Non contrast CT scan through the brain demonstrates no acute abnormality. Extensive periventricular low density is in keeping with small vessel ischaemic change, most likely chronic. On the right a rounded density is seen in the sylvian fissure, which appears to be in continuity with the right MCA and contains a focus of peripheral calcification. The supraclinoid ICA on the left is bulbous. No evidence of subarachnoid haemorrhage.