Venous Sinus Occlusive disease: Comparing Routine MRI to Diffusion Weighted Images

Introduction & Background: Brain MR findings in cerebral venous thrombosis (CVT) are mass effect, hyperintense parenchymal abnormalities on T2 weighted images, and intraparenchymal hematoma. Unlike conventional MR images, diffusion weighted (DW) MR is sensitive to water diffusion, and thus can differentiate vasogenic from toxic edema. In this study, we sought to characterize parenchymal changes associated with CVT on DW images, and de-termine whether this technique could differentiate resolvable injuries from permanent ones. Patients & Methods: We reviewed patient charts and T2 weighted MR images of 20 patients with CVT complicated by intraparenchymal abnormality. DW and conventional MR images were evaluated for any change in the signal intensity, and the signal intensity of the normal appearing contralateral brain was used for comparison. Results: DW images disclosed 3 lesion types: lesions with a high diffusion that resolved, consistent with vasogenic edema; lesions with a low diffusion that persisted, consistent with cytotoxic edema in patients without seizure activity; and lesions with low diffu-sion that resolved in patients with seizure activity. Conclusion: The DW imaging can help to prospec-tively determine the severity of irreversible brain in-jury, and have clinical implications in patient man-agement.