The precursor of sobriety in patients with cerebral edema is the reduction or disappearance of clinical symptoms, such as severe headache, dizziness, head swelling, nausea, vomiting, and other symptoms are reduced, or even substantially improved. In addition, the neurological symptoms caused by cerebral edema gradually improve, and neurological functions begin to recover, such as the number of seizures decreases or even disappears. Some patients with blurred vision and vision loss due to cerebral edema may have clear vision when the optic nerve starts to recover. Therefore, if the patient has brain cell and brain nerve damage, early intervention is needed to avoid prolonged cerebral edema triggering nerve damage or even aggravating the damage.