Preschooler after cardiac arrest

CT and CT angiogram of giant intracranial aneursym
Axial CT without contrast of the head (above) shows a round mixed density lesion just to the right of the third ventricle along with diffuse subarachnoid hemorrhage and cerebral edema. Axial (below left) and sagittal (below right) CT angiogram shows the lesion to arise from the A1 segment of the right anterior cerebral artery.

The diagnosis was giant intracranial aneurysm which had ruptured causing subarachnoid hemorrhage and diffuse cerebral edema.