Clinical Outcomes of Ripcord Removal Following A-Stream Glaucoma Shunt Implantation

Purpose: To evaluate the clinical outcomes of ripcord removal following A-stream glaucoma shunt (A-stream; MICROT Inc., Seoul, Korea) implantation. Methods: This retrospective study included 117 eyes that underwent A-stream implantation. The intraocular pressure (IOP)-lowering efficacy, safety of ripcord removal, and associated clinical factors were evaluated. Eyes undergoing removal were stratified by postoperative timing and pre-removal IOP levels. Results: Ripcord removal was performed in 94 eyes (80.3%) at a mean of 67.8 ± 58.9 days. Eyes requiring removal had a significantly higher IOP at one month postoperatively than those that did not (13.7 ± 6.0 vs. 9.8 ± 4.8 mmHg; p=0.004). Following removal, the mean IOP decreased from 18.6 ± 6.7 to 11.6 ± 5.1 mmHg at one week, representing a 36.6% reduction (p<0.05), which remained significant through six months. A greater IOP reduction was associated with higher pre-removal IOP (p<0.05). There was high agreement (80.9%) between the 30-minute and 1-week post-removal IOP responses. The hypotony (IOP < 6 mmHg) rate at one week was 9.6% and was not associated with the removal interval or IOP level. Most cases of hypotony resolved spontaneously, except for one eye (1.1%) with uveitic glaucoma that required ripcord rethreading due to hypotony maculopathy. Conclusion: Ripcord removal in A-stream surgery provides significant additional IOP reduction, particularly in eyes with higher pre-removal IOP, while maintaining a favorable safety profile even with early intervention. A proactive, individualized approach to ripcord removal is recommended to optimize surgical outcomes.