84 - Intra-Operative Factors Associated with Clinical Non-Response to Prostate Artery Embolization

Purpose: Prostate artery embolization (PAE) is an established minimally invasive treatment for lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia. Despite high overall success rates, a subset of patients fails to achieve meaningful symptom improvement. We evaluated intra-operative technical factors among clinical non-responders to identify features that may contribute to treatment failure.

Materials and Methods: From a cohort of 103 PAE patients, 27 (26%) were identified as clinical non-responders, defined by < 5-point reduction in International Prostate Symptom Score at follow-up. Intra-operative records were retrospectively reviewed for embolization laterality, iliac artery tortuosity, origin of the prostatic artery, embolic penetration grade (1–3), number of prostatic arterial feeders, and presence of collateral supply. Descriptive statistics were performed, with exploratory correlations between these factors and angiographic penetration grade.

Results: Bilateral embolization was achieved in 100% of non-responders. Iliac tortuosity was mild in 30%, moderate in 44%, and severe in 26%. Prostatic artery origin was heterogeneous with 35% arising from a common trunk with the superior vesical artery (Type 1) and 28% from the internal pudendal artery (Type 4). Embolic penetration was predominantly Grade 2 (44%) or Grade 3 (44%), though 11% demonstrated only proximal penetration (Grade 1). The mean number of feeders was 2.4 ± 0.6, with collateral supply identified in approximately one-third of cases. Exploratory analyses revealed no statistically significant correlations between tortuosity, vessel number, collaterals, or laterality and embolic penetration grade (all p >0.2).

Conclusion: Clinical non-response to PAE occurred despite technical success in most cases. Complex vascular anatomy including multiple feeders, variant origins, and collaterals was frequently encountered. These patterns highlight technical challenges that may limit procedural efficacy and underscore the need for larger prospective studies.