Focal atrophy on CT: region of low density within the brain parenchyma or as focal dilation of a part of the ventricle or subarachnoidal space.
Post-traumatic atrophy: 3-6 months following the trauma. Focal atrophy is common when a hemorrhagic contusion is present in the acute phase. Often located peripherally, predominantely involving the frontal lobes. When involves the periventricular space then it can resemble proencephaly.
Post -inflammatory atrophy: Post inflammatory atrophy secondary to brain abscess is most often due to necrosis of the brain.
Post-infarction atrophy: can be ischemic or hemrorrhagic. Tends to be confined to the supply areas of major arteries. Post ischemic infarcts tend to be evident on CT as early as 3-6 months post event.
Cerebral hemiatrophy: Davidoff-Dyke syndrome
Manisfests itselfe during adolesence. It developes secondary to neonatal or intrauterine vascular occlusion, resulting in massive infarction.
May primarily involve the white or gray matter but usually it involves both.
Diffuse form of cerebral atrophy although there is dominant involvement of the gray matter.
CT findings are not specific, the most common findings are symetrically enlarged ventricles with prominence of the cortical sulci.
Most commonly seen in females. The atrophic process although diffuse, predominantly involves the temporal and frontal lobes.
Neoplasi and metabolic disorders