Acute pure spontaneous subdural haematoma from ruptured intracranial aneurysms.

SUMMARY: Acute subdural haematoma (ASDH) is rarely caused by an aneurysmal rupture. We report four cases of pure acute subdural haematomas caused by ruptured intracranial aneurysms. Aneurysms were localized in the posterior communicating artery in two cases, in the anterior communicating artery in one case and in the middle cerebral artery in one other case. Possible mechanisms for this type of aneurysmal bleeding are discussed. A good prognosis for these patients can be expected with rapid evacuation of the haematoma (in case of high intracranial pressure and midline structure shift), and treatment of the aneurysm (surgical clipping or endovascular treatment). Our report demonstrates the utility of angiography in the evaluation of nontraumatic acute subdural haematomas. Angiography has to be performed before haematoma evacuation or just after if the patient requires urgent surgery in case of intracranial hypertension. Aneurysms may require surgical clipping or endovascular treatment.