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 or not, mainly based on acute onset, focal neurological deficit, comprehensive neurological deficit, symptoms and signs, 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 whether there are foci of responsible infarction. III.Assess the severity of stroke according to the neurologic deficit scale. Fourth, check the indications and contraindications to clarify whether thrombolytic therapy can be performed. V. Define the etiologic staging, refer to the TOAST staging criteria, and determine the etiology by combining the history, laboratory data, definitive lesions and vascular lesions, and other examination data. Etiological typing of ischemic stroke patients can help determine the prognosis, guide treatment and select secondary prevention measures. The above content is for reference only, specific medication and treatment please refer to the guidance of the doctor’s interview.