Surgical Techniques for Bleb Revision: A Contemporary Review of Thematic Frameworks and Practical Guidelines

Tissue-preservinG Techniques (Aim: mAinTAin FilTrATion While TreATinG complicATion)These methods are favored when residual filtration is desirable (for example, in eyes with limited glaucomatous reserve) and when conjunctival tissue is adequate to permit less-disruptive repair. Bleb-sparing Epithelial Exchange Concept and RationaleDesigned to remove devitalized or necrotic surface epithelium while preserving the subepithelial bleb architecture and internal inTroducTion Trabeculectomy remains the gold standard for reduction of intraocular pressure in eyes inadequately controlled on medical therapy, but its long-term success is contingent on a functioning filtering bleb.1,2 A well-functioning bleb is typically low-lying, diffuse, minimally vascularized, and features microcysts in the epithelium.3 Although many blebs remain well-formed and diffuse, a proportion evolve into problematic phenotypes such as avascular cystic blebs prone to leakage, ischemic thin blebs causing hypotony, overhanging blebs producing ocular surface dysesthesia, and necrotic or fistulous blebs at risk of infection.4 Each of these may require surgical revision.[5][6][7] Bleb revision techniques have expanded substantially over the past three decades, shifting from primarily excisional approaches to tissue-preserving and minimally invasive procedures and incorporating biologic scaffolds and biomechanical adjuncts to promote durable repair.4,6,8 This review organizes bleb revision into three thematic groups: tissue-preserving, reconstructive, and adjunctive/innovative methods, while retaining the indications, surgical methodology, clinical outcomes, and relative strengths and limitations of each technique so that clinicians can readily match morphology to management.By understanding the nuances of these approaches and their associated evidence base, clinicians can effectively navigate the challenges posed by bleb-related complications, providing an evidence-based framework to guide contemporary surgical decision-making, ultimately optimizing patient care and preserving vision in individuals with glaucoma.