Intracranial aneurysm is not a solid tumor, but an abnormal topical bulge in the arterial wall caused by abnormal vascular changes, which is the weakest part of the vessel wall. Aneurysms may rupture and bleed under the impact of blood flow and changes in blood pressure. Due to the atypical symptoms before rupture but dangerous and rapid development of the disease after rupture, many patients die before they are sent to the hospital in time. This makes aneurysm a real invisible killer. It is also known as a “time bomb” in the intracranial cavity.