According to the guidelines, the diagnostic process of ischemic stroke is as follows, with a total of five steps: i. Determine whether it is a stroke, mainly based on acute onset, focal neurological deficit, global neurological deficit, signs and symptoms, and duration, and exclude non-vascular diseases. Second, to determine whether it is ischemic stroke, patients with suspected stroke should undergo cranial CT or magnetic resonance examination to exclude hemorrhagic stroke and other lesions, and to clarify the presence or absence of foci responsible for infarction. III. Assess the severity of stroke according to the Neurological Impairment Scale. IV. Check the indications and contraindications and clarify whether thrombolytic therapy can be performed. V. Define the etiological staging and determine the etiology with reference to TOAST staging criteria, combined with medical history, laboratory data, definite lesions and vascular lesions and other examination data. Etiological staging of patients with ischemic stroke can help determine the prognosis and guide the treatment and selection of secondary prevention measures. The above content is for reference only. Please refer to the doctor’s guidance for specific medication and treatment in face-to-face consultation.