Purpose: To compare the Pentacam to ultrasound biomicroscopy (UBM) or gonioscopy in detecting eyes with primary angle closure (PAC), including PAC suspect and PAC glaucoma.
Patients and methods: In 72 eyes of 39 Japanese with various anterior chamber angle (ACA) widths, the ACA, anterior chamber depth (ACD), and anterior chamber volume (ACV) were measured using the Pentacam, and the ACA was measured by UBM (ACAUBM). Correlations among these parameters and Shaffer's grade based on gonioscopy in the corresponding quadrant were studied. The efficacy of the Pentacam in screening for PAC and PAC suspect was then analyzed by using receiving operator characteristic (ROC) curves and partition analysis.
Results: Shaffer's classification (grade 0 to 4) significantly correlated with each of the measurements using both screening devices (P<0.001), and most strongly correlated with ACAUBM. ACAUBM was also significantly correlated with each Pentacam parameter in all subjected eyes with angle widths of grades 0 to 4 (P<0.001), but not grade 2 or less (P>0.05). In screening eyes with PAC and PAC suspect with the Pentacam, the area under the ROC curve was largest (0.943) when ACV was used as the reference, and partition analysis showed that those eyes were most effectively partitioned with an ACD of 2.58 mm using the Pentacam, resulting in 100% sensitivity and 87.1% specificity.
Conclusions: The Pentacam has potential for safe, noncontact screening of eyes with PAC and PAC suspect, except for those with plateau iris configurations, based on measurements of the ACV and ACD, but not the ACA.