Evaluation of acute headaches in adults

Classifying headaches as primary (migraine, tension-type or cluster) or sec ondary can facilitate evaluation and management. A detailed headache histor y helps to distinguish among the primary headache disorders. "Red flags" fo r secondary disorders include sudden onset of headache, onset of headache a fter 50 years of age, increased frequency or severity of headache, new onse t of headache with an underlying medical condition, headache with concomita nt systemic illness, focal neurologic signs or symptoms, papilledema and he adache subsequent to head trauma. A thorough neurologic examination should be performed, with abnormal findings warranting neuroimaging to rule out in tracranial pathology. The preferred imaging modality to rule out hemorrhage is noncontrast computed tomographic (CT) scanning followed by lumbar punct ure if the CT scan is normal. Magnetic resonance imaging (MRI) is more expe nsive than CT scanning and less widely available; however, MRI reveals more detail and is necessary for imaging the posterior fossa. Cerebrospinal flu id (CSF) analysis can help to confirm or rule out hemorrhage, infection, tu mor and disorders related to CSF hypertension or hypotension. Referral is a ppropriate for patients with headaches that are difficult to diagnose, or t hat worsen or fail to respond to management.