Headaches can be of various natures, such as vague dull pain, pins-and-needles pain, and in some patients, fluctuating distension or persistent dull pain. In the case of patients with subarachnoid hemorrhage, it may also manifest as blast-like pain. Patients with cerebral hemorrhage can have unbearable pain, and patients with encephalitis can also exhibit blast-like pain in the forehead, making it unbearable. The direction of the disease can be clinically determined by the nature of the headache, for example, in patients with chronic distension, intracranial occupying lesions or venous sinus thrombosis are most often considered.