Acrylamido Polyvinyl Alcohol Microspheres for Uterine Artery Embolization: 12-month Clinical and MR Imaging Results

Purpose: To report the 12-month clinical and magnetic resonance (MR) imaging results of an ongoing two-center registry involving acrylamido polyvinyl alcohol (PVA) microspheres for uterine artery embolization (UAE) for leiomyomas. Materials and Methods: A total of 69 patients underwent UAE with 500-700-μm, 700-900-μm, and 900-1,200-μm acrylamido PVA microspheres (BeadBlock). Thirty-three patients underwent UAE with a limited embolization (protocol A) and 36 patients underwent UAE with stasis as the angiographic endpoint (protocol B). Primary objectives were clinical efficacy measured by a leiomyoma-specific quality of life (QOL) questionnaire and infarction rate of leiomyomas on early contrast agent-enhanced MR imaging. Secondary objectives were in-hospital complications, patient satisfaction, and frequency of clinical failure. Results: Bilateral embolization was technically successful in 68 of 69 patients. A significant decrease (P < .001) in symptom severity and increase in health-related QOL was observed at 3 and 12 months with no significant differences between embolization protocols. However, contrast agent-enhanced MR imaging showed a significantly lower rate of completely infarcted leiomyomas in protocol A compared with protocol B (P < .05). Early clinical failures in patients treated according to protocol A were caused by incomplete tumor infarction. Minor complications occurred in five of 69 patients. Patient satisfaction was similar between protocols. Conclusions: Acrylamido PVA microspheres are a clinically effective and safe embolic agent for UAE. The use of 500-700-μm spheres and a limited embolization results in an unacceptably high rate of failed tumor infarction. Superior imaging results and fewer repeat interventions can be achieved with use of 700-900-μm spheres and stasis as the angiographic endpoint.