[Cerebral venous thromboses. Clinical diagnosis].

Cerebral vein thromboses constitute a major part of cerebral venous disease. They can occur at any age, generally in young subjects, and are due to a variety of causes, although no aetiology can be detected in one quarter of cases. They generally occur in the superior sagittal sinus and transverse sinuses, while involvement of the deep veins and posterior fossa veins is much less common. The symptoms consist of varying degrees of signs of intracranial hypertension (ICH) and focal and/or epileptic signs. The onset may be sudden, subacute or chronic, simulating a cerebral vascular accident, an abscess, encephalitis, a tumour or benign ICH. Radiological investigations, especially MRI and angiography, are the key to the diagnosis. A fatal outcome is observed in 10% of non-infectious forms. The benefit of heparin therapy, although controversial for a long time, has now been clearly established.