Editing Headache (section)

=== Neuroimaging ===

==== Old headaches ====
The US Headache Consortium has guidelines for neuroimaging of non-acute headaches.<ref>{{cite book | vauthors = Frishberg BM, Rosenberg JH, Matchar DB, McCrory DC, Pietrzak MP, Rozen TD, Silberstein SD | title = Evidence-based guidelines in the primary care setting: neuroimaging in patients with nonacute headache. | location = St Paul, MN | publisher = US Headache Consortium | date = April 2000 | pages = 1–25 | citeseerx = 10.1.1.565.1524 }}</ref> Most old, chronic headaches do not require neuroimaging. If a person has the characteristic symptoms of a migraine, neuroimaging is not needed as it is very unlikely the person has an intracranial abnormality.<ref name="AHSfive">{{cite web |author1=American Headache Society |author1-link=American Headache Society |date=September 2013 |title=Five Things Physicians and Patients Should Question |publisher=[[American Headache Society]] |work=[[Choosing Wisely]] |url=http://www.choosingwisely.org/doctor-patient-lists/american-headache-society/ |access-date=10 December 2013 |url-status=dead |archive-url=https://web.archive.org/web/20131206060123/http://www.choosingwisely.org/doctor-patient-lists/american-headache-society/ |archive-date=6 December 2013 }}, which cites
* {{cite journal | vauthors = Lewis DW, Dorbad D | title = The utility of neuroimaging in the evaluation of children with migraine or chronic daily headache who have normal neurological examinations | journal = Headache | volume = 40 | issue = 8 | pages = 629–632 | date = September 2000 | pmid = 10971658 | doi = 10.1046/j.1526-4610.2000.040008629.x | s2cid = 14443890 }}
* {{cite journal | vauthors = Silberstein SD | title = Practice parameter: evidence-based guidelines for migraine headache (an evidence-based review): report of the Quality Standards Subcommittee of the American Academy of Neurology | journal = Neurology | volume = 55 | issue = 6 | pages = 754–762 | date = September 2000 | pmid = 10993991 | doi = 10.1212/WNL.55.6.754 | doi-access = free }}
* {{cite journal | author = Medical Advisory Secretariat | title = Neuroimaging for the evaluation of chronic headaches: an evidence-based analysis | journal = Ontario Health Technology Assessment Series | volume = 10 | issue = 26 | pages = 1–57 | year = 2010 | pmid = 23074404 | pmc = 3377587 }}</ref> If the person has neurological findings, such as weakness, on exam, neuroimaging may be considered.{{citation needed|date=June 2021}}

==== New headaches ====
All people who present with [[#Red flags|red flags]] indicating a dangerous secondary headache should receive neuroimaging.<ref name=Hainer /> The best form of neuroimaging for these headaches is controversial.<ref name=Clinch /> Non-contrast computerized tomography (CT) scan is usually the first step in head imaging as it is readily available in Emergency Departments and hospitals and is cheaper than MRI. Non-contrast CT is best for identifying an acute head bleed. Magnetic Resonance Imaging (MRI) is best for brain tumors and [[Posterior fossa malformations–hemangiomas–arterial anomalies–cardiac defects–eye abnormalities–sternal cleft and supraumbilical raphe syndrome|problems in the posterior fossa]], or back of the brain.<ref name=Clinch /> MRI is more sensitive for identifying intracranial problems, however it can pick up brain abnormalities that are not relevant to the person's headaches.<ref name=Clinch />

The American College of Radiology recommends the following imaging tests for different specific situations:<ref name="Strain_2000">{{cite journal | vauthors = Strain JD, Strife JL, Kushner DC, Babcock DS, Cohen HL, Gelfand MJ, Hernandez RJ, McAlister WH, Parker BR, Royal SA, Slovis TL, Smith WL, Rothner AD | title = Headache. American College of Radiology. ACR Appropriateness Criteria | journal = Radiology | volume = 215 | issue = Suppl | pages = 855–60 | date = June 2000 | pmid = 11037510 | doi = | url = }}</ref>

{|class="wikitable"
|-
! Clinical Features !! Recommended neuroimaging test
|-
| Headache in immunocompromised people (cancer, HIV) || [[MRI]] of head with or without contrast
|-
| Headache in people older than 60 with suspected temporal arteritis || MRI of head with or without contrast
|-
| Headache with suspected meningitis || CT or MRI without contrast
|-
| Severe headache in pregnancy || CT or MRI without contrast
|-
| Severe unilateral headache caused by possible dissection of carotid or arterial arteries || MRI of head with or without contrast, [[magnetic resonance angiography]] or [[Computed tomography angiography|Computed Tomography Angiography]] of head and neck.
|-
| Sudden onset headache or worst headache of life || CT of head without contrast, [[Computed tomography angiography|Computed Tomography Angiography]] of head and neck with contrast, [[magnetic resonance angiography]] of head and neck with and without contrast, MRI of head without contrast
|}

==== Lumbar puncture ====
A [[lumbar puncture]] is a procedure in which cerebral spinal fluid is removed from the spine with a needle. A lumbar puncture is necessary to look for infection or blood in the spinal fluid. A lumbar puncture can also evaluate the pressure in the spinal column, which can be useful for people with [[idiopathic intracranial hypertension]] (usually young, obese women who have increased intracranial pressure), or other causes of increased intracranial pressure. In most cases, a CT scan should be done first.<ref name=Goadsby />