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Updated: Apr 17, 2026
Doppler Optical Coherence Tomography of Retinal Circulation
Published on: September 18, 2012
Intraobserver repeatability and interobserver reproducibility of corneal measurements in normal eyes using an optical
Jinesh M Shah1, Daphne Han1, Hla Myint Htoon1
1From the Department of Ophthalmology (Shah), Changi General Hospital, Singapore National Eye Centre (Han, Mehta), Singapore Eye Research Institute (Han, Htoon, Mehta), the Department of Ophthalmology (Mehta), Yong Loo Lin School of Medicine, National University of Singapore, and the Department of Clinical Sciences (Mehta), Duke-NUS Graduate Medical School, Singapore.
Purpose:
To study intraobserver and interobserver reproducibility of corneal topography and aberrometry measurements using a device combining optical coherence tomography (OCT) and a Placido disk (Visante Omni).
Setting:
Singapore National Eye Centre, Singapore.
Design:
Prospective nonrandomized study.
Method:
Measurements of simulated keratometry (K), anterior mean curvature, spherical anterior and posterior elevations, 4.5 mm diameter zone aberrometry (spherical aberration, asphericity, astigmatism), pachymetry, and white-to-white (WTW) diameter were taken in normal right eyes. Mean biases and limits of agreement (LoA) were obtained using Bland-Altman analysis.
Results:
Regarding intraobserver repeatability, the mean biases for simulated K, anterior mean curvature, spherical anterior/posterior elevation, 4.5 mm zone aberrometry, pachymetry, and WTW diameter were not statistically significant (P > .05). The LoA for the anterior mean curvature measurements were flat K, -3.96 diopters (D) and 4.86 D; steep K, -4.50 D and 4.27 D; mean K, -2.48 D and 2.09 D. The LoA for WTW were -9.90 mm and 8.74 mm. Regarding interobserver reproducibility, the mean biases for simulated K, anterior mean curvature, spherical anterior/posterior elevation, 4.5 mm zone aberrometry, pachymetry, and WTW diameter were not statistically significant (P > .05). The LoA for anterior mean curvature were flat K, -4.05 D and 4.13 D; steep K, -5.08 D and 3.85 D; mean K, -2.65 D and 2.29 D. The LoA for WTW diameter were -8.79 mm and 8.24 mm.
Conclusions:
The OCT-Placido device had high intraobserver and interobserver clinical reproducibility for measurements of simulated K, 4.5 mm zone aberrometry, pachymetry, and standard anterior/posterior corneal elevation. However, intraobserver and interobserver reproducibility of anterior mean curvature measurements and WTW diameter was lower.
Financial Disclosure:
No author has a financial or proprietary interest in any material or method mentioned.
