Contrast-enhanced CT of acute isodense subdural hematoma.

Originally, all acute subdural hematomas were thought to be hyperdense with respect to brain on CT (1 ). But over the last 1 0-15 years, cases of acute isodense subdural and epidural hematomas have been reported [2-6). Although contrast-enhanced CT has aided in the visualization of chronic isodense subdural hematomas [7), the use of contrast material was not efficacious in two of the acute isodense hematoma cases reported (4, 5) , and was not performed in four others [2-4, 6]. This report illustrates the usefulness of contrast-enhanced CT in the evaluation of a case of acute head trauma with unexplained midline shift. In our case, an acute isodense subdural hematoma enhanced, as did the CSF cisterns and the isodense cerebral contusions. The recognition of this constellation of radiologic signs on unenhanced and enhanced CT in the setting of acute head trauma has an important hematologic implication and suggests the underlying presence of disseminated intravascular coagulation (DIC).