The main steps of lumbar puncture are as follows: 1. First, contraindications to this type of puncture should be excluded. If the patient has cranial hypertension, brain herniation, shock or local infection, the puncture cannot be performed. 2. The puncture point should be determined. The intersection of the highest point of the iliac crest bilaterally and the posterior midline is usually taken as the puncture point. 3. Assist the patient to assume a good position, usually requiring the patient to take a lateral recumbent position, then bend the hip, bend the knee, overflex the neck, clasp the knee with both hands, completely expose the lumbar region, and disinfect the area with a towel. 4. Perform layer-by-layer infiltration anesthesia on the puncture point. 5. Slowly enter the needle using the puncture needle until you feel a sense of the needle falling out, then pull out the The needle core is seen to drip out cerebrospinal fluid, at which point the pressure of the cerebrospinal fluid is quickly measured, as well as retained for relevant examination. Afterwards, the needle is slowly withdrawn, the puncture site is covered with gauze and fixed with adhesive tape, and the patient is asked to lie flat with the pillow removed for more than six hours.