[Cerebral vasculitis, a diagnostic labyrinth].

• A diagnosis of cerebral vasculitis is frequently considered in patients with new or progressive neurological symptoms for which there is no other explanation.- A clinician considering a diagnosis of cerebral vasculitis should be well aware of alternative diagnoses, since these are generally more common.- Several consecutive examinations are required for diagnosing cerebral vasculitis, because there is no diagnostic procedure that is highly sensitive as well as highly specific.- The added value of the different procedures may depend on the type of blood vessels involved.- Standard MRI examinations are sensitive but not specific.- Special MRI techniques now make it also possible to make images of the vessel wall itself.- Catheter angiography remains important, especially when non-invasive angiographic techniques do not reveal any abnormalities.- Brain biopsy can provide proof of cerebral vasculitis and also serves to exclude mimicking conditions.