Segmentation of blush size guides embolic endpoints in genicular artery embolization

Area of Science:

• Interventional Radiology
• Vascular Imaging
• Osteoarthritis Treatment

Background:

• Genicular artery embolization (GAE) is a treatment for knee osteoarthritis.
• A standardized, quantitative endpoint for GAE is currently lacking.
• The angiographic endpoint 'pruning' has been subjectively defined.

Purpose of the Study:

• To identify a quantitative surrogate parameter for the embolic endpoint in GAE.
• To establish objective criteria for assessing embolization success in GAE procedures.
• To correlate imaging findings with clinical outcomes in patients undergoing GAE.

Main Methods:

• Digital subtraction angiography (DSA) images were fused and converted into color maps.
• Segmentation software was used to measure blush size before and after embolization, calculating the blush reduction ratio (BRR).
• Osteoarthritis severity and clinical outcomes (KOOS) were assessed, and embolized vessel and volume data were recorded.

Main Results:

• Blush size and embolic volume increased with higher osteoarthritis grades.
• A median BRR of 0.81 was achieved, indicating significant reduction in blush size post-embolization.
• All Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales showed significant improvement post-GAE.

Conclusions:

• Segmentation of blush size provides a quantitative assessment of embolic endpoints in GAE across various osteoarthritis severities.
• An 80% blush reduction, termed 'pruning,' serves as a reliable endpoint.
• Objective blush quantification enhances reproducibility and supports personalized embolization strategies in GAE.