I. Overview Vascular malformations include arteriovenous malformations and arteriovenous fistulas. Arteriovenous malformations have thickened blood supply arteries, malformed vascular masses, and tortuous and dilated draining veins. Under normal circumstances, the capillaries between the arteries and veins show uniform and consistent staining on imaging, and no vessels are visible. In arteriovenous malformations, the capillaries between the arteries and veins are very thick, uneven in thickness, disorganized, and tortuous forming a vascular mass. If the artery does not return to the vein through the capillaries, it is called an arteriovenous fistula. Arteriovenous malformations can occur in the limbs and in the skull, and arteriovenous fistulas can occur after trauma and after tumor invasion of the vessels. In the lungs, there are mostly congenital arteriovenous fistulas, which show local tissue ischemia, hypoxia and increased venous pressure because of the direct return of arteries to veins. Second, diagnosis Arteriovenous malformations are mainly due to the finding of soft tissue skin masses, and the diagnosis can be confirmed by ultrasound or angiography. Pulmonary arteriovenous fistulas are most commonly seen in children and adolescents, and can show signs of hypoxia, such as cyanosis and shortness of breath after activity, which can be diagnosed by CTA or angiography. The treatment of vascular malformation in the past can only be done surgically before interventional treatment. Surgery for arteriovenous malformation of the limb is very traumatic, bleeding and sometimes difficult to determine the scope of surgery, so it is easy to recur. Surgical treatment of pulmonary arteriovenous fistula involves cutting away part of the good lung tissue, which is certainly not conducive to the developmental growth of the child. Interventional treatment is a very effective treatment for arteriovenous malformations, without incisions, safe, with few complications, minimally invasive and, crucially, effective. Angiography allows us to determine very clearly the extent of the malformation, the extent of the blood supply arteries and the draining veins, and the size of the arteriovenous fistula. By selecting the appropriate size and type of embolization material, we can embolize the malformed vascular mass or completely block the arteriovenous fistula, and the patient’s symptoms will improve soon after the treatment. If the mass in the limb is significantly reduced. In the case of pulmonary arteriovenous fistulas, the oxygen saturation of the child rapidly increases to normal levels after the fistula is plugged, and the lips, which were blue due to lack of oxygen, immediately become rosy, which can be said to have an immediate effect. In conclusion, interventional treatment is a very effective means of treating vascular malformations, but we must carefully study the angiographic situation, and pay attention to the distal artery visualization and the formation of collateral circulation, if necessary, we can first temporarily block the arterial blood supply with a balloon, and observe the tolerance of the distal limb or organ to ischemia, so that we can decide whether to embolize, and at the same time, we must carefully choose the appropriate embolic agent, otherwise it may also Otherwise, complications such as distal limb necrosis and ectopic embolism may occur.