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Novel surgical approach to correct late-hypotony in PreserFlo MicroShunt
Bruno Guerreiro Dias1,2, Rafael Whitfield1,2, Inês Leal1,2
1Department of Ophthalmology, Hospital de Santa Maria-Unidade Local de Saúde de Santa Maria, Lisbon, Portugal.
None:
We report a novel surgical approach for managing late hypotony in PreserFlo MicroShunt blebs. Hypotony is a well-known complication of glaucoma filtering surgery, yet treatment options for late-onset cases remain limited. We describe two cases of uveitic glaucoma presenting with hypotony several months after PreserFlo implantation. Both patients were successfully treated with a bleb-modifying procedure. Under local anaesthesia, several interrupted 10-0 nylon sutures were placed in the bleb region to reduce its size and sectorise it, creating an iatrogenic 'ring of steel' that effectively corrected overfiltration. This technique appears to be a feasible and potentially effective option for managing late hypotony.