Intracranial pressure is the increase of the tensile forces exerted within the cranium. The latter being inextensible, if one of the structures of the brain increases in volume without any of the other structures compensating by reducing their volume, intracranial hypertension develops. Intracranial pressure can thus be due to increased brain tissue structures as is the case in tumors, such as the accumulation of blood in a cerebral hemorrhage, intracranial thrombophlebitis, or cerebral hematoma, or an increase in volume of the cerebrospinal fluid, called hydrocephalus, which is not sufficiently absorbed. Intracranial hypertension is serious because of the pressure on fragile structures which may be subject to irreversible damage. The symptoms are represented by headache, vomiting, and visual disturbances, including double vision.