ABSTRACT
Headache diagnosis is based on a complete and thorough history supplemented by general physical and neurological examinations. The American Academy of Neurology (AAN) has reviewed the use of electroencephalography (EEG) in headache diagnosis and found that many studies suffer from major flaws. Studies designed to determine if headache patients have an increased prevalence of EEG abnormalities give conflicting results. Magnetic resonance imaging (MRI) is preferred to computed tomography (CT) for the evaluation of headaches. Unless aneurysm, vasculitis, or arteriovenous malformation (AVM) is suspected, there is little reason to perform angiography when a patient has a normal neurological examination, a normal CT or MRI, and a history consistent with a benign primary headache disorder. Headache of sudden onset and extended duration may indicate an subarachnoid haemorrhage (SAH) or a sentinel headache without haemorrhage. Basilar migraine should be suspected in the presence of syncope, diplopia, vertigo, ataxia, change in mental state, and confusion.
