ACR Appropriateness Criteria: Headache

Editorial Review

ACR Appropriateness Criteria: Headache

Annette C. Douglas MD, Franz J. Wippold II MD, Daniel F. Broderick MD, et al.

Copyright: 2017 Nilsson et al. (Open access article)

JACO Editorial Reviewer: Cliff Tao, DC, DACBR

Published: June 2018
Journal of the Academy of Chiropractic Orthopedists
June 2018, Volume 15, Issue 2

The original article copyright belongs to the original publisher. This review is available from:

© 2018 Tao and the Academy of Chiropractic Orthopedists. This is an Open Access article which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Author’s Abstract/Introduction:

The cause or type of most headaches can be determined by procuring a careful history and performing a physical examination while focusing on the warning signals that prompt further diagnostic testing. In the absence of worrisome features in the history or examination, the task is then to diagnose the primary headache syndrome based on the clinical features. If atypical features are present or the patient does not respond to conventional therapy, the possibility of a secondary headache disorder should be investigated.

Headache is one of the most frequent ailments of the human race. Studies have estimated overall lifetime prevalence of 0.2%–60% for headache of any kind. In children, prevalence of headache ranges from 8%–83%. As in the case of migraines, characteristics such as age, gender, and case definition may largely account for this variance. However, a higher prevalence of headache has been found by surveys in South America, Europe, and North America than by those of Asian countries. A survey of the Canadian population showed that only about 20% of people there are headache free. Prevalence studies on migraine show that genetic factors are related to prevalence as well as gender differences, as migraines affect approximately 15%–18% of women and 6% of men. Headaches occur most commonly between the ages of 25–55 years. Muscle contraction or tension accounts for most of the non-migraine headaches encountered in population surveys.

Several studies have confirmed the low yield of imaging procedures for individuals presenting with isolated headache, ie, headache unaccompanied by other neurological findings. Patients were referred for imaging because the referring physician suspected imaging-detected pathology or because patients requested the study to be certain that they did not have a brain tumor. A prospective review of 293 computed tomography (CT) scans ordered in an ambulatory family practice setting disclosed that most scans were ordered because the clinician suspected that a tumor (49%) or a subarachnoid hemorrhage (SAH) (9%) might be present. Fifty-nine (17%) were

ordered because of patient expectation or medicolegal concerns.

When considering such a common disorder as headache, indications for imaging use become relevant. This is particularly true in the face of emerging and rapidly evolving technologies in use today. In frequent conditions, performing low-yield studies is more likely to result in false-positive results, with the consequent risk of additional and unnecessary procedures. The yield of positive studies in patients referred with isolated,

nontraumatic headache is approximately 0.4%. Assuming the cost of a CT scan is $400, and a magnetic resonance imaging (MRI) scan is $900, the cost to detect a lesion is $100,000 with CT and $225,000 with MRI.

One should not assume, however, that there is no social benefit in negative imaging studies in the setting of headache. Indeed, headache symptoms can be quite ominous and onerous to those patients, and there can be tremendous costs with respect to productivity and quality-of-life issues. Moreover, health-care providers perceive value in imaging headache when the fear of litigation is taken into account. Although it is beyond the scope of this review to assess the factors and inherent value of negative imaging tests in headache imaging, it must be emphasized that the costs of detection or screening in imaging headache are always overstated when the value of negative results is not factored into the analysis.

JACO Editorial Summary:

  • The American College of Radiology (ACR) is a prominent figure in radiology information and resources, and they have a thorough process for determining the appropriateness of imaging for various conditions.
  • ACR Appropriateness Criteria (ACR AC) are a trademarked, evidence-based set of guidelines to help physicians and other providers in making the most appropriate imaging or treatment decision for specific clinical conditions. ACR AC is the most comprehensive evidence based guidelines for diagnostic imaging, radiotherapy protocols, and image guided interventional procedures.
  • The 15 authors of this article are from the ACR’s Expert Panel on Neurologic Imaging and are all based in the US, and presumably all neuroradiologists. The lead author is Dr. Annette C, Douglas from Indiana University Hospital, in Indianapolis, Indiana.
  • The purpose of this article is to update the reader on the appropriateness of various imaging modalities by specific types of headaches. It was last reviewed in 2013.
  • The search criteria for evidence inclusion and other methodologies were not stated but are available elsewhere. There are 120 references listed, and the paper appears well-referenced.
  • Plain radiography does not appear as an imaging modality, probably because it is not warranted in any of the provided headache types, but probably also because it was not considered.
  • Tension-type headaches and cervicogenic headaches are not included in these guidelines.
  • The following headache types are provided:
    • Chronic headache, no new features and normal neurologic exam
    • Chronic headache, with new feature or neurologic deficit
    • Sudden onset of severe headache or “thunderclap headache”, “worst headache of my life”
    • Sudden onset of unilateral headache, suspected carotid or vertebral artery dissection, or ipsilateral Horner syndrome
    • Headache of trigeminal autonomic origin
    • Headache of skull base, orbital, or perioral region
    • Headache of rhinogenic origin
    • Headache of oral maxillofacial origin
    • New headache in elderly patients with temporal tenderness and elevated ESR
    • New headache in immunosuppressed individuals or cancer patients
    • New headache, suspected meningitis, encephalitis
    • New headache and pregnant women
    • New headache with focal neurologic deficits or papilledema
    • Positional headache
    • Headache associated with cough, exertion, or sexual activity
    • Post-traumatic headache
  • For each headache type, various imaging procedures are rated 1-9 (1-3 = usually not appropriate, 4-6 = may be appropriate 7-9 = usually appropriate), and the relative radiation level provided, along with other comments.
  • For chronic headache with no new features and normal neurologic exam, the only appropriate imaging exams are rated at 4, MRI without and with IV contrast, and MRI head without IV contrast.
  • For chronic headache with new feature or neurologic deficit, the following is provided with rating:
    • MRI head without and with IV contrast: 8
    • MRI head without IV contrast: 7
    • CT head with IV contrast: 7
    • CT head without and with IV contrast: 5
    • MRA head without and with IV contrast: 4
    • MRA head without IV contrast: 4
  • For sudden onset headache or “worst headache of my life”, “thunderclap headache”:
    • CT head without IV contrast: 9
    • CTA head with IV contrast: 8
    • MRA head without and with IV contrast: 7
    • MRA head without IV contrast: 7
    • Arteriography cervicocerebral: 7
    • MRI head without IV contrast: 7
    • MRI head without and with IV contrast: 6
    • CT head without and with IV contrast: 5
  • For sudden onset of unilateral headache or suspected carotid or vertebral dissection or ipsilateral Horner syndrome:
    • CTA head and neck with IV contrast: 8
    • MRA head without IV contrast: 8
    • MRA neck without and with IV contrast: 8
    • MRI head without and with IV contrast: 8
    • MRI head without VI contrast: 8
    • MRA neck without IV contrast: 7
    • CT head without IV contrast: 7
    • MRA head without and with IV contrast: 6
    • Arteriography cervicocerebral: 6
    • CT head without and with IV contrast: 6
    • CT head with IV contrast:: 6
    • MRI neck without IV contrast: 5
    • MRI cervical spine without and with IV contrast: 5
    • MRI cervical spine without IV contrast: 4
    • CT neck with IV contrast: 4
    • CT neck without and with IV contrast: 4


This article is a good up-to-date review to help the chiropractor and the chiropractic orthopedist by suggesting which imaging modality is most appropriate for these types of headaches. The exclusion of tension-type and cervicogenic headaches may suggest that any imaging is probably inappropriate in those clinical settings.