characteristics of early filtering blebs that predict successful trabeculectomy identified via threedimensional anterior segment optical coherence tomography backgroundaims to identify the crosssectional characteristics of filtering blebs at 2 weeks posttrabeculectomy associated with intraocular pressure iop control at 1year posttrabeculectomymethods ninetynine eyes of 94 patients who had undergone primary trabeculectomy were included in this retrospective consecutive case series study surgical success was defined as an iop 15mm hg and a 20reduction in iop without glaucoma medication or additional glaucoma surgeries at 1year posttrabeculectomy subjects were classified into two groups according to whether surgery was successful or unsuccessful blebs were examined using sweptsource threedimensional anterior segment optical coherence tomography and evaluated for quantitative parameters including maximum height maximum wall thickness and ratio of hyporeflective space of the wall as well as qualitative parameters including multiple parallel hyporeflective layers within the wall striping phenomenon decreased visibility of the sclera underlying the bleb shading phenomenon and cystlike structures of the wallresults seventyseven eyes 778 were assigned to the successful group and 22 222 to the unsuccessful group univariate analysis showed significant differences between the groups regarding maximum bleb height p0044 maximum bleb wall thickness p0017 and the striping phenomenon of the bleb wall p0007 multivariate logistic regression analysis confirmed that the striping phenomenon at 2 weeks posttrabeculectomy was significantly associated with success at 1year posttrabeculectomy or 3405 95 ci 1059 to 10947 p0040conclusion taller blebs with thicker walls that showed the striping phenomenon at 2 weeks posttrabeculectomy appeared to predict good iop control at 1 year posttrabeculectomy