Goniometry with optical coherence tomography in angle-closure glaucoma

Purpose. Visualization of the anterior chamber angle is an important diagnostic method in patients with angle-closure glaucoma. In this study, optical coherence tomography (OCT) was used to image the angle width, the iris configuration, and the iris thickness in patients with angle-closure glaucoma. Methods. Thirteen eyes of 11 patients suffering from angle-closure glaucoma were studied with slitlamp-adapted OCT. All patients were treated with Nd:YAG laser iridotomy. The angle width (degrees), the angle opening distance (ADD) (mu m), and the iris thickness (pm) were measured with OCT. The configuration of the iris was classified as steeply convex, convex, or flat. Results. The mean angle width was preoperatively 5.1 +/- 5.0 degrees (0-15 degrees) and enlarged significantly (p=0.007) to 10.4 +/- 5.5 degrees (0-19 degrees) postoperatively. The AOD changed from 71 +/- 55 mu m (0-157 mu m) preoperatively to 143 +/- 74 mu m (0-256 mu m) postoperatively (p < 0.001). The mean iris thickness was 338 +/- 33 mu m. With the exception of two eyes the predominant iris configuration changed from convex to flat. Conclusions. OCT allowed visualization and noninvasive assessment of the anterior chamber angle region in patients with angle-closure glaucoma. Our results suggest that goniometry with OCT could improve the evaluation in patients with narrow or closed anterior chamber angles.