Clinical evaluation of toric intraocular lens implantation based on iTrace wavefront keratometric astigmatism

Background Currently, there is no standard technique for determining corneal astigmatism. 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. 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. 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. Setting: Single site in China, Shanxi Eye Hospital, Shanxi, China. Design: Prospective case series. Methods The study included 85 eyes of 63 patients undergoing phacoemulsification and toric IOL implantation. The IOL power and cylinders were chosen with the help of the iTrace toric planning program using wavefront keratometric astigmatism. Astigmatic changes were assessed using Alpins vector method over a 3-month follow-up period. Results Preoperative mean corneal topographic astigmatism was 1.91 diopters (D) ± 0.69 (standard deviation). Postoperative mean refractive astigmatism decreased significantly to 0.48 D ± 0.34. Surgical induced astigmatism was 1.73 D ± 0.77 and the mean correction index was 0.89 ± 0.22, showing a slight undercorrection. The proportion of astigmatism ≤0.50 D increased from 0 to 71.8% postoperatively. Conclusions This is the first study on evaluation of clinical outcomes of toric IOL implantation in corneal astigmatism patients using iTrace wavefront keratometric readings. The findings show that use of iTrace built-in toric calculator is safe and effective for planning toric IOL surgery for wavefront keratometric astigmatism. Trial registration Current Controlled Trials ISRCTN94956424, Retrospectively registered (Date of registration: 05 February 2020).

Comparison of IOL Power Calculated by Preoperative Biometry versus Intraoperative Wavefront Aberrometry in Thai Cataract Patients.

Background: As people now are expecting more precise and predictable results from cataract surgery. We need to find agreement between the calculated intraocular lens (IOL) power from using the SRK/T based preoperative biometry and the intraoperative wavefront aberrometry (ORA®) in Thai cataract patients. Methods: Eyes that underwent cataract surgery with monofocal or multifocal IOL implantation were enrolled in this prospective study. All eye biometry was measured preoperatively and the ORA intraoperatively. The SRK/T suggested IOL from the preoperative biometry was chosen in all cases. The suggested power and the estimated refraction (EST) from both devices were collected. Bland Altman analysis was used to find the agreement between them. The predicted EST of implanted IOL from both devices were compared with the one-month postoperative SE. Results: The study comprised 97 eyes (79 patients). Of these, 38 eyes (39.2%) had the same suggested IOL power, 36 eyes (37.1%) were within ±0.5D, 20 eyes (20.6%) were within ±1.0D and 3 eyes were beyond ±1.0D. Bland-Altman analysis found the mean difference between IOL power calculated from both devices was 0.39 with LoA of -0.54 to 1.31. The correlation was 98.50% (95%CI 98%- 99.10%). In the same suggested IOL power group, the median difference of EST by preoperative biometry and ORA compared with one-month postoperative SE were -0.08 (95%CI: -0.08, 1.11), and -0.14 (95%CI: -0.88, 1.2), respectively. Conclusions:The ORA and preoperative biometry results were in concordance with each other. The result of preoperative biometry was more accurate than ORA in this study.

Comparison of IOL Power Calculated by Preoperative Biometry versus Intraoperative Wavefront Aberrometry in Thai Cataract Patients.

Background: To find agreement between the calculated intraocular lens (IOL) power from using the SRK/T based preoperative biometry and the intraoperative wavefront aberrometry (ORA®) in Thai cataract patients, and to compare the accuracy of each method with the postoperative refraction results.Methods: Eyes that underwent cataract surgery with monofocal or multifocal IOL implantation were enrolled in this prospective study. All eye biometry was measured preoperatively and the ORA intraoperatively. The SRK/T suggested IOL from the preoperative biometry was chosen in all cases. The suggested power and the estimated refraction (EST) from both devices were collected. Bland Altman analysis was used to find the agreement between them. The predicted EST of implanted IOL from both devices were compared with the one-month postoperative SE. Results: The study comprised 97 eyes (79 patients). Of these, 38 eyes (39.2%) had the same suggested IOL power, 36 eyes (37.1%) were within ±0.5D, 20 eyes (20.6%) were within ±1.0D and 3 eyes were beyond ±1.0D. Bland-Altman analysis found the mean difference between IOL power calculated from both devices was 0.39 with LoA of -0.54 to 1.31. The correlation was 98.50% (95%CI 98%- 99.10%). In the same suggested IOL power group, the median difference of EST by preoperative biometry and ORA compared with one-month postoperative SE were -0.08 (95%CI: -0.08, 1.11), and -0.14 (95%CI: -0.88, 1.2), respectively. Conclusions:The ORA and preoperative biometry results were in concordance with each other. The result of preoperative biometry was more accurate than ORA in this study. Trial Registration: The thai clinical trial registration number: TCTR20171005001Registration Date: October 3rd, 2017First Enrollment: November 10th, 2017

Comparison of IOL Power Calculated by Preoperative Biometry versus Intraoperative Wavefront Aberrometry in Thai Cataract Patients.

Background: To find agreement between the calculated intraocular lens (IOL) power from using the SRK/T based preoperative biometry and the intraoperative wavefront aberrometry (ORA®) in Thai cataract patients, and to compare the accuracy of each method with the postoperative refraction results.Methods: Eyes that underwent cataract surgery with monofocal or multifocal IOL implantation were enrolled in this prospective study. All eye biometry was measured preoperatively and the ORA intraoperatively. The SRK/T suggested IOL from the preoperative biometry was chosen in all cases. The suggested power and the estimated refraction (EST) from both devices were collected. Bland Altman analysis was used to find the agreement between them. The predicted EST of implanted IOL from both devices were compared with the one-month postoperative SE. Results: The study comprised 97 eyes (79 patients). Of these, 38 eyes (39.2%) had the same suggested IOL power, 36 eyes (37.1%) were within ±0.5D, 20 eyes (20.6%) were within ±1.0D and 3 eyes were beyond ±1.0D. Bland-Altman analysis found the mean difference between IOL power calculated from both devices was 0.39 with LoA of -0.54 to 1.31. The correlation was 98.50% (95%CI 98%- 99.10%). In the same suggested IOL power group, the median difference of EST by preoperative biometry and ORA compared with one-month postoperative SE were -0.08 (95%CI: -0.08, 1.11), and -0.14 (95%CI: -0.88, 1.2), respectively. Conclusions:The ORA and preoperative biometry results were in concordance with each other. The result of preoperative biometry was more accurate than ORA in this study. Trial Registration: The thai clinical trial registration number: TCTR20171005001Registration Date: October 3rd, 2017First Enrollment: November 10th, 2017

Clinical Evaluation of Toric Intraocular Lens Implantation Based on iTrace Wavefront Keratometric Astigmatism

Background: There was no standard technique for measuring corneal astigmatism. 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. 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. This study evaluated visual outcomes, rotational stability after performing toric intraocular lens (IOL) implantation planning based on the wavefront aberrometry of the cornea with iTrace. Setting: Single site in China, Shanxi Eye Hospital, Shanxi, China.Design: Prospective case series.Methods: The study included 85 eyes of 63 patients undergoing phacoemulsification and toric IOL implantation. The IOL power and cylinders were chosen with the help of the iTrace toric planning program using wavefront keratometric astigmatism. Over a 3-month follow-up period, astigmatic changes were assessed using the Alpins vector method. Results: Preoperative mean corneal topographic astigmatism was 1.91 diopters (D) ± 0.69 (standard deviation). Postoperative mean refractive astigmatism decreased significantly to 0.48 D ± 0.34. Surgical induced astigmatism was 1.73 D ± 0.77 and the mean correction index was 0.89 ± 0.22, showing a slight undercorrection. The proportion of astigmatism ≤ 0.50 D increased from 0 to 71.8% postoperatively.Conclusions: This is the first study evaluating the clinical outcomes of using iTrace wavefront keratometric readings to plan a toric IOL implantation. The findings show that the iTrace built-in toric calculator with wavefront keratometric astigmatism for toric IOL planning is safe and effective.Trial registration: Current Controlled Trials ISRCTN94956424, Retrospectively registered (Date of registration: 05 February 2020). http://www.isrctn.com/ISRCTN94956424.

Comparison of IOL Power Calculated by Preoperative Biometry versus Intraoperative Wavefront Aberrometry in Thai Cataract Patients.

Background : To find agreement between the calculated intraocular lens (IOL) power from using the SRK/T based preoperative biometry and the intraoperative wavefront aberrometry (ORA ® ) in Thai cataract patients, and to compare the accuracy of each method with the postoperative refraction results. Methods : Eyes that underwent cataract surgery with monofocal or multifocal IOL implantation were enrolled in this prospective study. All eye biometry was measured preoperatively and the ORA intraoperatively. The SRK/T suggested IOL from the preoperative biometry was chosen in all cases. The suggested power and the estimated refraction (EST) from both devices were collected. Bland Altman analysis was used to find the agreement between them. The predicted EST of implanted IOL from both devices were compared with the one-month postoperative SE. Results : The study comprised 97 eyes (79 patients). Of these, 38 eyes (39.2%) had the same suggested IOL power, 36 eyes (37.1%) were within ±0.5D, 20 eyes (20.6%) were within ±1.0D and 3 eyes were beyond ±1.0D. Bland-Altman analysis found the mean difference between IOL power calculated from both devices was 0.39 with LoA of -0.54 to 1.31. The correlation was 98.50% (95%CI 98%- 99.10%). In the same suggested IOL power group, the median difference of EST by preoperative biometry and ORA compared with one-month postoperative SE were -0.08 (95%CI: -0.08, 1.11), and -0.14 (95%CI: -0.88, 1.2), respectively. Conclusions :The ORA and preoperative biometry results were in concordance with each other. The result of preoperative biometry was more accurate than ORA in this study. Trial Registration: The clinical trial registration number: TCTR20171005001 Registration Date October 3 rd , 2017 First Enrollment November 1 st , 2017

Alport Syndrome and Femtosecond Laser Assisted Cataract Surgery

We report the surgical management of a patient with bilateral anterior lenticonus due to Alport syndrome using femtosecond laser-assisted cataract surgery (FLACS) and the Optiwave Refractive Analysis (ORA) system. A 38-year-old man with Alport syndrome presented to our department with visual loss due to anterior lenticonus in both eyes. Adjustments during bilateral FLACS were performed with the software’s calipers to manually delineate the anterior capsulotomy. Multifocal toric intraocular lenses (IOLs) were selected and placed in the posterior chamber with the aid of intraoperative aberrometry. The intended postoperative positioning parameters for the IOL as well as the planned visual acuity and refraction were achieved. The implementation of FLACS and intraoperative wavefront aberrometry is a safe and useful surgical approach for the management of cataract in challenging cases such as patients with anterior lenticonus due to Alport syndrome.

Clinical Evaluation of Toric Intraocular Lens Implantation Based on iTrace Wavefront Keratometric Astigmatism

Background: There was no standard technique for measuring corneal astigmatism. 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. 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. This study evaluated visual outcomes, rotational stability after performing toric intraocular lens (IOL) implantation planning based on the wavefront aberrometry of the cornea with iTrace. Setting: Single site in China, Shanxi Eye Hospital, Shanxi, China. Design: Prospective case series. Methods ： The study included 85 eyes of 63 patients undergoing phacoemulsification and toric IOL implantation. The IOL power and cylinders were chosen with the help of the iTrace toric planning program using wavefront keratometric astigmatism. Over a 3-month follow-up period, astigmatic changes were assessed using the Alpins vector method. Results ： Preoperative mean corneal topographic astigmatism was 1.91 diopters (D) ± 0.69 (standard deviation). Postoperative mean refractive astigmatism decreased significantly to 0.48 D ± 0.34. Surgical induced astigmatism was 1.73 D ± 0.77 and the mean correction index was 0.89 ± 0.22, showing a slight undercorrection. The proportion of astigmatism ≤ 0.50 D increased from 0 to 71.8% postoperatively. Conclusions ： This is the first study evaluating the clinical outcomes of using iTrace wavefront keratometric readings to plan a toric IOL implantation. The findings show that the iTrace built-in toric calculator with wavefront keratometric astigmatism for toric IOL planning is safe and effective.