Influence of Implantation Technique on Rotational Stability of a Frosted-Haptic Toric Intraocular Lens: A Prospective Contralateral-Eye Study

Influence of Implantation Technique on Rotational Stability of a Frosted-Haptic Toric Intraocular Lens: A Prospective Contralateral-Eye Study

This prospective, randomized contralateral-eye study evaluates whether the implantation technique influences the rotational stability and refractive outcomes of the TECNIS Eyhance™ Toric II intraocular lens (IOL) during cataract surgery. Although balanced salt solution (BSS) hydroimplantation has been proposed to reduce postoperative IOL rotation by eliminating retained ophthalmic viscosurgical device (OVD), the effect of implantation technique on the rotational stability of modern frosted-haptic toric IOLs remains uncertain.

Patients undergoing bilateral cataract surgery with regular corneal astigmatism receive TECNIS Eyhance™ Toric II IOLs in both eyes. One eye is randomized to OVD-assisted implantation and the fellow eye to BSS-assisted hydroimplantation. The primary outcome is postoperative rotational stability assessed using OPD-Scan III at postoperative day 1, week 1, and month 1. Secondary outcomes include postoperative refractive astigmatism, astigmatic prediction error, and visual acuity. The study aims to determine whether implantation technique influences postoperative rotational stability or refractive performance when using a contemporary frosted-haptic toric IOL.

Inclusion Criteria:

• Adults with senile cataract requiring bilateral cataract surgery.
• Regular corneal astigmatism of ≥1.00 diopter.
• Axial length between 22.0 mm and 25.0 mm.
• Eligible for implantation with the TECNIS Eyhance™ Toric II intraocular lens.
• Able and willing to provide written informed consent.

Exclusion Criteria:

• Inconsistent corneal astigmatism measurements (difference >0.20 D in magnitude or >5° in axis among the four diagnostic devices).
• Visually significant dry eye disease with positive corneal fluorescein staining.

Irregular corneal astigmatism or corneal opacity.

• Ocular comorbidities that could affect toric IOL stability or visual outcomes (e.g., pseudoexfoliation syndrome, advanced glaucoma, or macular pathology).
• Intraoperative complications or generalized zonular weakness requiring implantation of a capsular tension ring.
• Significant postoperative day 1 corneal edema precluding reliable rotational measurements.
• Inability to comply with the follow-up schedule.