Open AccessSimplifying and understanding various topographic indices for keratoconus using Scheimpflug based topographers
Author(s) -
Kumar Doctor,
Krishna Poojita Vunnava,
Rushad Shroff,
Luci Kaweri,
Vaitheeswaran Ganesan Lalgudi,
Krati Gupta,
Gairik Kundu
Publication year - 2020
Publication title -
indian journal of ophthalmology/indian journal of ophthalmology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.542
H-Index - 51
eISSN - 1998-3689
pISSN - 0301-4738
DOI - 10.4103/ijo.ijo_2111_20
Subject(s) - scheimpflug principle , keratoconus , optometry , medicine , ophthalmology , comparability , repeatability , corneal topography , cornea , medical physics , mathematics , statistics , combinatorics
Keratoconus (KC) is a progressive ectatic corneal disorder. There are multiple topographic devices and their varied indices used for diagnosis, detecting progression, and deciding management. It is important to understand the repeatablility, intra- test variabililty, and comparability amongst various topographic devices. The Scheimpflug camera-based devices, such as the Pentacam (Oculus, Wetzlar, Germany), Galilei (Ziemer, Biel, Switzerland), and Sirius (Costruzione Strumenti Oftalmici, Florence, Italy) are known to assist in the detection of early keratoconus and subclinical keratoconus. This article reviews the various Scheimpflug camera-based devices in depth, addressing their different indices, diagnostic accuracy, repeatability, and agreement and identifying the strongest parameter of each device. It will guide the practicing clinician by giving practical tips for decision making in the diagnosis and management of keratoconus.