Anterior-Segment Optical Coherence Tomography for Predicting Postoperative Outcomes After Trabeculectomy

Purpose: To determine whether anterior-segment optical coherence tomography (AS-OCT) can be used to predict post-trabeculectomy bleb outcomes.Materials and methods: We divided 58 eyes of 47 trabeculectomy patients into success or failure groups based on their status at 12months after surgery. We then compared various AS-OCT measurement parameters between the two groups at 1 and 2weeks and 1, 3, 6, and 12months. We also analyzed the early post-trabeculectomy bleb parameters with multiple logistic regression, stepwise multiple regression, and the receiver operating characteristic (ROC) curve, to evaluate the power of these parameters to predict long-term outcomes.Results: Intraocular pressure 3 or more months after trabeculectomy was significantly lower in the success group than the failure group (all: P<0.0016). Cleft volume was significantly higher 6 or more months after trabeculectomy in the success group than the failure group (P=0.0027 and <0.0016). Reflectivity of the bleb wall was significantly higher in the failure group than the success group at 2weeks and all later time points (all: P<0.0016). Reflectivity of the bleb wall at 2weeks after trabeculectomy was a risk factor for failure, with an odds ratio (OR) for failure of 2.48 (95% confidence interval, 1.31-4.68, increasing per 10 AU). The area under the ROC curve for reflectivity of the bleb wall at 2weeks after trabeculectomy was 0.775 when the cutoff value was set at 122.8, with sensitivity, specificity, and OR of 78.3%, 80.0%, and 14.4, respectively. A stepwise multiple regression analysis showed that reflectivity of the bleb wall at 2weeks was an independent factor indicating postoperative bleb survival period (=-0.39, P=0.007).Conclusions: Reflectivity of the bleb wall, measured by AS-OCT, may be an early post-trabeculectomy predictor of bleb outcome.