Subdural hematomas. Causes, types, consequences and forensic aspects

This review surveys subdural hematomas, including general knowledge presented in the literature as well as own experiences. Main topics are: frequency, causes, types, clinical symptoms, development, risk factors, prognosis of subdural hematomas and injured structures predominantly responsible for such bleedings. Focal points of the presentation are forensic aspects, not clinically important details. Generally, a reduction of the diagnosis as subdural hematoma seems to be problematic. Firstly a subdivision in hematomas in patients with relevant injuries of the cerebral tissue (like contrecoup-lesion) and ... without cerebral injury (pure, respectively isolated) is necessary, because the predominant causes of such cases differ, and (forensic) experiences with one of these classes cannot be completely transferred to the other. Secondly, in pure subdural hematomas the source of bleeding, i.e. the type of injured vessel should be characterized - if ever possible. Ruptures of cerebral bridging veins are generally looked at as traumatically caused. In contrast, following clinical literature hemorrhages from cortical arteries sometimes occur spontaneously. This aspect seems to be not sufficiently discussed in forensic literature. An excursion to traumatic subdural hygromas rounds off this presentation.