Fig. 1

Brain imaging results. a: A non-contrast computed tomography (CT) image shows a hypodense lesion in the left cerebellar deep nuclei. b: A fluid-attenuated inversion recovery image shows vasogenic edema within the deep white matter of the left cerebellum, especially affecting the left dentate nucleus (b1). These signal abnormalities are observed in multiple enhancing medullary veins with caput medusa appearance in a gadolinium-enhanced T1-weighted axial image (b2). c: Venous phase of the left vertebral artery digital subtraction angiography in anteroposterior view demonstrates umbrella-shaped collections of dilated medullary veins in the left cerebellum (arrow). d: Asymmetrically reduced glucose metabolism in the affected left cerebellum is revealed in ¹⁸F-fluorodeoxyglucose positron emission tomography. e: A follow-up brain CT scan 1 month later shows resolution of the cerebellar edema