![]() Prospectively, 85 consecutive eyes of 63 patients having 2.2-mm coaxial microincision phacoemulsification with monofocal toric IOL (AcrySof Toric) implanted were enrolled between May 2018 and February 2019 at the Shanxi Eye Hospital (Taiyuan, Shanxi, China). After a detailed explanation, informed consent was obtained from each patient prior to enrollment. Institutional review board approval was obtained for the project and this study followed the tenets of the Declaration of Helsinki. To the best of our knowledge, the present study is the first to investigate the outcomes of toric IOL planning with iTrace toric calculator based on wavefront keratometric astigmatism. However, the outcomes of using iTrace toric calculator based on wavefront keratometric (WFK) astigmatism for toric IOL planning must be evaluated. It is supposed to be more accurate than iTrace simulated keratometry which is calculated based on only 4 points on the circle of 3 mm. The iTrace wavefront aberrometry of cornea calculates steep power and axis based on the best Zernike mathematical fit from all topo data within 4 mm circle. The iTrace toric IOL calculator offers a choice to match the keratometric values measured by wavefront aberrometry of the cornea or simulated keratometry. Thus, there is no standard technique for measuring corneal astigmatism.Ī wavefront analysis using an iTrace Surgical Workstation (Tracey Technologies Corp., Houston, TX, USA) integrates an aberrometer, corneal topography, and a toric IOL calculator. Since each device has its own characteristics, measurements obtained from different devices may not be comparable due to different refractive indices or measurement areas being used. Keratometers, corneal topographers, anterior segment tomographers, and intraoperative aberrometers can each provide corneal measurements necessary to accurately predict the ideal IOL cylinder power and alignment meridian to correct astigmatism during cataract surgery. Toric intraocular lenses (IOLs) have become an increasingly common technique due to their advantage of predictably, stably, and safely correcting a preexisting astigmatism. Significant postoperative astigmatism might affect both vision quality and spectacle independence, leading to unsatisfactory outcomes. Corneal astigmatism management has become crucial in modern cataract and refractive surgery practices. Also, 21.3–22.4% of patients with cataracts have 1.0–1.5 D of corneal astigmatism with 10.6–12.4% of patients having 1.5–2.0 D and 8.2–13.0% of patients having 2.0 D or more. Trial registrationĬurrent Controlled Trials ISRCTN94956424, Retrospectively registered (Date of registration: 05 February 2020).Īn estimated 40–50% of the population aged over 60 years has more than 1.0 diopter (D) of keratometric astigmatism. The findings show that use of iTrace built-in toric calculator is safe and effective for planning toric IOL surgery for wavefront keratometric astigmatism. This is the first study on evaluation of clinical outcomes of toric IOL implantation in corneal astigmatism patients using iTrace wavefront keratometric readings. The proportion of astigmatism ≤0.50 D increased from 0 to 71.8% postoperatively. Surgical induced astigmatism was 1.73 D ± 0.77 and the mean correction index was 0.89 ± 0.22, showing a slight undercorrection. Postoperative mean refractive astigmatism decreased significantly to 0.48 D ± 0.34. Preoperative mean corneal topographic astigmatism was 1.91 diopters (D) ± 0.69 (standard deviation). Astigmatic changes were assessed using Alpins vector method over a 3-month follow-up period. The IOL power and cylinders were chosen with the help of the iTrace toric planning program using wavefront keratometric astigmatism. The study included 85 eyes of 63 patients undergoing phacoemulsification and toric IOL implantation. ![]() Setting: Single site in China, Shanxi Eye Hospital, Shanxi, China. This aim of this study was to evaluate visual outcomes and rotational stability after toric intraocular lens (IOL) implantation using the wavefront aberrometry of the cornea with iTrace. It was supposed to be more accurate than iTrace simulated keratometry which was calculated based on only 4 points on the circle of 3 mm. ![]() The iTrace wavefront aberrometry of cornea calculated steep power and axis based on the best Zernike mathematical fit from all topo data within 4 mm circle. ![]() Currently, there is no standard technique for determining corneal astigmatism. ![]()
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