Clinical ScienceLong-term Chronological Changes in Very Asymmetric KeratoconusKoh, Shizuka MD, PhD*,†; Inoue, Ryota MS*,‡; Maeda, Naoyuki MD, PhD†; Kabata, Daijiro MPH§; Shintani, Ayumi MPH, PhD§; Jhanji, Vishal MD¶; Klyce, Stephen D. PhD, FARVO‖; Maruyama, Kazuichi MD, PhD*,†; Nishida, Kohji MD, PhD†Author Information *Department of Innovative Visual Science, Osaka University Graduate School of Medicine, Osaka, Japan; †Department of Ophthalmology, Osaka University Graduate School of Medicine, Osaka, Japan; ‡Seed Cooperation, Tokyo, Japan; §Department of Medical Statistics, Osaka City University Graduate School of Medicine, Osaka, Japan; ¶Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA; and ‖Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York, NY. Correspondence: Shizuka Koh, MD, PhD, Department of Innovative Visual Science, Osaka University Graduate School of Medicine, Room E7, 2-2 Yamadaoka, Suita Osaka 565-0871, Japan (e-mail: [email protected]). S. Koh and N. Maeda received fees from Oculus for a sponsored seminar, not related to this article. R. Inoue is an employee of Seed Co. The remaining authors have no funding or conflicts of interest to disclose. Cornea: May 2019 - Volume 38 - Issue 5 - p 605-611 doi: 10.1097/ICO.0000000000001890 Buy Metrics Abstract Purpose: To investigate chronological changes in patients with very asymmetric keratoconus (KC) by Scheimpflug-based corneal tomographic evaluation. Methods: We retrospectively reviewed the clinical records of 382 patients with KC attending a university hospital. Patients who were diagnosed with KC in one eye and forme fruste keratoconus in the other eye at the last visit and followed up with Scheimpflug-based tomographic corneal imaging were included. The anterior radius of curvature (ARC) and posterior radius of curvature (PRC) obtained at a 3.0-mm optical zone and the thinnest pachymetry reading of corneal thickness (Tmin), were used to investigate the chronological changes in tomographic parameters. Results: Twenty-six patients aged 16 to 66 years met the inclusion criteria. The mean observation period was 6 years and 4 months. There was a significant increase in annual change in PRC with a longer follow-up period after initial examination (P = 0.011). Moreover, a greater increase in annual change in ARC was observed in patients in whom the initial examination was performed at a younger age than in those in whom it was performed at an older age (P < 0.001). Conclusions: On the basis of tomographic evaluation, even if the measured values are almost stable and within normal limits, a long-term clinical follow-up is warranted in forme fruste keratoconus eyes. Younger patients with very asymmetric keratoconus should be monitored carefully. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.