The diagnosis of headache mostly requires detailed examination (location of headache, characteristics of headache, duration of onset, season of headache, presence of precipitating symptoms, relationship with postural changes, changes in characteristics of recent headache attacks and previous attacks, and family history, etc.) and cranial CT or MRI to exclude organic lesions before the diagnosis can be confirmed. However, headache may be related to many kinds of diseases, so meticulous differential diagnosis is needed. 1.Temporal arteritis: When giant cell arteritis occurs in the temporal and occipital arteries outside the skull (occipital or temporal arteritis), it can cause severe persistent headache, starting with pain in the local area and then becoming more diffuse. 2. vertebral artery thrombosis, with pain in the postauricular or low occipital region; 3. basilar artery thrombosis pain can disseminate to the occiput and sometimes to the forehead forehead. 4, Carotid aneurysms most commonly project pain to the eye, brow and forehead (atherosclerotic occlusions do not cause this symptom) 5, Intracranial aneurysms can cause radiating pain, and pain from damage to the posterior communicating artery often radiates to the eye. 6. Headaches caused by sinus obstruction or infection are located in the affected maxillary and frontal sinuses and are accompanied by skin tenderness in the corresponding area. Pain from the septal and pterygoid sinuses is located deep behind the midline of the nasal root and occasionally in the cranial vault (especially in pterygoid sinus disease) or other parts of the skull. Sinus pain attacks and relieves periodically, depending on whether the sinus flow is unobstructed. In patients with frontal and septal sinusitis, pain tends to increase during waking hours and gradually decrease when upright. In patients with maxillary and pterygoid sinusitis, on the contrary, a mechanism for the onset of pain has been discovered through this relationship: pain occurs when the sinus fills and is relieved when the sinus contents drain, and it depends on the location of the sinus drainage opening. The pain is aggravated by changes in sinus pressure caused by bending over, just as the infected sinus opening is open and blowing the nose aggravates the pain at the same time, the relative pressure of the obstructed organ decreases during descent of an airplane during flight and the patient often develops otalgia and headache, and sympathomimetic drugs such as dehydroepinephrine hydrochloride reduce edema and congestion and thus pain. However, if all purulent discharge disappears and pain persists, it may be due to obstruction of the sinus opening by a soft and wet mucosa and absorption of air from the obstructed sinus (vacuum sinus headache). When the air exchange is restored, the symptoms are alleviated. 7. Ophthalmogenic headache is a persistent pain generally located in the orbit, forehead and temporal region, often occurring in close maternity use of the eyes, mainly due to persistent contraction of extraocular, frontal, temporal and even occipital muscles caused by farsightedness and astigmatism (rarely myopia). Correction of refractive error may eliminate the headache. Headaches are induced by pulling on the extraocular muscles and iris during eye surgery. Patients with neurological disease presenting with diplopia or an eye patch covering one eye and forced to use the other eye often complain of prefrontal headaches. Another mechanism is associated with iridocyclitis and acute glaucoma. Both of these diseases lead to an increase in intraocular pressure, which causes persistent and unbearable pain in the eye area radiating to the forehead. Regarding ocular pain in general, although correction of visual acuity is more important, eye muscle fatigue is not as common a cause as one might think from the efficacy of wearing a large number of glasses to alleviate Tutone. 8. Headaches caused by cervical sphenopalatine ligament disease, muscle disease, and osteoarthritic disease can involve the ipsilateral occipital region and the back of the neck, and sometimes the temporal region and forehead. Injection of hypertonic saline into the affected ligaments, muscles and synovial joints can partially replicate the pain in these areas. This pain can be particularly frequent in adult life and can produce headaches due to rheumatism, hypertrophic arthritis, whiplash injuries, or after sudden flexion, extension, or rotation of the head in the neck. If the pain is arthritic in nature, stiffness and pain occur in the first movement field after a few hours of rest. Tactile pressure on the cervical muscles and other muscles in the cranial attachment point near the nodes produces pain, and fibromyalgia headache should be suspected. 9. Meningeal irritation headache (infection or hemorrhage) has an acute onset and a severe, diffuse, deeply located and persistent character with cervical tonicity, more pronounced in forward flexion. It is believed that increased intracranial pressure is related to the dilation and inflammation of meningeal vessels, chemical stimulation of pain receptors on large vessels and meninges such as 5-HT and plasma kinins, are more important factors for pain and neck extensor spasm. For example, a chemical type of meningitis due to an epidermoid cyst has normal cerebrospinal fluid pressure but severe headache. 10. Headache during lumbar puncture is characterized by stable occipito-cranial and frontal region pain, which occurs within minutes from lying to sitting position and relieves within minutes after lying down. It develops because of persistent leakage of cerebrospinal fluid into the lumbar tissues through the lumbar puncture hole, decreased cerebrospinal fluid pressure (often zero in the lateral recumbent position), and intrathecal injection of sterile saline to relieve the headache. Usually this type of headache is aggravated by compression of the jugular vein, but is not affected by finger pressure on one side of the carotid artery. In the upright position, low intraspinal pressure and negative intracranial pressure cause the brain to shift caudally and the dural attachment points and dural sinuses to be stretched. Spontaneous low cranial pressure headaches occur after sneezing, twisting, or sports injuries, presumably due to rupture of the arachnoid membrane traveling along the nerve roots. To penetrate after severe cervical tonicity and retrooccipital pain is rare, but sugar does not decrease, called aseptic or chemical meningitis, and this benign reaction must be distinguished from septic meningitis (bacterial infection caused by lumbar puncture) 11. Increased headache after lying down occurs in patients with chronic subdural hematomas and tumors, especially lesions in the posterior cranial fossa. Pseudotumor cerebri headache is also aggravated in the recumbent position. 12. Usually exertional is benign, but sometimes it can occur in patients with pheochromocytoma, arteriovenous malformation or other intracranial damage, and bending over can also induce headache.