We often hear derisive comments like “sick in the head”. Those who are called “sick” know that they are not sick, or laugh it off or say “you are the one who is sick” back. However, if there is something really wrong with the brain, it is not so easy. Once the need for cranial treatment, not only the patient, even the medical staff feel quite tricky. In recent years, the emergence and development of neurointerventional treatment methods, so that some cranio-cerebral disorders can be treated without surgery. The following is a brief introduction to the reader. Neurointerventional therapy is a method of direct treatment of cranio-cerebral disorders under x-ray television surveillance. To use an analogy, the blood vessels of the human body are like the intertwined rivers and lakes, and interventional therapy is to put “small boats” of different sizes and purposes with therapeutic effects under the control of “wired” or “wireless”. Under the control of “wired” or “wireless”, these “rivers” are transported to the “dock” of the disease, thus achieving the purpose of treatment. For treatment, femoral artery puncture is usually used. Under x-ray television surveillance, a 2 mm inner diameter introducer tube is inserted through the aorta into the carotid or vertebral artery, the vessel supplying the skull and brain. Then, a very flexible microcatheter with an internal diameter of 1 mm or finer is selectively inserted through the guide tube into the relevant intracranial artery to the site of the lesion. Finally, depending on the nature of the lesion, different methods such as embolization, drug injection, dilation and other operations are then used to achieve the treatment goal. Generally speaking, neurointerventional treatment is less invasive, less painful, less dangerous, and has a wide range of indications. At present, it is mainly used clinically to treat the following diseases: cerebrovascular malformation This is a common cause of intracranial hemorrhage in adolescents, with a vicious and sudden onset, more bleeding when open, more dangerous and can cause disability. Interventional treatment can be performed by selectively inserting a microcatheter into the blood supply artery of the malformed vessel and then injecting various different embolic agents to partially, mostly or completely embolize the malformed vascular mass. Some patients can be cured in a single session, while others require multiple sessions. Cerebral aneurysm This is the leading cause of death from subarachnoid hemorrhage in middle-aged adults, and recurrent hemorrhage leading to death occurs frequently and must be operated on promptly. Some huge aneurysms that were previously inoperable can now be treated with interventional methods. A microcatheter is delivered to the aneurysm, through which an electrolytic detachable spring coil is inserted into the aneurysm and coiled into a basket shape, and electricity is applied to uncoil the coil. Several more coils are inserted until the aneurysm is completely occluded, while leaving the aneurysm-carrying artery unobstructed. Cerebral thrombosis This is a common type of “stroke” in the elderly. It can cause hemiplegia and slurred speech due to the obstruction of cerebral blood vessels by thrombus. In recent years, drugs have been developed to dissolve the thrombus, such as recombinant streptokinase and urokinase, but the effect is not satisfactory after intravenous injection. The latest method is to use interventional treatment by inserting a microcatheter into the thrombus blocked vascular site and then injecting the drug, so that the concentration of the drug at the lesion site is significantly increased, often with unexpected results. Carotid cavernous sinus fistula Protrusion, throbbing, and localized congestion of the eye can occur in some patients after a head injury and is called a carotid cavernous sinus fistula. In the past, craniotomy or neck surgery was required, but the results were not reliable. Nowadays, an interventional method is used in which a detachable balloon catheter is selectively inserted into the fistula where the artery and vein meet, and the filling balloon completely occludes the fistula while keeping the cerebral artery blood flowing. This method is safe, reliable, and has immediate results. Intracranial meningioma This is a common benign intracranial tumor. It is a common benign intracranial tumor and is very risky to operate because of the rich blood supply. Interventional radiological techniques can be used to occlude the vascular network and main blood supply arteries within the tumor by injecting a 200 micron diameter embolus through a microcatheter with an internal diameter of less than 1 mm. In this way, the surgery can be performed with “no blood” or “little bleeding” and achieve perfection. Intracranial malignant tumors, such as glioma and brain metastases, are prone to recurrence after surgical resection and radiotherapy, so chemotherapy is generally used. The efficacy of chemotherapy is limited because of the high systemic reaction of chemotherapeutic drugs. Interventional techniques are used to selectively insert micro-catheters into the blood vessels supplying the tumor and infuse chemotherapy drugs, which is called “super-selective intra-arterial chemotherapy”. This method can increase the local drug concentration of the tumor by 50 times, reduce the systemic side effects and toxic reactions, significantly improve the efficacy, reduce the patient’s pain, and prolong the patient’s survival.