First row : The wall of the cavity is smooth and high signal intensity inner-space of cavity with edematous lesion around the cavity (first line). Peripheral rim of cavity is enhanced on the Gadoliniumenhanced image (second line). On T1-weighted image (third line), the inner space of the cavity shows low signal intensity. Diffusion weighted image (forth line) reveals a lesion of high signal intensities in the left frontal lobe. Second row : Follow up MRI after 20 days of antibiotics treatment demonstrates abnormal signal intensities in new lesions (second line), and the right trigone periventricular white matter (third line). Apparent diffusion coefficient (ADC) map image shows low signal intensity lesion in the splenium of corpus callosum and right trigone peri-ventricular white matter (forth line). T2 FLAIR image shows slightly high signal intensity lesion in both dentate nuclei of cerebellum (fifth line), and in the splenium of corpus callosum (sixth line). Third row : Four weeks after discontinuation of metronidazole, the radiological resolution of MIEP lesions (third line).