Original Resolution: 1429x2246 Surgery Of Middle Cerebral Artery Mca Aneurysm Springerlink Computed tomography (also cat or ct scan) of the brain (cerebral hemispheres, cerebellum and brain stem.) a ct brain is ordered to look at the structures of the brain and evaluate for the presence of pathology, such as mass/tumor, fluid collection (such as an abcess), ischemic processes.