Indications for Head Imaging in Patients with Migraines

Primary Indications for Neuroimaging

The American Academy of Family Physicians recommends that neuroimaging should be considered in patients with migraine who have an unexplained abnormal finding on neurological examination, as this significantly increases the likelihood of identifying intracranial pathology 1, 2
Abnormal neurological examination findings increase the likelihood of intracranial pathology such as brain tumors, arteriovenous malformations, and hydrocephalus 1, 3
Thunderclap headache, which may indicate subarachnoid hemorrhage, is a primary indication for neuroimaging 4
Headache described as "worst headache of life" suggests possible serious vascular pathology and warrants neuroimaging 4
New-onset headache in patients over age 50 raises suspicion for secondary headache including temporal arteritis and requires neuroimaging 4
Progressive headache that worsens over time potentially indicates an intracranial space-occupying lesion and necessitates neuroimaging 4
Headache aggravated by Valsalva maneuver may suggest increased intracranial pressure and is an indication for neuroimaging 1, 5, 4
Headache that awakens the patient from sleep possibly indicates increased intracranial pressure and warrants neuroimaging 1, 4
Marked change in previously stable headache pattern is a primary indication for neuroimaging 4
Headache associated with focal neurological symptoms or signs requires neuroimaging 4
Persistent headache following head trauma is an indication for neuroimaging 4

Unexplained fever may indicate meningitis and is a secondary indication for neuroimaging 4
Neck stiffness is a possible indicator of meningitis or subarachnoid hemorrhage and warrants neuroimaging 4
Weight loss associated with headache suggests possible malignancy and requires neuroimaging 4
Impaired memory, altered consciousness, or personality changes are secondary indications for neuroimaging 4
Uncoordination potentially indicates cerebellar pathology and is a secondary indication for neuroimaging 4

Patients with migraine and normal neurological examination have a low prevalence of significant intracranial abnormalities (approximately 0.2%) and do not typically require neuroimaging 1, 6, 3
Patients with typical features of migraine who meet the strict definition of migraine do not typically require neuroimaging 1, 2
Patients with tension-type headache and normal neurological examination may not require neuroimaging, though evidence is limited 7, 6

No definitive recommendations exist regarding the comparative sensitivity of MRI versus CT for migraine evaluation, according to the American Academy of Family Physicians 1, 2
MRI may be more sensitive than CT in identifying clinically insignificant abnormalities but not necessarily more sensitive for clinically significant pathology, as suggested by the American Academy of Family Physicians 3, 5
MRI is generally preferred due to higher resolution and absence of radiation exposure, except when acute intracranial hemorrhage is suspected, where CT without contrast is recommended, as stated by the American College of Radiology 4

The prevalence of significant intracranial abnormalities in patients with migraine and normal neurological examination is approximately 0.2%, similar to the rate in asymptomatic volunteers (0.4%), according to the American Academy of Neurology 6
Testing should be avoided if it will not lead to a change in management, as recommended by the American Academy of Family Physicians 3
Testing is not recommended if the patient is not significantly more likely than the general population to have a significant abnormality, according to the American College of Physicians 3
False positive findings are more likely than true positive ones when pre-test probability is low, potentially leading to unnecessary concerns, further investigations, and procedures, as stated by the American College of Radiology 8

Overlooking the need for neuroimaging when red flags are present is a common pitfall, as warned by the American College of Emergency Physicians 4
Overutilization of imaging in patients with typical migraine features and normal neurological examinations is a common pitfall, according to the American Academy of Family Physicians 1, 3
Failure to recognize that certain features (headache worsened by Valsalva maneuver, headache awakening patient from sleep, new-onset headache in older patients) increase likelihood of significant intracranial pathology is a common pitfall, as noted by the American Academy of Neurology 1, 2
Not considering that imaging may occasionally be warranted in individual cases where patients are excessively worried about serious underlying causes, even when not clinically indicated, is a common pitfall, as stated by the American Academy of Family Physicians 1, 3