J Headache Pain (2006) 7:422–432 DOI 10.1007/s10194-006-0347-6

Abstract Headache is one of the most common outpatient pain con-ditions encountered in both physi-cian offices and emergency depart-ments. Establishment of an accurate diagnosis, accomplished only by a thorough history followed by a physical examination, is critical before treatment can be initiated. Many patients undergo evaluation with computed tomography and more recently magnetic resonance imaging to exclude important abnormalities. It is known that a lit-tle percentage of patients showed significant neuroradiologiacal abnormalities and the rate of signif-icant intracranial abnormalities in patients with headache and normal neurological examination exists