The severity of vasospasm detected by intracranial CT depends on the etiology. If it is due to reversible cerebral vasoconstriction syndrome, it is usually not serious; however, if it is due to subarachnoid hemorrhage, it is more serious. 1. Reversible cerebral vasoconstriction syndrome: mainly due to changes in cerebral vascular tone, during the onset of the patient may have a mild headache and symptoms of blurred vision. The condition is generally not serious and has a good prognosis through timely treatment. 2. Subarachnoid hemorrhage: when the amount of subarachnoid hemorrhage increases, it will cause vasospasm. The disease itself is more serious, if not treated in time, the patient may suddenly faint, coma, and fall into a loss of consciousness, and in serious cases, it may also threaten the life, and the morbidity and mortality rate of this kind of disease is also relatively high. When cerebral vasospasm is detected, it is necessary to further improve the examination to understand the cause of the disease before treatment is carried out.