Itrace toric lens alignment manual#

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.

Itrace toric lens alignment manual#

It can eliminate the potential systematic errors resulting from varying head positions during the preoperative keratometry measurement and from manual marking.Currently, there is no standard technique for determining corneal astigmatism. The TRP marking method using the iTrace aberrometer is simple and accurate for preoperative marking of toric IOLs. The mean toric IOL misalignment was lesser but without significance in the TRP marking group than in the SHM marking group after 3 postoperative months (2.66° ± 1.42° versus 3.29° ± 1.67° P=0.295). There was no statistically significant difference in BCVA, UDVA, preexisting corneal astigmatism, or residual astigmatism between the groups before or after surgery P>0.05. Fifteen eyes of 15 patients were in the TRP marking group and 15 eyes of 15 patients in the SHM marking group. The follow-up duration was 3 months after cataract surgery. TRP marking involved marking three points randomly in the corneal limbus of the patients and accurately marking the horizontal meridian was not required. All patients were prospectively randomized into the TRP marking group or slit-lamp horizontal meridian (SHM) marking group.

Thirty eyes of 30 patients undergoing cataract surgery with coexisting corneal astigmatism of over 1.0 D were included in this study. Prospective, randomized comparative trial.

Department of Ophthalmology, Guangdong Eye Institute, Guangdong Academy of Medical Sciences, Guangdong Provincial People’s Hospital, Guangzhou, China. To evaluate the clinical outcome of the three-random-point (TRP) marking method for toric intraocular lens (IOL) alignment using the iTrace aberrometer (Tracey Technologies Corp., Houston, TX). Yongyi Niu Department of Ophthalmology, Guangdong Eye Institute, Guangdong Academy of Medical Sciences, Guangdong Provincial People’s Hospital, Guangzhou, China Hongliang Lin Shantou University Medical College, Shantou, China Yongjie Qin Department of Ophthalmology, Guangdong Eye Institute, Guangdong Academy of Medical Sciences, Guangdong Provincial People’s Hospital, Guangzhou, China Cheng Yang Department of Ophthalmology, Guangdong Eye Institute, Guangdong Academy of Medical Sciences, Guangdong Provincial People’s Hospital, Guangzhou, China Yanlei Chen Department of Ophthalmology, Guangdong Eye Institute, Guangdong Academy of Medical Sciences, Guangdong Provincial People’s Hospital, Guangzhou, China Jin Zeng Department of Ophthalmology, Guangdong Eye Institute, Guangdong Academy of Medical Sciences, Guangdong Provincial People’s Hospital, Guangzhou, China Hongyang Zhang Department of Ophthalmology, Guangdong Eye Institute, Guangdong Academy of Medical Sciences, Guangdong Provincial People’s Hospital, Guangzhou, China DOI Journal volume & issue