CNS angiitis as a brain tumor mimic with a branching vascular abnormality on T2* MRI.

A 24-year-old woman with slowly progressive altered mental status and fevers was found to have multiple brain mass lesions. A characteristic branching vascular pattern on T2* MRI (figure 1D) was key to identifying these mass lesions as vascular in origin. CSF was inflammatory and serologic testing supported the diagnosis of systemic lupus erythematosus with concomitant CNS angiitis affecting deep medullary and ependymal veins, with resulting inflammation, hemorrhage, and infarct. Symptoms and mass effect/edema improved with steroid treatment and time. CNS angiitis can present as an intracranial mass lesion. The branching venous pattern on T2* MRI (figures 1D and 2D) is key to distinguishing from neoplasm.