Vertical implantable collamer lens as a novel method to increase rotational stability

Area of Science:

• Ophthalmology
• Refractive Surgery
• Biomedical Engineering

Background:

• Toric implantable collamer lenses (ICL) correct astigmatism and myopia.
• Ensuring rotational stability is crucial for optimal visual outcomes.
• Vertical implantation is a novel approach for toric ICL placement.

Purpose of the Study:

• To compare the rotational stability of vertically implanted toric ICLs versus horizontally implanted toric ICLs.
• To evaluate visual acuity, refractive outcomes, and vaulting in both implantation groups.

Main Methods:

• Retrospective matched comparative study of 646 eyes (323 vertical, 323 horizontal toric ICL groups).
• 1:1 matching based on preoperative astigmatism, spherical equivalent, sulcus-to-sulcus, anterior chamber depth, and ICL size.
• Postoperative measurements included visual acuity, refraction, vaulting, and lens rotation at 3 months.

Main Results:

• No significant differences in visual acuity, refractive error, or astigmatism between groups.
• Vertical implantation showed significantly lower vaulting (P < 0.001).
• Mean lens rotation was significantly less in the vertical group (1.11° vs. 3.02°, P = 0.001), with fewer eyes experiencing ≥10° rotation (2.5% vs. 6.5%, P = 0.014).

Conclusions:

• Vertical toric ICL implantation demonstrates excellent rotational stability and effective visual correction.
• This technique offers a promising alternative to horizontal implantation, with potential benefits of lower vaulting and reduced rotation.
• The procedure is an effective novel method for toric ICL implantation.