Intra-observer and inter-observer reliability and reproducibility of slit-lamp-adapted optical coherence tomography for evaluation of anterior chamber depth and central corneal thickness.

BACKGROUND AND
OBJECTIVE: To evaluate the intra-observer and inter-observer reproducibility of anterior chamber depth (ACD) and central corneal thickness (CCT) measurements taken by slit-lamp-adapted optical coherence tomography (SL-OCT) and to evaluate concordance of CCT and ACD values obtained by SL-OCT with gold standard devices. PATIENTS AND METHODS: Three images of each eye were taken by two different operators using SL-OCT. ACD and CCT values obtained by each operator were determined and compared to one another and to ultrasonic pachymetry (CCT) and axial OCT biometry (ACD) values obtained by a third, masked operator. Intra-observer and inter-operator reproducibility was assessed using the intraclass correlation coefficient (ICC).
RESULTS: Forty-one eyes of healthy subjects were enrolled. Mean CCT was 0.556 +/- 0.020, 0.557 +/- 0.019, and 0.532 +/- 0.032 and mean ACD was 3.12 +/- 0.36, 3.13 +/- 0.38, and 3.50 +/- 0.44 for operators 1, 2, and 3, respectively (P < .001, for both CCT and ACD). Intra-operator reproducibility for CCT (ICC of 0.948 to 0.995) and ACD (ICC of 0.972 to 0.987) was excellent.
CONCLUSION: SL-OCT provides highly reproducible measures for both CCT and ACD. SL-OCT yields higher values for CCT compared to ultrasonic pachymetry and lower values for ACD compared to axial OCT biometry. Caution should be taken when extrapolating these data into clinical practice until the differences between SL-OCT, axial OCT biometry, and ultrasonic pachymetry can be further elucidated.