[Brain Abscess].

Although the prognosis of brain abscesses has historically improved, the mortality rate still ranges from 5 to 32%, with ventricular perforation reaching 50% and 85-100% in fungal brain abscesses. The characteristic finding of ring-like enhancement by contrast-enhanced imaging is non-specific, and DWI, SWI and MR spectroscopy are very useful in differentiating brain abcesses from necrotizing brain tumors. Brain abscesses show apparent diffusion restriction on the DWI/apparent diffusion coefficient(ADC) map, whereas necrotizing brain tumors often show a weak diffusion restriction. The "dual rim sign" on SWI is also a highly specific finding of brain abscess.