The head is always cloudy in the following situations: 1, abnormal blood pressure in the short term, blood pressure rises too quickly in the short term, or there is no timely intervention of hypertension, can have the symptoms of head cloudiness. In addition to the above-mentioned performance, there can also be hand numbness, back sleepiness, neck stiffness, etc. Cervical spine magnetic resonance examination can make a clear diagnosis. 3, posterior circulation ischemia, which refers to transient ischemia of the vertebral basilar artery system. system, or infarction of brainstem or cerebellum. These patients are prone to dizziness and lightheadedness, and some of them may have unstable walking, etc. The diagnosis can be made by cranial MRI and cranial angiography.