CLINICAL-STUDIES ON DIFFUSE AXONAL INJURY IN PATIENTS WITH SEVERE CLOSED-HEAD INJURY

Objective To discuss the clinical criteria for diagnosing diffuse axon al injury (DAI). Methods Clinical and computed tomographic features of 117 patients with severe closed head injury were analyzed. The author s preliminarily put forward CT diagnostic criteria of DAI, that is, 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); and 5) brain ste m hemorrhage. All patients were divided into two groups, DAI and non-D AI group, according to the criteria. There were 42 patients in the DAI group and 75 patients in the non-DAI group. The injury causes, Glasgo w coma scale (GCS) scores on admission, coexisting injuries and outcom es were compared between the two groups. The relationship between DAI and the outcomes in the patients with severe head injury was analyzed. Results Traffic accident was the main injury cause in the cases of DA I. GCS scores on admission in patients with DAI were significantly low er than those in patients without DAI. The incidence of diffuse brain swelling (DBS) in the DAI group was significantly higher than that in the non-DAI group, whereas the incidences of both skull fracture and e pidural hematoma (EDH) in the DAI group were significantly lower than those in non-DAI group. There was no significant difference between th e incidence of subarachnoid hemorrhage (SAH) and subdural hematoma (SD H) in the two groups. The incidence of poor outcome in the DAI group w as significantly higher than that in the non-DAI group, although there was no significant difference between the mortalities in the two grou ps. Conclusions Because DAI is a very important factor worsening the o utcome of patients with head injury, it is essential to make a diagnos is as soon as possible. The clinical manifestations of DAI, however, a re not specific and DAI does not show directly on CT scans, so it is d ifficult to make a definite diagnosis. The CT diagnostic criteria of D AI put forward in this article are practicable, though they are by no means perfect.