Expanding Horizons: Visual Outcomes with a 7.7 mm Optical Zone in KLEx Surgery.

Abstract

Purpose: To evaluate the visual and corneal outcomes of Keratorefractive Lenticule Extraction (KLEx) using a large lenticule diameter with a 7.7 mm optical zone and 7.9 mm cap diameter. The study aimed to determine the feasibility, refractive precision, and potential benefits of larger optical zones in improving visual quality and reducing myopic regression, particularly in patients with larger scotopic pupils.

Methods: This retrospective case series included 40 eyes from 20 patients who underwent KLEx surgery with the VisuMax800 femtosecond laser. The programmed lenticule diameter was 7.7 mm, and the cap diameter was 7.9 mm, with a cap thickness of 140 µm and a 2.5 mm incision. Preoperative spherical equivalents ranged from - 1.5 D to - 4.75 D. Postoperative evaluations were conducted at 3 months, and assessed refractive outcomes, uncorrected visual acuity (UCVA), and residual astigmatism. Surgical planning was based on a personalized nomogram with refractive adjustments for low astigmatic values.

Results: At 3 months, 100% of eyes achieved a UCVA of 20/20, and 25% reached 20/16 or better. The mean postoperative spherical equivalent was + 0.14 ± 0.27 D. Refractive predictability was high, with 97.5% of eyes within ± 0.5 D of intended spherical correction and 90% within ± 0.5 D of cylindrical correction. Residual astigmatism was ≤ 0.50 D in 87% of cases. No adverse events were reported.

Conclusions: KLEx using large lenticules is safe, effective, and highly accurate. Larger optical zones may enhance refractive stability and visual quality in patients with large pupils.