Acute aneurysmal haemorrhage presenting as space occupying subdural haematoma

With this report on 3 cases of subarachnoid haemorrhage presenting like a space-occupying acute subdural haematoma the authors want to remind clinicians of the danger of overlooking an intracranial aneurysm in cases of acute subdural haematomas, when relying diagnostically only on CT findings. Frequency and possible mechanism of this phenomenon is discussed taking into account data from the literature. In any acute subdural haematoma without clear traumatic aetiology or with symptoms and signs in the history which could indicate the possibility of a subarachnoid haemorrhage should angiography be done.