MRI depiction of chronic intradural (subdural) hematoma in evolution.

The usual chronic subdural hematoma encountered in the elderly is actually thought to be a chronic intradural hematoma, which has been described clinically and anatomically. However, the evolution of how this chronic hematoma occurs remains enigmatic. We report the first magnetic resonance (MR) depiction of an apparent chronic intradural hematoma in evolution over several months in a 61-year-old man after a minimal head injury. The time delay from injury, subsequent focal pachymeningeal T1-gadolinium enhancement, and apparent splitting of the pachymeninges by proven chronic hematoma should serve as a stimulus for further MR investigations of this interesting process.