Head CT plain scan without abnormality indicates that: 1. It can be judged that the patient does not have problems such as cerebral hemorrhage, intracranial tumors, intracranial occupancy, etc.; 2. If the patient has head CT because of problems such as poor limb movement or speech clumsiness, visual field defect, choking on drinking water, etc., the lack of abnormality on head CT plain scan does not indicate that the patient does not have intracranial lesions. The patient ruled out cerebral hemorrhage, this symptom should be considered ischemic cerebrovascular disease, such as transient cerebral ischemia or cerebral infarction and other diseases. Because the patient’s onset is still short, the lesion is not visualized on the cranial CT, so the cranial CT scan is normal. The patient should also consult the neurology department for symptomatic management.