Diffusion-Weighted MR Imaging of Rim-Enhancing Brain Masses

Abstract
OBJECTIVE. This retrospective study investigated the specificity of restricted water diffusion for the diagnosis of brain abscess. Two of five rim-enhancing brain masses with restricted water diffusion (apparent diffusion coefficient of 0.79 [10-3 mm2/sec] or less) were brain abscesses, but diagnoses in the other cases were metastatic squamous cell carcinoma (two cases) and radiation necrosis. CONCLUSION. Although an important diagnostic sign, restricted water diffusion is not specific for brain abscess.