Comparison of Ultrasound Biomicroscopic Changes After Glaucoma Triple Procedure and Trabeculectomy in Eyes With Primary Angle Closure Glaucoma

PURPOSE: To evaluate ultrasound biomicroscopy changes in the anterior chamber angle (ACA) configuration after glaucoma triple procedure (GTP), compared with those seen after trabeculectomy, in eyes with primary angle closure glaucoma (PACG). METHODS: Twenty-nine PACG eyes that underwent GTP were compared with 27 eyes that underwent trabeculectomy only, using ultrasound biomicroscopy. Anterior segment parameters such as anterior chamber depth, angle opening distance (AOD500), trabecular ciliary process distance, trabecular iris angle, iris ciliary process distance, iris thickness along the trabecular ciliary process distance line (ID1), scleral ciliary process angle, scleral iris angle, and angle recess area were measured preoperatively and at 3 months postoperatively; these parameters were then compared between the procedures. RESULTS: Among the anterior segment parameters, postoperative increases in the anterior chamber depth, AOD500, and angle recess area were statistically significant in the eyes that underwent trabeculectomy. For the eyes that underwent GTP, all parameters except the iris ciliary process distance and ID1 were significantly increased after the operation. CONCLUSIONS: For the eyes that underwent GTP, the ciliary body process was posteriorly positioned and the ACA was significantly increased after the operation, as compared with the eyes that underwent trabeculectomy. The posterior shift of the ciliary process only after GTP was indirect evidence that the lens plays an important role in ACA configuration in eyes with PACG.