Optical coherence tomography and ultrasound biomicroscopy imaging of opaque corneas

PURPOSE:: The purpose was to determine the interchangeability of ultrasound biomicroscopy (UBM) and anterior segment optical coherence tomography (AS-OCT) for corneal opacity depth measurement. METHODS:: Twenty-six eyes of 26 consecutive patients with corneal opacities were examined by both AS-OCT and UBM. The corneal thickness and the corneal opacity depth were measured and compared. The interchangeability was determined by Bland-Altman plotting. RESULTS:: The difference in the full corneal thickness and in the corneal opacity depth between OCT and UBM was 5 ± 7 μm and-1 ± 8 μm, respectively. There were strong correlations and no significant differences between the paired parameters (all r > 0.99, P < 0.01). The limits of agreement were 5 ± 14 μm for the corneal thickness and-1 ± 14.8 μm for the corneal opacity depth. CONCLUSIONS:: AS-OCT and UBM may be used interchangeably for measuring both full corneal thickness and corneal opacity depth in patients with corneal opacity.