Usefulness of Dual-Energy CT for Differentiating Hemorrhage From Iodine Extravasation in Meningiomas After Preoperative Embolization.

Objective: Discriminating between hemorrhage and iodine extravasation can pose challenges in conventional computed tomography (CCT) images following preoperative embolization for meningioma. This study aimed to assess the efficacy of dual-energy computed tomography (DECT) in differentiating hemorrhage from iodine extravasation after preoperative embolization for meningioma.

Methods: Twenty-one consecutive meningioma patients who underwent CCT before and DECT immediately after preoperative embolization were included in this study. Two independent observers conducted qualitative assessments on CCT and virtual noncontrast (VNC) images and iodine maps (IMs) to differentiate between hemorrhage and iodine extravasation. One observer recorded CT values of hemorrhage and iodine extravasation on CCT and VNC images. The ratio of maximum attenuation to minimum attenuation on VNC images was defined as the VNC ratio. Statistical analysis included Kappa ( κ ) statistics, unpaired t tests, and receiver operating characteristic (ROC) analysis.

Results: Interobserver agreement for qualitative assessment was fair ( κ  = 0.231) for CCT alone and good ( κ  = 0.723) for CCT plus VNC imaging and IM. The addition of VNC imaging and IM to CCT improved differential confidence in 16 (76%) and 18 (86%) cases of the two observers, respectively, increasing the area under the receiver operating characteristic curve (AUROC) from 0.868 to 0.895 and 0.658 to 0.947, respectively. At a cutoff value of 1.527, the VNC ratio was significantly higher for hemorrhage than iodine extravasation ( P  < 0.05), with the highest diagnostic performance (AUROC, 1).

Conclusions: DECT with VNC imaging and IM is useful for differentiating hemorrhage from iodine extravasation in meningiomas with preoperative embolization.