Diffusion-Weighted MR Imaging of Subdural and Epidural Empyemas

Materials & Methods We retrospectively reviewed diffusion-weighted images obtained from three patients with subdural empyema and three patients with epidural empyema. The patients included two men and four women ranging in age from 17 to 77 years. Their diagnosis was established surgically in three patients and made on the basis of clinical and imaging findings in another three patients. Diffusion-weighted images were obtained at 1.5 T using echo-planar sequences applying a motion-probing gradient of 1000–1326 sec/mm in the z direction. Apparent diffusion coefficient (ADC) maps were created in three patients.