1. Jae Lim Chung MD, MBA 1,3 ; Jin Pyo Hong MD 2,3 ; Kyoung Yul Seo MD, PhD 3 ; Eung Kweon Kim MD, PhD 3 ; Tae-im Kim MD, PhD 3 1 1 Noo Ne Eye Hospital, Seoul, Korea 2 2 Sae Yan Eye Clinic, Seoul, Korea 3 3 Department of Ophthalmology, Yonsei University College of Medicine, Seoul, Korea. None of the authors have any commercial or financial interests

2.  For Successful Outcome Of Toric IOL  Precise Measurement Of Preoperative Corneal Astigmatism  Crucial Point !  To Determine Accuracy & Correlation of 6 Different Keratometers & Topographers 2

3.  Shin-Nippon Co, Ltd, Japan  Measuring capacity Corneal Radius of Curvature ○ 6.50 ~ 9.40 mm Corneal Keratometric Power ○ 36 ~ 52 D Axis Corneal Astigmatism ○ 0 ~ 180° 3

4.  Canon, Japan  Measuring capacity Corneal Radius of Curvature ○ 5.5 ~ 10 mm Corneal Refractive Power ○ 33.75 ~ 61.25 D Axis Corneal Astigmatism ○ 0 ~ 180° 4

5. Carl Zeiss Meditec, Germany 2.5 mm measurement diameter Cf. Manual keratometers ~ 3 mm 30 data points per measurement 6 spots x 5 samples 5 images automatically captured in 0.5 sec Displayed result is average of 5 captured images 5

6. 6  Bausch & Lomb, USA  Topography-based  Simulated K-readings (=Sim K’s) c Axis  3 & 5 mm zone statistics Average & SD of Mean & Astigmatic Power Steep & Flat Axis

7.  Oculus, Germany  Scheimpflug image-based Topographic analysis of Corneal Astigmatism 7

8.  Tracey Technologies, USA  Dual Acquisition Unit EysSys Corneal Topographer ○ Placido ring-based Wavefront analyzer 8

9.  Study Population Preoperative visit for Cataract Surgery 257 eyes of 141 patients ○ Age : 54.5 ± 20.5 yrs ○ Sex : Male - 54, Female - 87  Manual Keratometric Measurement Duplicated examination by 2 skillful examiners Considered as Standard  Compared with 5 other Keratometers 9

10.  Pearson Correlation analysis Between Manual Keratometery Vs Other Methods 10 Vs. Manual Keratometer Pearson Correlation Coefficient iTrace0.947 ORBscan0.921 AutoKeratometer0.919 IOL master0.857 Pentacam0.847

11.  Pearson Correlation analysis Between Manual Keratometery Vs Other Methods 11 Vs. Manual Keratometer Pearson Correlation Coefficient iTrace0.856 AutoKeratometer0.852 IOL master0.751 ORBscan0.646 Pentacam0.633

12.  Duplicated Manual Keratometric Measurements By 2 Experienced Operators Taken As Standard  iTrace Approximated This Standard The Most  Auto Keratometer, ORB & IOL Master Showed To Be Reasonably Accurate.  Trend For ORB Fail To Read Accurately In Steep Axis 12