Assessment of anterior chamber angle using Visante OCT, slit-lamp OCT, and Pentacam

Purpose. To assess and compare the anterior chamber angle (ACA) by different anterior segment imaging techniques. Methods. Forty healthy eyes of 40 normal subjects were recruited and 3 consecutive measurements of ACA were determined prospectively utilizing Visante optical coherence tomography (OCT), slit-lamp OCT (SL-OCT), and Pentacam. Statistical significance of interdevice differences between measurements was evaluated by Wilcoxon signed rank test and Bland-Altman analysis. The repeatability of 3 consecutive measurements was analyzed by repeated measured analysis of variance. Results. Mean nasal and temporal ACA were detected as 31.2+/-8.7 and 32.1+/-8.5 degrees by Visante OCT; 41.6+/-5.9 and 41.8+/-5.2 degrees by Pentacam; and 42.9+/-10.0 and 43.3+/-10.1 degrees by SLOCT. All devices displayed a high intrasession repeatability (Scheffe multiple comparison, p>0.05). ACA detected by Visante OCT were found significantly different from ACA calculated by Pentacam and SL-OCT (p<0.05). On the other hand, ACA data obtained by Pentacam and SL-OCT were found to be statistically similar (p>0.05). Conclusions. Although noncontact ACA measurements using all modalities were easy to handle and demonstrated good repeatability in healthy participants, the tested devices were not regarded as comparable. Hence, the clinician should take the different modalities into consideration during ACA assessment using various devices. (Eur J Ophthalmol 2010; 20: 531-7)