A comparison of diagnostic techniques in angle-closure glaucoma.

We evaluated four diagnostic techniques for angle-closure glaucoma (Koeppe gonioscopy, Goldmann three-mirror gonioscopy, compressive Zeiss four-mirror gonioscopy, and the operative chamber deepening procedure) to ascertain their relative effectiveness in determining: (1) whether the angle was open or closed, and (2) whether the closure was appositional or synechial and permanent. Koeppe gonioscopy was the most reliable way to determine whether the angle was open or closed, because this lens caused no artifactual widening of the peripheral angle and allowed the best view over an often convex iris. Zeiss four-mirror compressive gonioscopy or the operative chamber deepening procedure were equally reliable ways to determine whether the closure was appositional or synechial and permanent. A comparison between compressive Zeiss four-mirror gonioscopy and the operative chamber deepening procedure revealed that the latter has therapeutic value as well as diagnostic value, that is, it can separate recently formed adhesions.