# Enhanced astigmatism correction accuracy with image-guided toric ICL implantation: a comparative clinical analysis with manual axis marking

## TL;DR

A study found that using image-guided navigation during toric lens implantation improves astigmatism correction accuracy compared to manual methods.

## Contribution

This study demonstrates improved astigmatism correction accuracy using image-guided navigation for toric intraocular lens implantation.

## Key findings

- Image-guided TICL implantation showed significant improvements in surgically induced astigmatism and correction accuracy.
- No intraoperative or postoperative complications were observed in either group.
- Vector analysis metrics like SIA, DV, CI, and AE were significantly better in the image-guided group.

## Abstract

This study compared clinical outcomes of toric intraocular collamer lens (TICL) implantation for myopia and astigmatism correction using image-guided navigation versus manual astigmatic marker alignment, evaluating postoperative astigmatism correction accuracy.

A retrospective analysis included 250 patients (467 eyes) undergoing TICL implantation between January and June 2023. Patients were divided into manual (slit-lamp axis marking) and image-guided (navigation-adjusted lens positioning) groups. Preoperative parameters were comparable. Postoperative visual acuity, refraction, and astigmatism vector analysis (TIA, SIA, DV, CI, AE) were assessed at 3 months.

No significant differences were observed in preoperative parameters, postoperative spherical equivalent (SE), or corrected distance visual acuity (CDVA) (P > 0.05). However, sphere, cylinder, and uncorrected distance visual acuity (UDVA) differed significantly (P < 0.05). Vector analysis revealed no intergroup difference in target-induced astigmatism (TIA) (P > 0.05), but surgically induced astigmatism (SIA), absolute difference vector (DV), correction index (CI), and nd absolute Angle of Error (AE) showed significant improvements in the image-guided group (P < 0.05). Arithmetic AE did not differ between groups (P > 0.05). No intraoperative/postoperative complications (e.g., corneal edema, iris prolapse) occurred.

Image-guided TICL implantation yielded superior visual outcomes and greater astigmatism correction accuracy compared to manual marking, with no complications reported. This highlights the clinical advantage of navigation systems in optimizing refractive precision.