Abstract

Purpose: To evaluate the morphology of filtering blebs following trabeculectomy with mitomycin C using Anterior Segment Optical Coherence Tomography (AS-OCT) at 1 month after surgery and at 6 months follow up for bleb function. Materials and Methods: A prospective observational study was designed to include 30 eyes (25 patients) who underwent trabeculectomy with mitomycin-C (MMC) in Mcgann District Teaching Hospital, Shimoga over a period of 1 year. Post-operatively morphology of bleb was examined at 1 month and 6 months using Anterior Segment Optical Coherence Tomography. Bleb wall was assessed for thickness of the bleb wall along with its morphology, hyper- or hypo-reflectivity and whether micro-cysts were present or not. Bleb function was considered to be successful when target pressure for each of the patient was attained post-operatively (for mild glaucoma, target pressure is kept as 15-17 mm Hg, for moderate glaucoma 12-15 mmHg and in severe glaucoma 10-12 mmHg) without any medications. Results: Bleb function was successful in 21 (70%) eyes with mean IOP of 10-15 mmHg. Morphology of bleb on AS-OCT at one month showed uniform bleb wall reflectivity in 8 eyes (26.66%) and multiform wall reflectivity in 22 eyes (73.33%). In eyes showing multiform wall reflectivity, bleb morphology pattern of microcysts with multiple layers was seen in 10 eyes (45.45%), microcysts with subconjunctival separation in 8 eyes (36.36%) and only microcyst pattern in 4 eyes (18.18%). When the bleb features at one month were compared with the bleb function at six months, according to the statistical analysis, blebs with the morphology of multiform wall reflectivity with many microcysts were associated with higher chances of success.Conclusions: AS-OCT can be a predictor to assess long term functioning of filtering blebs. The filtering bleb morphology with multiform reflectivity and multiple cavities with microcysts was associated with a good functioning bleb at late postoperative period.

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