Fig. 1

Brain magnetic resonance imaging of the patient. Postcontrast T1-weighted saggital and axial imaging (a, b) showed enhancement in subarachoid space of cerebellum, typically in the great horizontal fissure. Diffusion-weighted imaging (c) showed high-intensity area in the great horizontal fissure. Susceptibility-weighted imaging (d) showed nonlinear multiple low intensity spots. These multiple spots are not enhanced in axial postcontrast T1-weighted image (b). Follow up MRI on day 42 showed that the multiple low-intensity spots persisted, but were disappearing (e)