Assessment of the Anterior Segment Using Slit-Lamp Biomicroscope and Gonioscope

ABSTRACT

PURPOSE: To evaluate the accuracy of the Smith method, van Herick technique, and Shaffer grading system, using a slit-lamp biomicroscope and gonioscope that measure anterior chamber depth (ACD), peripheral chamber depth (PCD), and angle width. METHODS: The anterior chamber of 94 eyes of 53 subjects was evaluated by slit-lamp examination with a gonioscope. An A-scan was carried out on all of the subjects, but ultrasound biomicroscope (UBM) was performed on only 42 of 94 eyes. Slit-lamp biomicroscope-assisted measurements, such as ACD, PCD, and angle width, were compared with those by A-scan and UBM. RESULTS: The correlations among ACD measurements, obtained by the Smith method, and those obtained using A-scan (r=0.673, p<0.001) and UBM (r=0.824, p<0.001) were statistically significant. The mean PCD, measured by van Herick technique, was 14.01+/-15.04 %, and its correlation with that of UBM was statistically significant (r=0.706, p<0.001). In addition, the correlation between the mean angle width, measured by Shaffer grading system and by UBM, was also statistically significant (r=0.853, p<0.001). CONCLUSIONS: Assessments of the anterior segment, using a slit-lamp biomicrosope and a gonioscope, are comparable to those of A-scan and UBM measurements and are, therefore, useful for evaluation of the anterior chamber.