Quantified Values of Anterior Chamber Depth and Angle Measurements Using Ultrasound Biomicroscopy and Topography

ABSTRACT

PURPOSE: To compare the measured values of anterior chamber depth and angle in glaucoma patients using Ultrasound Biomicroscopy (UBM) and Orbscan(TM) IIz Topography. METHODS: We measured the anterior chamber depth and angles of four directions in 26 eyes of 13 primary open angle glaucoma (POAG) patients, 26 eyes of 13 normal tension glaucoma (NTG) patients, and 20 eyes of 10 angle closure glaucoma (ACG) patients, with UBM and Orbscan. RESULTS: The values of anterior chamber depth did not show any difference between UBM and Orbscan. The values for anterior chamber angle in POAG and NTG eyes were not different between UBM and Orbscan, but the values for all anterior chamber angles except the superior angle, measured with UBM were significantly larger than those for ACG measured by Orbscan. CONCLUSIONS: Both UBM and Orbscan showed similar results in the measurement of anterior chamber depth and angle in POAG and NTG patients, but showed different results in the anterior chamber angle for ACG patients. UBM will be more useful in evaluating the anterior chamber angle in ACG patients because it can assess the structures of the anterior chamber angle objectively.