Multiparametric analysis using MRI after preoperative embolization in meningioma: a preliminary study.

Quantitative evaluation of early perfusion and diffusion changes in meningiomas, including both intratumoral region and peritumoral edema, remains limited within the first 1-2 days postembolization. This study aimed to use multiparametric magnetic resonance imaging (MRI) to investigate early structural and perfusion-related changes in both the intratumoral region and peritumoral edema after preoperative embolization of supratentorial meningiomas. Seven patients with supratentorial meningiomas underwent MRI before and 1-2 days after embolization with Embosphere microspheres (100-300 μm and 300-500 μm), primarily via the middle meningeal artery. Quantitative assessments included intratumoral region and peritumoral edema volumes, quantitative T2, and intravoxel incoherent motion (IVIM) parameters (D, f, D*, fD*, and ΔD). In the intratumoral region, significant reductions in volume (mean change of 28.1%, P = 0.028), quantitative T2 (mean change of 7.4%, P = 0.028), and all perfusion-related IVIM parameters (f, D*, fD*) (P ≤ 0.043) were observed. These findings are consistent with early postembolization ischemia. In contrast, the true diffusion coefficient (D) and the dynamic parameter (ΔD) showed no significant change (P > 0.05). Peritumoral edema showed no significant differences across the measured parameters (P > 0.05). Preoperative embolization is associated with early reductions in viable tumor volume, perfusion-related IVIM parameters, and T2, reflecting imaging changes consistent with early ischemia primarily within the intratumoral region. The stability of peritumoral edema parameters suggests that early postembolization effects are mainly limited to the intratumoral region.