Anterior Ocular Biometry Using 3-Dimensional Optical Coherence Tomography
Presented in part at: Association for Research in Vision and Ophthalmology Annual Meeting, April 2008, Fort Lauderdale, Florida.
Received 22 September 2008; received in revised form 4 November 2008; accepted 5 December 2008.
Purpose
To evaluate anterior ocular biometry by comparing the measurements of central corneal thickness (CCT) and anterior chamber depth (ACD) with 3-dimensional corneal and anterior segment optical coherence tomography (CAS-OCT) and other methods.
Design
Cross-sectional study.
Participants
Forty eyes of 40 normal subjects.
Methods
The CCT was measured by 4 methods (CAS-OCT, Scheimpflug camera, scanning-slit topography, and ultrasonic pachymetry), and the ACD was measured by 3 methods (CAS-OCT, Scheimpflug camera, and scanning-slit topography). The anterior chamber volume (ACV) was calculated with CAS-OCT. Repeatability and reproducibility of CAS-OCT measurements were evaluated.
Main Outcome Measurements
The CCT and ACD were measured and compared between devices. The ACV was calculated with CAS-OCT. Coefficient of variation and intraclass correlation coefficient (ICC) were calculated to evaluate repeatability and reproducibility of CAS-OCT measurements.
Results
The mean CCT was 547.0±39.0, 590.0±39.8, 525.0±45.0, and 545.0±40.3 μm with CAS-OCT, Scheimpflug camera, scanning-slit topography, and ultrasonic pachymetry, respectively. Significant differences were observed among the 4 methods (P<0.0001; 1-way analysis of variance [ANOVA]). The CCT measured with Scheimpflug camera was significantly larger than those measured with the other methods (P<0.0001; Bonferroni multiple comparison), but there was no significant difference among the other 3 methods. The mean ACD was 3.01±0.47, 3.04±0.52, and 2.88±0.50 mm with CAS-OCT, Scheimpflug camera, and scanning-slit topography, respectively. There was no significant difference among the 3 methods (P = 0.678; 1-way ANOVA). A significant linear correlation in CCT and ACD were observed between CAS-OCT and other methods (all P<0.0001). The mean ACV calculated with CAS-OCT was 169.7±23.1 mm3. The coefficient of repeatability and reproducibility of CCT and ACD measurements were <5% and ICCs were >0.98.
Conclusions
The CCT measurements were comparable among CAS-OCT, ultrasonic pachymetry, and scanning-slit topography, but Scheimpflug camera yielded a significantly higher CCT value. There was no significant difference in ACD measurements among CAS-OCT, Scheimpflug camera, and scanning-slit topography. The ACV was noninvasively measured by CAS-OCT.
Financial Disclosure(s)
The authors have no proprietary or commercial interest in any materials discussed in this article.
1Department of Ophthalmology, Institute of Clinical Medicine, University of Tsukuba, Ibaraki, Japan
2Computational Optics and Ophthalmology Group, University of Tsukuba, Ibaraki, Japan
3Computational Optics Group, University of Tsukuba, Ibaraki, Japan
Correspondence: Shinichi Fukuda, MD, Department of Ophthalmology, Institute of Clinical Medicine, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575, Japan
Manuscript no. 2008-1145.
Financial Disclosure(s): The authors have no proprietary or commercial interests in any materials discussed in this article.
Supported in part by research grants KAKENHI 19390439 and 19791256 from the Japan Society for the Promotion of Science, Tokyo, Japan.
ABSTRACT