A 56-year-old man with oral and genital ulcers and folliculitis presented with distally dominant moderate weakness and impaired sensation with painful paresthesia in the right upper extremity. He presented with spastic paresis of the left lower extremity with Babinski sign. Tendon reflex was absent in the right upper extremity. Cerebrospinal fluid analysis showed mild mononuclear pleocytosis. MRI showed a solitary ring-enhanced lesion in the right pontine base with a high-intensity signal on

more »

... fusion-weighted image (DWI), and a decreased apparent diffusion coefficient (ADC) map (Picture A: Gd+T1WI, B: FLAIR, C: DWI, D: ADC map). Restricted diffusion indicated neuro-Behcet's disease (NBD) or abscess rather than metastatic tumor and glioma that commonly show unrestricted diffusion (1, 2). MRI also revealed compression of the right brachial plexus by an aneurysm of the right subclavian artery. The pontine lesion markedly improved 3 months after initiation of steroid therapy (Picture E: Gd+T1WI, F: FLAIR). A diagnosis of NBD was made on the basis of mucocutaneous and vascular manifestation and his response to steroid therapy, although