What tests are used to diagnose migraines?

Diagnostic Tests for Migraines

Migraine diagnosis is primarily based on clinical criteria and medical history, with no specific laboratory or imaging tests required for routine diagnosis. 1, 2

Medical History Assessment

The cornerstone of migraine diagnosis involves collecting a comprehensive medical history that includes:

• Age at onset of headache 1
• Duration of headache episodes (typically 4-72 hours for migraine) 2
• Frequency of headache episodes 1
• Pain characteristics:
  • Location (often unilateral) 1, 2
  • Quality (typically pulsating) 1, 2
  • Severity (moderate to severe) 1, 2
  • Aggravating factors (e.g., physical activity) 1
  • Relieving factors 1
• Accompanying symptoms:
  • Photophobia (sensitivity to light) 1, 2
  • Phonophobia (sensitivity to sound) 1, 2
  • Nausea and/or vomiting 1, 2
• Aura symptoms, if present 1
• History of acute and preventive medication use 1
• Family history of migraine 1

Diagnostic Criteria

The International Headache Society's ICHD-3 criteria are used to establish the diagnosis of migraine:

• For migraine without aura: at least five attacks fulfilling specific criteria including headache duration of 4-72 hours, specific pain characteristics, and associated symptoms 2
• For migraine with aura: at least two attacks with fully reversible aura symptoms 2
• For chronic migraine: headache on ≥15 days/month for >3 months, with migraine features on ≥8 days/month 1, 2

Diagnostic Aids

Several tools can assist in the diagnostic process:

• Headache diaries: Record pattern and frequency of headaches, accompanying symptoms, and medication use 1
• Headache calendars: Track temporal occurrence of headaches and related events (e.g., menstruation) 1
• Screening questionnaires:
  • Three-item ID-Migraine questionnaire: Assesses headache-associated nausea, photophobia, and disability (sensitivity 0.81, specificity 0.75) 1
  • Migraine Screen Questionnaire (MS-Q): Five questions about headache frequency, intensity, duration, associated symptoms, and disability (sensitivity 0.93, specificity 0.81) 1

Physical Examination

• A thorough neurological examination is typically performed to rule out secondary causes 1
• Physical examination is usually normal in patients with migraine 3, 4

When Further Testing Is Needed

Further investigations are generally not required for typical migraine presentations but may be considered when:

• "Red flags" are present in the history or examination 3
• Atypical features are present 3, 5
• Secondary headache disorders are suspected 1, 3

When indicated, these may include:

• Neuroimaging (MRI or CT): To rule out structural causes 3, 5
• Blood tests: To exclude systemic conditions 3
• Lumbar puncture: When meningitis or increased intracranial pressure is suspected 3, 4

Common Pitfalls in Migraine Diagnosis

• Overreliance on imaging studies when clinical presentation is typical for migraine 5
• Failure to recognize medication overuse headache, which requires assessment of acute medication use patterns 1
• Misdiagnosis as tension-type headache, which typically involves bilateral, mild to moderate pain with pressing quality 1
• Delayed diagnosis, often exceeding one year from symptom onset, leading to unnecessary investigations 5

Differential Diagnosis

Migraine must be distinguished from:

• Other primary headache disorders (tension-type headache, cluster headache) 1, 6
• Secondary headache disorders (those caused by underlying pathology) 1, 3