Subarachnoid haemorrhage is `a leakage of blood that occurs over the surface of the brain, most commonly originating from a weakened artery deep within the brain' (Foulkes 2004: 5). This weakened artery can then form `a balloon-like swelling called an aneurysm [and] the haemorrhage occurs when the aneurysm wall tears because of the pressure of blood' (Brain and Spine Foundation 2002: 4). Because aneurysms often resemble small red berries (or balloons) they are also sometimes referred to as `berry aneurysms'. More detailed medical information can be found elsewhere (e.g. Lindsay and Bone 1997; Brain and Spine Foundation 2002; Foulkes 2004).