Diagnostic testing and secondary causes of headache

A complete headache history with neurological and general physical examinations, as appropriate, will usually suffice to diagnose the vast majority of headaches without the need for diagnostic testing. However, since over 300 different types and causes of headache have been identified, some of which are potentially life-threatening, judicious use of testing is essential to distinguish primary from secondary headaches. This chapter reviews general indications and studies available for diagnostic testing in adults and then the following contexts: headaches and a normal neurological examination, migraine, and acute severe new-onset headaches.