Anterior segment features in nanophthalmos with secondary chronic angle closure glaucoma: An ultrasound biomicroscopy study

Abstract

PURPOSE. We compare anterior segment parameters and the risk of malignant glaucoma between nanophthalmos with secondary chronic angle closure glaucoma (NSCACG) and chronic primary angle-closure glaucoma (CPACG). METHODS. This retrospective case-control study included 32 NSCACG (32 eyes) and 36 CPACG (36 eyes) patients. Anterior segment parameters, including anterior chamber depth (ACD) and width (ACW), pupil diameter (PD), lens vault (LV), ciliary process-ciliary process distance (CCD), angle opening distance500 (AOD500), trabecular-iris angle (TIA), trabecular-ciliary processes distance (TCPD), ciliary body max thickness (CBMT), iris convexity (IC), peripheral iris thickness (PIT), iris-zonule distance (IZD), trabecular ciliary process angle (TCPA), and anterior vault (AV), were measured by ultrasound biomicroscopy. A-scan ultrasonography measurements, including lens thickness (LT) and axial length (AL), also were reviewed. RESULTS. ACD, ACW, CCD, TCPD, and AL were smaller, whereas the LV, LT/AL, LV/LT, LV/ACD, LT/ACD, LV/AV, and AV/AL were larger in NSCACG compared to CPACG eyes (all Bonferroni-corrected P < 0.05). Eyes with NSCACG had a higher risk of malignant glaucoma postoperatively than eyes with CPACG (P ¼ 0.018). CONCLUSIONS. Characterized by narrower anterior segment, forward movement of larger lens, more anteriorly rotated ciliary bodies, and smaller CCD, NSCACG eyes have a higher risk of malignant glaucoma than CPACG eyes.