Pathological brain atrophy, depending on the cause, can range from early to severe for months to decades. Cerebral atrophy is the atrophy of brain tissue due to organic lesions from various causes. The pathology is characterized by a reduction in the volume of brain tissue, a decrease in the number of cells, and an enlargement of the ventricles and subarachnoid space. Cerebral atrophy is not an isolated disease, but a neuroimaging manifestation of many diseases, such as cerebrovascular disease, encephalitis, traumatic brain injury, long-term heavy alcohol consumption, and long-term exposure to toxic substances. Patients mainly present with cognitive impairment and personality changes. Some elderly people can also develop brain atrophy as they get older and have severe cerebral arteriosclerosis, but there are no obvious clinical symptoms, and it is often during CT or MRI examinations that brain tissue volume reduction and ventricular enlargement are found. The specific time needed from early stage to principle is variable and may be several months or years. Cerebral atrophy should be treated promptly once detected, and the degree and speed of recovery from late treatment is worse than for those treated early.