Brain abscess and glioblastoma identified by combined proton magnetic resonance spectroscopy and diffusion-weighted magnetic resonance imaging--two case reports.

The differential diagnosis between brain abscesses and necrotic tumors such as glioblastomas is sometimes difficult to establish by conventional computed tomography and magnetic resonance imaging. Combined proton magnetic resonance spectroscopy (1H-MRS) and diffusion-weighted magnetic resonance imaging (DWI) were used to establish the preoperative diagnosis of brain abscess and glioblastoma. DWI visualized the brain abscess as a homogeneous hyperintense lesion and 1H-MRS revealed the presence of acetate, lactate, and amino acids and the absence of the normal brain components. DWI sometimes shows glioblastoma as a hyperintense lesion, but 1H-MRS reveals markedly increased lactate and decreased N-acetyl-aspartate. Combined DWI and 1H-MRS findings can distinguish brain abscess and glioblastoma.