Enhanced predictability and axis precision of SMILE Pro, a retrospective analysis of myopic astigmatism correction

To evaluate three-month visual and refractive outcomes after small incision lenticule extraction (SMILE) Pro with the VISUMAX 800 femtosecond laser for myopic astigmatism correction and to compare results with previously reported VISUMAX 800 and VisuMax 500 outcomes.

Retrospective, observational clinical study. Records of 64 patients (128 eyes) who underwent SMILE Pro using the VISUMAX 800 laser (Carl Zeiss Meditec AG, Jena, Germany) between June and November 2024 were reviewed. Preoperative and 3-month postoperative data were analyzed in eyes with corrected distance visual acuity (CDVA) of 1.0 or better, including spherical equivalent (SE), refractive astigmatism, and vector analysis. Patients were classified into low (≤1.50 D) and high (>1.50 D) astigmatism subgroups.

The mean age of 64 patients (128 eyes) was 26.10±4.25y (19–36y). Attempted and achieved SE were strongly correlated (r=0.97, P<0.001). At 3mo, 36.7% and 87.5% of eyes were within ±0.50 and ±1.00 D of target refraction, respectively. Mean residual astigmatism was -0.56±0.27 D, lower in the low-astigmatism group (-0.39±0.23 D) than in the high group (-0.72±0.21 D; P<0.001). The mean absolute astigmatic angle of error was 4.47°±4.68°, with 97.6% ≤15°. No intraoperative or postoperative complications occurred.

SMILE Pro using the VISUMAX 800 femtosecond laser provides safe and predictable correction of myopic astigmatism with good axis alignment. However, the observed undercorrection in higher cylinders suggests that further optimization of astigmatic nomograms may improve refractive accuracy.