Alterations in the cerebral venous circulation as a cause of headache.

The alterations of the cerebral venous circulation are a rare but clinically important cause of headache. Although any process involving the cerebral veins or sinuses may cause headache, the most frequent and important are cerebral venous thrombosis and idiopathic intracranial hypertension. The headache of cerebral venous thrombosis does not have specific features and may be isolated; therefore, all patients with headache and risk factors for venous thrombosis should undergo the appropriate neuroradiologic examinations to rule out the diagnosis. In fact, early anticoagulant treatment may dramatically change the clinical outcome. Also idiopathic intracranial hypertension, if untreated, may have serious clinical consequences such as permanent visual loss. The pathogenesis of this disorder has not been clearly established and several possibilities involving the cerebral circulation are discussed.