Aetiology and risk factors
An aneurysm is a localised swelling or dilation of an artery caused by weakening of the
arterial wall (Marcovitch 2010). In the cerebralvascular system, aneurysms usually occur at the joins and on the large arteries that make up or branch off from the circle of Willis (Hickey2009). The exact pathophysiological reasons for aneurysm formation are largely unclear,although risk factors have been identified(Table 1). It has been suggested that there is apossible link with the structure of the arteries,in particular the vessel walls, which are thinner
compared with arteries of the same size
elsewhere in the body (Greenberg 2010).
Complete time out activity