Imaging "Worst Headache of My Life" Part 1

Conditions in Which the Initial CT Is Often Positive

Peter G. Kranz, MD; James M. Provenzale, MD


Appl Radiol. 2013;42(7):19-23. 

In This Article


Headaches are a common problem and account for over 2 million visits to the emergency department every year. Most causes are benign, however, there are serious etiologies of headaches requiring care. Although noncontrast head CT (NCT) is the most common initial imaging test for patients presenting with the condition, causes sometimes do appear as abnormalities on NCT. In Part 1 of this two-part series, the authors focus on the use of NCT to identify potentially life-threatening diseases that commonly produce positive findings.

Nevertheless, several serious and potentially life-threatening etiologies of headache can and do cause patients to present to the ED. Physicians are tasked with differentiating the benign causes from the more serious, and imaging often plays a major role in making this distinction.

Noncontrast head computed tomography (NCT) is the most common initial imaging test ordered for headache patients presenting to the ED.[1] In most cases, this initial NCT will be normal. However, several potentially life-threatening causes of headache do appear as abnormalities on NCT, and these manifestations can range from subtle to highly conspicuous. In light of the high prevalence of normal CT examinations for headache, maintaining vigilance when reviewing these studies can be a challenge. An active search pattern may help radiologists to avoid missing subtle but potentially serious diagnoses.

This 2-part series aims to review an approach to imaging patients presenting with severe headaches using a method that mirrors the everyday experience of radiologists. This first part focuses on potentially life-threatening diseases that commonly produce positive findings on the initial NCT. The goal of this article is to facilitate development of an active search pattern for NCT, which is encountered most frequently when evaluating headaches.

Part 2 will discuss diseases that often do not show findings on NCT. Because NCT may appear normal in these patients, these conditions require a heightened level of clinical suspicion to make the diagnosis, as well as a solid knowledge of the strengths and limitations of various imaging techniques. The goal of the second part is to explain how imaging modalities other than NCT may be used to review particular elements of the clinical presentation that may prompt radiologists to suggest such further imaging and make an accurate diagnosis.