Rotational Stability and Outcomes of V4c Toric Implantable Collamer Lenses Placed at Different Lens Orientations
Purpose:
To evaluate the 12-month rotational stability and outcomes of V4c toric Implantable Collamer Lenses (TICLs) (STAAR Surgical) located at two different lens orientations (horizontal or oblique).
Methods:
This retrospective study included a total of 403 eyes with TICL implantation, enrolled between January 2021 and December 2022, that were divided into two groups based on the minimum intended angle off the horizontal axis: horizontal with 263 eyes at an angle ±22.5 degrees or less and oblique with 140 eyes at a minimum intended angle of greater than ±22.5 degrees. A comparison was made of the preoperative characteristics, surgical outcomes, secondary surgical interventions, footplate positions, and adverse events at 1, 6, and 12 months postoperatively. The rotation-related factors were analyzed.
Results:
At 12 months, there were 243 eyes (92%) in the horizontal group and 130 eyes (93%) in the oblique group that were within ±0.50 diopters (D) of emmetropia. Their rotation proportion was 5.3 % and 5.7%, respectively, and their rotation angle was 9.11 ± 2.84 and 9.96 ± 2.42 degrees, respectively (P = .086). TICL footplates were mostly positioned on the ciliary body. No correlation was observed of lens placement axis, vault, or manifest refraction with rotation in both groups (P > .05). During the follow-up, no vision-threatening complications were observed in both groups. Rotation cases were successfully addressed via alignment or lens exchange.
Conclusions:
TICLs, when implanted across a range of lens orientations, demonstrated favorable rotational stability and postoperative outcomes. The postoperative rotational stability is independent of the placement angle of the TICL. [.
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