Intracranial dural empyema.

Intracranial dural empyema is a neurosurgical emergency with potentially devastating complications. The prognosis is adversely affected by delay in diagnosis. Modern imaging techniques, especially contrast enhanced CT and MRI, have improved the speed and accuracy of radiological diagnosis of this condition, with an associated reduction in mortality. Despite this, there may still be a delay in diagnosis, partly owing to the subtlety of early radiological signs, especially on unenhanced CT. We present cases that illustrate some of the radiological manifestations, complications and potential pitfalls in diagnosis.