Visual performance of a non-diffractive extended depth of focus IOL in stable early-stage Keratoconus: prospective pilot study

Abstract

To evaluate visual performance, contrast sensitivity (CS), optical quality, and subjective satisfaction of Vivity extended depth-of-focus (EDOF) premium intraocular lens (pIOL) in early keratoconus (KC). In this prospective, interventional, single-center clinical study, ten patients with mild bilateral KC and cataract received AcrySof IQ Vivity pIOL. Pre- and postoperative assessments included monocular and binocular uncorrected and distance-corrected visual acuities at 4 m (UDVA, DCVA), uncorrected and distance-corrected intermediate and near visual acuities at 66 cm (UI66VA, DCI66VA) and 40 cm (UNVA, DCNVA), defocus curve, CS, wavefront aberrometry (RMS, PSF, Strehl ratio), halometry, and subjective outcomes. At 3 months, mean ± SD monocular DCVA in the dominant eyes (primary endpoint) was 0.06 ± 0.13 logMAR. A statistically significant improvement was observed between preoperative and postoperative monocular and binocular UDVA, UNVA, DCNVA (p < 0.001), and DCVA (p = 0.03). Binocular DCI66VA and UI66VA were 0.10 ± 0.15 and 0.14 ± 0.16 logMAR, respectively. The defocus curve was ≤ 0.20 logMAR from + 0.50 D to – 2.00 D. CS peaked under scotopic conditions at 6 cpd, total ocular RMS improved from 2.15 ± 1.98 to 1.09 ± 0.77 (p = 0.09). NEI-RQL-42 scores indicated favourable patient-reported outcomes, particularly for glare, clarity of vision, and satisfaction with correction. In this small prospective pilot study, bilateral implantation of a non-diffractive EDOF IOL was associated with favourable short-term visual outcomes in highly selected patients with stable early keratoconus. These preliminary findings suggest that early stable KC may not represent an absolute contraindication to non-diffractive EDOF IOL implantation, but larger comparative studies with longer follow-up are required.