Comparison Between Vertical And Horizontal Implantable Collamer Lens V4c Implantation Positioning And Its Effect Upon Decentration And Visual Outcomes

 This study aims to compare ICL decentration and visual outcomes between vertical and horizontal implantation techniques whilst also identifying other contributing and associated factors.

Eye and ENT Hospital, Fudan University, Shanghai, China

In this retrospective study, 80 eyes of 50 patients who underwent ICL V4c implantation at the Eye and ENT Hospital, Fudan University, Shanghai, China, between May 2024 and August 2024 were included. Patients were randomly assigned into vertical and horizontal orientation ICL implantation groups. All studied patients had comprehensive ophthalmic examinations preformed prior to surgery and 1 month postoperatively. Decentration and Higher-order aberrations (HOAs) were measured pre- and 1 month post-operatively using an OPD-Scan III aberrometer.

The mean total decentration was 0.24 ± 0.11 mm (range: 0.04 to 0.49 mm) in the horizontal group and 0.24 ± 0.10 mm (range: 0.00 to 0.34 mm) in the vertical group, with no significant difference between groups. The central hole position was predominantly temporal in both groups. A significant correlation was found between preoperative angle alpha and total decentration in both horizontal and vertical groups. However, no significant correlation was observed between preoperative angle kappa and decentration.

No significant difference in ICL decentration between vertical and horizontal implantation techniques. ICL decentration was related to the  angle alpha, but not the angle kappa.