Predicting Success After Angle Surgery

Angle-based minimally invasive glaucoma surgery (MIGS) has become an increasingly important option for patients with open-angle glaucoma. As these procedures are adopted more widely and often earlier in the disease course, the challenge for clinicians is identifying the patients most likely to benefit from angle surgery. Several clinical features are consistently associated with more favorable outcomes, and can help frame preoperative counseling and guide procedure selection.

By
Si Jia Chen, BS
Arsham Sheybani, MD
September 1, 2026
13 min

Glaucoma Physician

Overview

Angle-based minimally invasive glaucoma surgery (MIGS) shows variable outcomes based on patient characteristics. Identifying clinical clues, such as baseline IOP and medication burden, imaging biomarkers, and genetic factors may enhance patient selection for these procedures.

Background

Angle-based MIGS has gained traction as a treatment for open-angle glaucoma, necessitating a better understanding of which patients will benefit most. The complexity of the conventional outflow pathway, including factors like disease severity and prior treatments, contributes to the variability in patient outcomes. As the adoption of these procedures increases, effective patient selection becomes crucial for optimizing surgical success.

Data Highlights

Current evidence is derived from small case series and observational studies, with larger registry analyses providing insights into outcomes based on factors such as procedure type, baseline characteristics, and whether surgery was performed alone or combined with phacoemulsification.

Key Findings

MYOC-associated juvenile open-angle glaucoma patients showed marked IOP reduction after GATT.
Higher baseline IOP correlates with greater absolute IOP reduction but also a higher risk of reoperation.
Lower preoperative medication burden is associated with a higher likelihood of achieving medication-free success.
Earlier-stage glaucoma is linked to better surgical outcomes compared to moderate-to-severe cases.
Combined phacoemulsification and MIGS procedures yield more favorable outcomes than standalone MIGS.

Clinical Implications

Clinicians should consider baseline IOP, medication burden, and disease stage when counseling patients about MIGS. Understanding these factors can guide procedure selection and set realistic expectations for surgical outcomes based on the evidence presented in the studies.

Conclusion

Identifying the right candidates for angle surgery is essential for maximizing the benefits of MIGS, with several clinical features consistently associated with favorable outcomes as indicated by the studies.