Imipenem/Cilastatin Versus Imipenem/Cilastatin Plus Lipiodol in Genicular Artery Embolization: Safety and Clinical Success in a Comparative Cohort Study.

PURPOSE: To evaluate whether genicular artery embolization (GAE) performed with imipenem/cilastatin (IPM/CS) followed by Lipiodol (IPM/CS+L) is associated with higher clinical success without increased adverse events compared with IPM/CS alone in patients with symptomatic knee osteoarthritis (OA). MATERIALS AND METHODS: This retrospective cohort study included 77 patients (IPM/CS: n=47; IPM/CS+L: n=30) treated between May 2024 and February 2025. Eligible patients had symptomatic OA (Kellgren-Lawrence grades 1-4) and persistent pain (VAS >50 mm). Primary endpoints were longitudinal changes in VAS and WOMAC scores over a 6-month follow-up; secondary endpoints included adverse events and technical/clinical success. Data were analyzed using generalized estimating equations (GEE) adjusted for baseline characteristics. RESULTS: Both groups achieved significant improvements in pain and physical function at 6 months (p < 0.05), with no significant between-group differences in overall clinical success. A significant agent-by-time interaction was observed at 1 month (p = 0.024), indicating a greater early reduction in VAS scores in the IPM/CS+L group; this effect was not sustained at 3 or 6 months. The median number of embolized arteries was lower in the IPM/CS+L group (2 vs. 3, p = 0.040). No severe adverse events occurred, and mild adverse events, including transient skin discoloration, were comparable between groups. CONCLUSION: GAE performed with either IPM/CS alone or a combined IPM/CS+L regimen is safe and provides significant symptomatic relief for knee OA. While Lipiodol offers technical advantages, it does not confer superior long-term clinical efficacy compared to IPM/CS alone.