Presentation
Signs of raised intracranial pressure.
Patient Data
Large well-circumscribed extra-axial mass of retroclival prepontine location extending to the foramen magnum. It displays an isosignal to the cortical grey matter on both T1 and T2, slightly high signal on FLAIR with a vivid heterogeneous enhancement on postcontrast sequences. No calcification or hemorrhagic component seen on the GE sequence. It shows a similar signal intensity to the brain on DWI and ADC. It compresses and displaces the brainstem and 4th ventricle as well as the vertebral and basilar arteries with tonsillar herniation. Dilated 3rd and lateral ventricles with transependymal edema in keeping with obstructive hydrocephalus.
Case Discussion
MRI features of a large retroclival prepontine vividly enhancing extra-axial mass most consistent with meningioma.