Clinical Ophthalmology (Dec 2020)
Rotation Characteristics of Three Toric Monofocal Intraocular Lenses
Abstract
Brent A Kramer,1 David R Hardten,2 John P Berdahl3 1Department of Ophthalmology, University of North Carolina, Chapel Hill, NC, USA; 2Minnesota Eye Consultants, Minnetonka, MN, USA; 3Vance Thompson Vision, Sioux Falls, SD, USACorrespondence: Brent A KramerDepartment of Ophthalmology, University of North Carolina, 2226 Nelson Hwy, Carolina Crossing Suite 200, Chapel Hill, NC 27517 Tel +1 507 360 8728Fax +1 404 500 0643Email [email protected]: To evaluate the rotational stability of the three monofocal toric intraocular lenses (IOLs) via data from an online toric IOL back-calculator.Methods: A retrospective data review of an online toric IOL back-calculator, which allows users to input preoperative toric planning information, postoperative lens orientation, and subjective refraction. Inputted data were used to determine the optimal orientation of the toric IOL to minimize residual refractive astigmatism. Aggregate data from 3/11/2019 to 3/10/2020 were extracted and validated. Only data with ≥ 0.5D of residual refractive astigmatism were used in the study. Pre-operative intended IOL orientation and post-operative IOL orientation were used to calculate IOL rotation.Results: After validation, 5397 entries were determined to represent patient eyes, of which 3238 represented the three monofocal IOLs evaluated. The rate of rotation for AcrySof, TECNIS, and enVista Toric IOLs was 72.7%, 83.4%, and 83.0%, respectively, and location only significantly impacted TECNIS IOLs. The magnitude of rotation for rotated IOLs was similar for all models and was significantly more for IOLs initially placed in the oblique axis. All IOL models tended to rotate in a counterclockwise direction (53.2%, 73.0%, 69.7%, respectively; p< 0.05), and the tendency was greater for IOLs initially located horizontally.Conclusion: The AcrySof IQ Toric IOL was more rotationally stable than both the TECNIS and enVista Toric IOLs; there was no significant difference in rotational stability of the latter two.Keywords: astigmatism, rotation, AcrySof, TECNIS, enVista