Comparison Of Astigmatic Correction Outcomes With Trifocal Toric Iols Using Image-Guided System Vs. Laser-Assisted Capsulorhexis Marking Systems

To compare postoperative residual astigmatism and demographic/refractive characteristics in cataract patients receiving trifocal  toric intraocular lenses (IOLs) (FineVision; PhysIOL, Liege, Belgium) implanted with guidance by either the image-guided system (Callisto eye; Carl Zeiss, Oberkochen, Germany)  or the robotic femtosecond laser refractive capsulorhexis marking system (ALLY's IntelliAxis; LENSAR, Orlando, FL).

This is a retrospective study conducted at Medicana Zincirlikuyu Hospital, Istanbul, Turkey.

This study was conducted including 26 eyes of 18 patients who underwent cataract surgery with trifocal toric IOL implantation. Eyes were divided into two groups: Callisto group (n=10 eyes) and LENSAR group (n=16 eyes). Preoperative biometric data and postoperative refractive outcomes were analyzed. The primary outcome measure was postoperative residual cylinder. Secondary outcomes included postoperative spherical equivalent, uncorrected visual acuity (UCVA), and best-corrected visual acuity (BCVA). Between-group comparisons were performed using independent samples t-test for normally distributed data (Shapiro-Wilk test) and Mann-Whitney U test for non-normally distributed data. Statistical significance was set at p<0.05.

The LENSAR group demonstrated statistically significantly lower postoperative residual astigmatism compared to the Callisto group (mean |CYL|: 0.27 ± 0.32 D vs. 0.54 ± 0.34 D; Mann-Whitney U, p=0.030). A higher proportion of LENSAR eyes achieved residual cylinder ≤0.50 D (93.8% vs. 85.7%). No statistically significant difference was found in postoperative sphere or residual SEQ between the two groups. The only significant preoperative difference was in white-to-white diameter (WTW; p=0.032) and sex distribution (p=0.044), while all other biometric parameters were comparable.

Both the Callisto Eye and LENSAR robotic laser-assisted systems achieved good astigmatic correction with multifocal toric IOLs in cataract patients. However, eyes in the LENSAR group showed statistically significantly lower postoperative residual cylinder (p=0.030), with a higher proportion achieving the target of ≤0.50 D residual astigmatism. These results suggest that the LENSAR robotic femtosecond laser platform may confer an advantage in astigmatic correction precision for toric IOL implantation. Prospective studies with larger sample sizes and matched cohorts are warranted to confirm these findings.