Purpose: The most common cause of failure during the first trimester after trabeculectomy is encapsulated bleb and needling bleb revision is a less invasive method in the management of refractory cases. The purpose of this study is to determine the efficacy and safety of Mitomycin-C (MMC) augmented bleb revision of failed filtration surgery. Methods: This study is a before-af- Purpose: The most common cause of failure during the first trimester after trabeculectomy is encapsulated bleb and needling bleb revision is a less invasive method in the management of refractory cases. The purpose of this study is to determine the efficacy and safety of Mitomycin-C ( MMC) augmented bleb revision of failed filtration surgery. Methods: This study is a before-af-