ArticleComparison of dual rotating Scheimpflug–Placido, swept-source optical coherence tomography, and Placido–scanning-slit systemsLee, Yong Woo MD; Choi, Chul Young MD, PhD*; Yoon, Geun Young PhD Author Information From Sungkyunkwan University School of Medicine (Lee, Choi), Kangbuk Samsung Medical Center, Department of Ophthalmology, Seoul, South Korea; the University of Rochester Medical Center School of Medicine (Yoon), Department of Ophthalmology, New York, New York, USA *Corresponding author: Chul Young Choi, MD, PhD, Sungkyunkwan University School of Medicine, Kangbuk Samsung Medical Center, Department of Ophthalmology, Pyoung-Dong, Jongro-Ku, Seoul, 110-746, South Korea. E-mail: [email protected] Submitted February 10, 2014; revised July 28, 2014; accepted August 4, 2014.Figure: No Caption available.First author: Yong Woo Lee, MD Sungkyunkwan University School of Medicine, Kangbuk Samsung Medical Center, Department of Ophthalmology, Seoul, South Korea Journal of Cataract & Refractive Surgery: May 2015 - Volume 41 - Issue 5 - p 1018-1029 doi: 10.1016/j.jcrs.2014.08.040 Buy Metrics Abstract Purpose To compare measurements of corneal indices using dual rotating Scheimpflug–Placido, swept-source optical coherence tomography (OCT), and Placido–scanning-slit systems. Setting Kangbuk Samsung Hospital, Seoul, South Korea. Design Prospective evaluation of diagnostic tests. Methods Corneal topography measurements were performed using dual rotating Scheimpflug–Placido (Galilei G2), swept-source OCT (Casia SS-1000), and Placido–scanning-slit (Orbscan IIz) systems. The intraclass correlation coefficients (ICCs) and Bland-Altman plots were used to evaluate the agreement between measurements. Results Fifty post-refractive surgery eyes and 50 normal eyes were evaluated. The agreement in anterior keratometry and pachymetry between the 3 devices was high in both groups (ICC > 0.9). In both groups, the ICC values for posterior keratometry and eccentricity were high between the dual rotating Scheimpflug–Placido and swept-source OCT systems (ICC > 0.9) but not between the Placido–scanning-slit system and the other 2 systems. The Placido–scanning-slit system yielded much steeper values for posterior keratometry in both groups (P < .05). The ICC values for posterior corneal elevation were lower than 0.9 between all 3 devices. The dual rotating Scheimpflug–Placido and swept-source OCT systems showed relatively higher ICC values than the Placido–scanning-slit system in both groups. Maximum posterior elevations were highest with the Placido–scanning-slit system followed by the swept-source OCT system and then the dual rotating Scheimpflug–Placido system. Conclusions Anterior keratometry obtained using 3 devices showed high degrees of agreement. Posterior keratometry and eccentricity showed greater agreement between the dual rotating Scheimpflug–Placido and swept-source OCT systems than with the Placido–scanning-slit system. The dual rotating Scheimpflug–Placido and swept-source OCT systems were equivalent in detecting the shape of the cornea and could be considered interchangeable. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned. © 2015 by Lippincott Williams & Wilkins, Inc.
