Nontraumatic headaches in the Emergency Department: a systematic approach to diagnosis and controversies in two "big ticket" entities.

Headache is a very common presenting complaint in the Emergency Department (ED). While the vast majority of these have benign or self-limited etiologies, there are several life or organ threatening causes that must be excluded. This paper describes a systematic approach to the history and physical examination in these patients. Evidence-based recommendations for which patients should receive imaging in the ED are reviewed. Current diagnostic approaches and controversies in meningitis and subarachnoid hemorrhage are discussed.