Morphological analysis of functional filtering blebs with anterior segment optical coherence tomography: A short-term prediction for success of trabeculectomy.

Abstract

The aim of the study was to analyze morphological parameters of apparently functional filtering blebs with anterior segment optical coherence tomography at 1month post trabeculectomy and to correlate these parameters with intraocular pressure at 6months of follow-up to predict the short-term success of trabeculectomy. In this cross-sectional, descriptive study, apparently functional blebs were evaluated using anterior segment optical coherence tomography with crossline scans after 1month of trabeculectomy. A total of 55 eyes of 55 cases with mean age 49.29 ± 13.72years were included in the study. On anterior segment optical coherence tomography examination, the mean bleb height and mean bleb wall thickness, subconjunctival fluid space, and scleral flap thickness were 1.45 ± 0.39 mm, 0.63 ± 0.25 mm, 0.64 ± 0.26 mm, and 0.45 ± 0.068 mm, respectively. There was statistically significant negative correlation between intraocular pressure at 1month and bleb height (r = -0.25, p = 0.05). There was statistically significant negative correlation between extent of cavity and intraocular pressure at 6months (r = -0.318, p = 0.018). Bleb height showed significant negative correlation with supra-scleral space (r = -0.31, p = 0.02). Multi reflective bleb walls showed statistically significant increased chances of successful functioning blebs at 6months as compared to uniform wall reflectivity (p = 0.00).Bleb function was successful in 37 (67.3%) and unsuccessful in 18 (32.7%) in short term of 6months of follow-up. Bleb walls with multiform wall reflectivity on anterior segment optical coherence tomography at 1month post trabeculectomy show increased chances of success of functioning filtering bleb at 6months. Bleb wall characteristics on anterior segment optical coherence tomography at 1month can predict the short-term success of blebs at 6months.