Teaching Neuro <i>Image</i> : Isolated intracranial Rosai-Dorfman disease mimicking a meningioma

Abstract

A 56-year-old woman presented with involuntary left arm and leg movements. MRI with gadolinium revealed a heterogeneously enhancing, extra-axial mass at the right frontoparietal convexity, causing mass effect, vasogenic edema, and dural thickening (figure). Intraoperatively the mass was noted to invade nearby cortex, sulci, and the superior sagittal sinus. Meningioma was suspected. Pathology revealed a lymphohistiocytic infiltrate with histiocytes positive …