Moyamoya disease, also known as spontaneous basilar artery ring occlusion, is a disease characterized by slow intimal thickening of the arteries at the end of the internal carotid artery and its branches at the beginning of the anterior and middle cerebral arteries, gradual narrowing of the arterial lumen to occlusion, and compensatory dilation of the penetrating arteries at the base of the brain. The shape of the dilated blood vessels on imaging resembles the curl of smoke in a chimney, so the Japanese image is called Moyamoya disease. It can cause both ischemic and hemorrhagic strokes. It usually occurs in children younger than 10 years old and adults between 30 and 40 years old, with ischemic attacks as the first symptom and hemorrhagic attacks as the first symptom in adults. The diagnosis of smog is based on the following criteria: 1) severe stenosis or occlusion of the beginning of the internal carotid artery and/or the anterior cerebral artery (ACA) and/or the beginning of the middle cerebral artery (MCA); 2) abnormal vascular network around the occluded artery during the arterial phase; 3) the above lesions are bilateral (if one side of the lesion is consistent with the other side of the lesion in children, severe stenosis can also be diagnosed). The diagnosis can also be confirmed if one side of the child is eligible and the other side is severely stenosed). Treatment of smog is mainly surgical. Treatment for hemorrhagic smog is the same as for ischemic smog. The aim of treatment for hemorrhagic smog is to prevent rebleeding by increasing the blood supply to the cerebral cortex and reducing the blood supply load to the smog vessels at the base of the brain; the aim of treatment for ischemic smog is to increase the blood supply and reduce ischemic attacks. There are several surgical methods to reconstruct blood flow to the brain tissue, including direct revascularization, indirect revascularization, and combined direct and indirect revascularization. Direct revascularization is mainly superficial temporal artery-middle cerebral artery bypass; indirect revascularization includes cerebral-dural-artery apposition, cerebral-temporal muscle apposition, cerebral-retinal apposition, and cranial multiple borings, etc. Among them, superficial temporal artery-middle cerebral artery bypass is considered to be the preferred and effective treatment method.