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Does Dry Eye Affect Repeatability of Corneal Topography Measurements?
Aysun Şanal Doğan1, Canan Gürdal1, Mehmet Talay Köylü1
1University of Health Sciences, Dışkapı Yıldırım Beyazıt Training and Research Hospital, Ophthalmology Clinic, Ankara, Turkey.
Objectives:
The purpose of this study was to assess the repeatability of corneal topography measurements in dry eye patients and healthy controls.
Materials And Methods:
Participants underwent consecutive corneal topography measurements (Sirius; Costruzione Strumenti Oftalmici, Florence, Italy). Two images with acquisition quality higher than 90% were accepted. The following parameters were evaluated: minimum and central corneal thickness, aqueous depth, apex curvature, anterior chamber volume, horizontal anterior chamber diameter, iridocorneal angle, cornea volume, and average simulated keratometry. Repeatability was assessed by calculating intra-class correlation coefficient.
Results:
Thirty-three patients with dry eye syndrome and 40 healthy controls were enrolled to the study. The groups were similar in terms of age (39 [18-65] vs. 30.5 [18-65] years, p=0.198) and gender (M/F: 4/29 vs. 8/32, p=0.366). Intra-class correlation coefficients among all topography parameters within both groups showed excellent repeatability (>0.90).
Conclusion:
The anterior segment measurements provided by the Sirius corneal topography system were highly repeatable for dry eye patients and are sufficiently reliable for clinical practice and research.
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