Modified superior bleb needling of rare hypertrophic bleb after trabeculectomy: A case series

Background: Hypertrophic bleb is a rare complication of glaucoma filtration surgery characterized by an elevated bleb extended through the nasal 180 degrees of the eye and usually with a normal IOP. Currently, there is little experience and no existing standardized treatment. We describe a new method called modified superior bleb needling and evaluate the clinical outcomes in affected eyes. Methods: In this retrospective, consecutive interventional case series, patients who developed hypertrophic blebs after trabeculectomy from November 2015 to August 2020 at West China Hospital were enrolled. We innovatively adopted a modified superior bleb needling to allow aqueous humor to outflow into the superior subconjunctival space. Repeat needlings were performed if necessary. The technical and clinical success rate and complications were reported. Results: At the time of the last follow-up, complete success was achieved in 8/10 patients, qualified success was achieved in 9/10 patients, and failure was achieved in 1/10 patients. Eight patients had a low filtering bleb and IOP <= 21 mmHg. There was no statistically significant difference between the preneedling and postneedling IOP (p > 0.05). Conclusion: Modified superior bleb needling is effective for hypertrophic blebs after trabeculectomy, and there was no significant impact on anterior chamber depth or IOP, making it a viable or preferred alternative option. It is worthy of further study and wider usage.