A slight widening of the extracerebral space in the frontal-temporal region on both sides is an imaging description of a change that is sometimes detected during a cranial CT or cranial MRI. This condition is most commonly seen in elderly patients, and there are several possibilities: 1, the patient has brain atrophy, elderly patients are often due to degenerative brain changes, resulting in cerebral cortex atrophy, which tends to be more pronounced in the frontal and temporal lobes, and then a layer of gap between the brain parenchyma and dura mater of the skull can be found, which is filled with cerebrospinal fluid. 2, there is a history of traumatic brain injury, if the patient has a history of traumatic brain injury resulting in chronic subdural hemorrhage, the blood absorption can lead to frontal and temporal extracerebral space. After the blood is absorbed, it will lead to subdural fluid in the frontotemporal region, which is also shown as a slightly wider extracerebral space on imaging.