Uveoscleral Outflow Enhancement as a Complementary Bio-intervention after Failed Prior Trabecular Outflow Treatment: 12-Month Outcomes of Allograft-reinforced Cyclodialysis in Open Angle Glaucoma

Background: Eyes with open-angle glaucoma uncontrolled after a trabecular outflow procedure have limited options before progressing to bleb-forming surgery. The uveoscleral pathway is distinct, relatively pressure-independent, and conjunctiva-sparing. We report 12-month outcomes of standalone allograft-reinforced cyclodialysis in eyes with IOP that remained uncontrolled after prior trabecular outflow intervention. Methods: Analysis of a multicentre registry (CREST; NCT05506423 ). Eligible eyes had at least one prior trabecular outflow procedure, no prior bleb-forming surgery, and underwent uveoscleral outflow bio-intervention with at least 12 months of follow-up. IOP reported as mean with 95% CI, medication as mean ± SD. Results: Forty-seven eyes were eligible; 91.5% completed 12 months. Consistent with moderate-to-advanced glaucoma, baseline IOP was 22.5 mmHg (20.1, 24.9) on 3.0 (1.3) IOP-lowering medications, with visual field mean deviation −11.7 dB (8.1). 95.7% were pseudophakic. In the per-protocol efficacy analysis, IOP fell 6.1 mmHg (3.7, 8.6), a 25.0% reduction (15.5%, 34.5%; p < 0.001), with no increase in medication. At 12 months, the Kaplan-Meier estimate of freedom from incisional reoperation was 78.2% (61.8%, 88.2%). There were no vision-threatening, clinically significant adverse events associated with the procedure such as persistent hypotony, maculopathy or other complications. Conclusions: In eyes with inadequately controlled IOP following prior trabecular intervention, standalone allograft-reinforced cyclodialysis was associated with clinically meaningful IOP reduction without an increase in medication burden or permanent vision loss.