(I) Atherosclerotic thrombotic cerebral infarction 1. Diagnostic criteria (1) Often develops in a quiet state. Yang Mingjian, Department of Neurology, Liaocheng City No. 4 People’s Hospital (2) Most of the onset without obvious headache and vomiting. (3)The onset of the disease is slow, mostly progressing gradually or in stages, mostly related to cerebral atherosclerosis, but also can be seen in arteritis, blood diseases and so on. (4) Generally, consciousness is clear or mildly impaired within 1 to 2 days after onset. (5) There are symptoms and signs of internal carotid artery system and/or vertebral a basilar artery system. (6) CT or MRI examination should be performed. (7) Lumbar puncture cerebrospinal fluid should generally not contain blood. 2. Clinical staging (1) Traditional staging ①Complete type: the condition peaks within 6 hours of disease onset, often with complete hemiparesis, and the condition is generally more serious, even coma. ②Progressive type: limited cerebral ischemia symptoms progress gradually, with stepwise aggravation, which may last for more than 6 hours to several days. (iii) Slowly progressive type: symptoms still progress after 2 weeks of disease onset, often associated with reduced cerebral perfusion due to systemic or local factors, poor compensation of collateral circulation, and gradual expansion of thrombus to the proximal part of the heart, etc. This type should be associated with intracranial ischemia. This type should be distinguished from intracranial occupying lesions such as tumor or subdural hematoma. ④ Reversible ischemic neurologic deficit (RIND): once called fully recoverable stroke, because of its clinical features of ischemia-induced neurologic symptoms, signs generally exceed 24 hours, the longest can persist for 3 weeks, and then return to normal without sequelae. In fact, it is a kind of infarction in the site of better blood supply, and with the compensation of collateral circulation, the function can be restored due to. (2) OCSP typing ①Total anterior circulation infarction (TACI): manifested by the triad of symptoms, i.e., the manifestations of the complete middle cerebral artery syndrome: impairment of the higher neural activity of the brain; homonymous hemianopsia; and hemianopic motor and/or sensory deficits. (ii) Partial anterior circulation infarction (PACI): two of the above triad of signs, or only high-level neural activity deficits, or sensory-motor deficits are more limited than TACI. ③ Posterior circulation infarction (POCI): manifested by various degrees of vertebrobasilar syndrome. ④Lacunar infarction (LACI): manifests as lacunar syndrome. Mostly small lacunar foci caused by lesions of the basal ganglia or small penetrating branches of the pons. (3) CT typing: cerebral infarction, cerebellar infarction and brainstem infarction according to anatomical location. Cerebral infarction can be divided into: ① large infarction: more than one lobe, more than 50mm. ② Middle infarction: less than one lobe, 31-50mm. ③ Small infarction: 16-30mm. ④ Cavernous infarction: less than 15mm. (B) Cerebral embolism 1, mostly acute onset. 2. 2.There are no precursor symptoms. 3.Generally conscious or with transient consciousness disorder. 4.Signs and symptoms of carotid artery system and/or vertebral basilar artery system. 5.Lumbar puncture cerebrospinal fluid usually does not contain blood, if there are red blood cells can be considered hemorrhagic cerebral infarction. 6.The source of the embolus can be cardiac or noncardiac, and it can also be accompanied by embolic symptoms of other organs, skin, mucous membranes and so on at the same time. (C) Cerebral watershed infarction 1. It is mostly caused by insufficient perfusion of cerebral artery due to hypotension and hypovolemia in body circulation. 2. It is characterized by limited ischemia between adjacent larger arterial blood-supplying areas in the brain (limbic zone). 3.Corresponding neurological dysfunction occurs, usually without consciousness disorder, and the prognosis is good. 4. Imaging examination usually reveals focal infarction in the adjacent lobe area. (D) Cavernous infarction 1, the onset of hypertensive atherosclerosis, acute or subacute onset. 2. Most of them do not have consciousness disorder. 3. CT or MRI examination should be carried out to clarify the diagnosis. Clinical manifestations are not serious, and the more common ones are pure sensory stroke, pure motor hemiparesis, ataxic hemiparesis, dysarthria, clumsiness of the hand syndrome or sensory-motor stroke. (Asymptomatic infarction is a vascular disease without any cerebral or retinal symptoms, which is only confirmed by imaging, and the clinical diagnosis can be decided on a case-by-case basis.