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Aneurysm and Subarachnoid Haemorrhage

Although CT angiography is more and more widely used as diagnostic tool in SAH, DSA remains a useful technique. Indeed DSA is mandatory in patients with SAH and negative angio-CT, and in all other doubtful cases. Angiography is also necessary in order to perform an endovascular treatment. Sometimes, after a SAH a first angiogram may be normal due to spasm, haematoma or in case of a real perimesencephalic haemorrhage. The need for a second angiogram is discussed. Finally some aspects concerning the aneurysmal growth and rupture are also discussed.