binocular defocus acuity remained ≤0.20 logMAR from +1.00 to −2.00 D, and the pooled monocular profile was compatible with a Partial-DOFi Extended functional classification. Mean VF-14 score was 98.9 ± 2.5; 94.3–97.1% of patients reported never using spectacles across viewing distances, and dysphotopsia was infrequent and predominantly mild. Conclusions: Subjective spherical equivalent showed no statistically significant change between one year and 36–48 months, whereas small statistically significant changes occurred in objective refraction and uncorrected visual acuity. Cross-sectional functional and patient-reported outcomes at 3–4 years were favorable in this selected cohort, which was characterized by relatively high implanted IOL powers.