Lumbar puncture is one of the commonly used examination methods in neurology, which is mainly used for the diagnosis of conditions, and can be used to check central nervous system diseases and observe cerebrospinal fluid changes. 1. Mainly by checking the nature of cerebrospinal fluid, it provides the basis for the diagnosis of cerebrovascular lesions, brain tumors, encephalitis, meningitis and other neurological diseases. 2. It can also measure the intracranial pressure when it is suspected that there is an abnormality in the intracranial pressure. 3. It can also be used to know whether there is obstruction in the subarachnoid space. 4. Sometimes it is also used for intrathecal drug injection to treat the corresponding diseases. 5. By dynamically observing the changes in cerebrospinal fluid, it is helpful in determining the progress of the disease, prognosis, and adjustment of the program.