2026 Poster Presentations
P157: IMPACT OF POLYVINYL ALCOHOL PARTICLE SIZE ON OUTCOMES OF PREOPERATIVE EMBOLIZATION FOR SKULL BASE MENINGIOMAS
Rommi Kashlan, BS; Hithardhi Duggireddy, MS; Thomas McCaffery, BS; J. Manuel Revuelta-Barbero, MD, PHD; Karen Salmeron-Moreno, MD; Karthik Papisetty, BA; Gustavo Pradilla, MD; Tomas Garzon-Muvdi, MD, MSc; Emory University
Background: Preoperative embolization is often employed in the management of skull base meningiomas to reduce intraoperative blood loss and facilitate safe tumor resection. Polyvinyl alcohol (PVA) particles are widely used embolic agents, yet the influence of particle size on surgical outcomes remains poorly defined. Smaller particles may allow deeper intratumoral penetration and more complete angiographic devascularization, whereas larger particles may provide safer occlusion of proximal feeders with less risk of ischemic complications. Clarifying the clinical impact of PVA particle size could help optimize embolization strategies for these complex tumors.
Methods: We performed a retrospective analysis of patients with skull base meningiomas who underwent preoperative embolization with PVA particles. Patients were stratified into two cohorts based on embolic particle size: small (150–250 μm) and large (250–355 μm). Demographics, tumor volume, procedural parameters, and clinical outcomes were assessed. Primary endpoints included perioperative complications, angiographic blush reduction, percent blood supply embolized, procedure duration, ICU stay, and modified Rankin Scale (mRS) scores at discharge. Secondary endpoints included discharge disposition and change in functional status from pre-embolization baseline.
Results: Thirty patients were included in the study. Large-particle embolization accounted for 53.3% of cases, small-particle embolization for 33.3%, and mixed particle size use for 13.3%. Tumor volume at baseline was greater in the large-particle group (mean 285.7 cm³) compared to the small-particle group (mean 253.4 cm³). Pre-embolization mRS scores were similar between groups. At discharge, good functional outcome (mRS ≤2) was observed in 70% of the large-particle cohort compared to 60% of the small-particle cohort. Median ICU stay was slightly shorter in the large-particle group (2 days vs 3 days). Complications occurred in six patients, distributed evenly across groups, with no clear association between particle size and complication rate. Angiographic outcomes demonstrated more frequent significant tumor blush reduction in the small-particle cohort (65% vs 52% with large particles), consistent with greater penetration into tumor vasculature. Despite this, the proportion of tumor blood supply embolized at surgery was comparable between groups, averaging over 90% in both. Operative duration was notably shorter for patients embolized with larger particles (mean 181.5 minutes vs 322.1 minutes with small particles). Functional recovery was similar between cohorts. The mean change in mRS from baseline to discharge showed modest improvement in both groups. Discharge disposition favored acute rehabilitation or home in patients treated with larger particles, whereas those embolized with smaller particles were more often discharged to long-term acute care or skilled nursing facilities.
Conclusion: PVA particle size influences procedural and perioperative dynamics in the embolization of skull base meningiomas but does not appear to substantially affect overall complication rates or short-term functional outcomes. Smaller particles produced greater angiographic devascularization, yet this did not translate into improved functional recovery. Larger particles were associated with shorter operative times and more favorable discharge dispositions despite treating larger tumors. These findings suggest that large PVA particles may provide a safe and efficient balance in preoperative embolization, while the theoretical advantage of deeper penetration with small particles may not confer clinical benefit.
