Right MCA aneurysm (3yr old male)

There is an aneurysm arising from the proximal right middle cerebral artery. Reduced flow in the right middle cerebral artery is demonstrated on the MRA study. Within the right sylvian fissure there is subarachnoid haemorrhage demonstrated. Overlying the right frontal convexity there is a high T2 intensity subdural effusion. subarachnoid haemorrhage is demonstrated in the left sylvian fissure in addition, and also the anterior interhemispheric fissure and occipital horns, and the 4th ventricle. There is subdural haemorrhage around the right occipital lobe. No abnormality is demonstrated within the brain parenchyma. No subdural haemorrhage is demonstrated around the left cerebral hemisphere or in the posterior fossa.