Only some patients will have postoperative headache for the following four reasons: (1) Headache at the surgical incision: This kind of headache, mainly located at the incision, is mild and can be gradually relieved after the removal of stitches, but there are also pains caused by the tension of the incision stitches or scar irritation of the greater auricular nerve or greater occipital nerve. (2) Headache caused by incisional infection: the pain is heavy and obvious, and it is a continuous jumping pain. Local inflammatory manifestations of redness, swelling and heat are seen when the incision is examined. (3) Headache caused by intracranial infection: This kind of headache is combined with meningeal irritation, fever, cervical tonicity, nausea and vomiting, and a wide range of pain. Most of these headaches are caused by infections after craniotomy and meningeal ganglion injection therapy. It can be confirmed by lumbar puncture for cerebrospinal fluid. (4) Low cranial pressure headache: It is mostly caused by physical weakness and excessive cerebrospinal fluid released during surgery. This kind of headache is obviously related to body position, and the pain is aggravated when sitting or standing, and reduced or disappeared after lying down.