MRI: — Meningitis – lack of sulcal suppression / CSF non suppressed on FLAIR and thickened enhancing meninges — Abscess – T2 hypointensity – think / smooth enhancing ring due to hemorrhage + paramagnetic free radicals in macrophages / enhancing ring / restricted diffusion = pus
Complications: communicating hydrocephalus due to obstruction at arachnoid villi -> transependymal flow
Clinical: subdural effusion during treatment of meningitis does not necessarily mean treatment failure