[Clinical features and CT diagnostic criteria for diffuse axonal brain injury]

The clinical and computed tomographic features of 117 patients with severe closed head injury were analysed. We put forward the CT diagnostic criteria of diffuse axonal injury (DAD)i.e. (1) single or multiple small intraparenchymal hemorrhages in the cerebral hemispheres (< 2 cm in diameter); (2) intraventricular hemorrhage; (3) hemorrhage in the corpus callosum; (4) small focal areas of hemorrhage adjacent to the third ventricle (< 2 cm in diameter); (5) brain stem hemorrhage. Our patients were divided into DAI group and non-DAI group according to the set of criteria. Traffic accidents were the main injury cause in patients with DAI. GCS on admission in patients with DAI were significantly lower than those in patients without DAI. The incidence of diffuse brain swelling in patients with DAI significantly higher than that in non-DAI patients, whereas the incidences of skull fracture and epidual hematoma were respectively significantly lower than those in non-DAI patients. There was no significant difference between the incidences of subarachnoid hemorrhage and subdual hematoma in the two groups. The incidence of poor outcome in DAI group was significantly higher than that in non-DAI group, although there was no significant difference between the mortalities in the two groups. Because DAI is a very important factor worsening the outcome of head-injured patient, it is very important to make a diagnosis as soon as we can. However, the clinical manifestations of DAI are not specific and DAI does not show directly on CT, so it is difficult to make a diagnosis. The CT diagnostic criteria of DAI we put forward now are practicable, though they are not perfect.