Brain aneurysm treatment. Coloured 3D computed tomography (CT) scan and angiogram, showing part of the treatment of an aneurysm in the arteries of the brain of a 40-year-old man. The patient was being treated for a brain haemorrhage, and scans showed the presence of an aneurysm (orange) of the anterior communicating artery in the brain. The arteries are shown in white here. An aneurysm is a weakening of the blood vessel walls. The treatment method involved the insertion of coils into the aneurysm. This was insufficient to completely treat the aneurysm, and surgery as also required with the use of a clamp (red). This image, a still from a video CT sequence, shows the clamp being used.