Road to Genicular Artery Embolization: Importance of the Anastomotic Network

To explore feasibility, safety, perfusion changes and clinical outcomes following retrograde genicular artery embolization (R-GAE).

This prospective exploratory study assessed the technical approach, perfusion changes and clinical outcomes after R-GAE. Anastomoses between genicular arteries (GA) were evaluated during angiography. Technical success was defined as retrograde opacification of GA via anastomoses up to their origin, followed by embolization. Remaining GA were embolized antegrade (A-GAE), and additional A-GAE was performed after R-GAE (A-/R-GAE) if feasible. Time-density curves calculated peak intensity (PI), time-to-arrival (TTA), and area under the curve (AUC). Clinical outcomes were assessed using the knee injury and osteoarthritis outcome score (KOOS) at 6 weeks, 3 and 6 months. No comparison between R-GAE and A-GAE was performed.

A total of 132 vessels were embolized in 35 patients: 73 A-GAE, 39 R-GAE, and 20 A-/R-GAE. Technical success was achieved in all patients, with six cases of mild, transient skin discoloration. All KOOS subscales showed significant improvement at all time points (p < 0.05). No significant changes in PI, TTA, or AUC were observed in the parent vessels or anastomoses after GAE. Target vessels demonstrated reduced AUC (542.6 vs. 253.1; p < 0.01) and PI (110.3 vs. 51.2; p < 0.01), with increased TTA (7.1 s vs. 11.2 s; p < 0.01). Antegrade angiography after R-GAE revealed residual blush in all patients, requiring additional A-GAE.

R-GAE is a safe and feasible catheterization route with potential efficacy at early follow-up. Perfusion areas reached by R-GAE may differ from A-GAE highlighting the anastomotic network's impact on hemodynamics during GAE.