Headache & Migraine Localizer
Read the pattern before you name the headache
Headache is the highest-volume complaint in neurology. The question is never just how bad the pain is - it is whether the timing, quality, and associated features point toward a primary headache disorder or toward a red flag that changes everything.
Headache presets
Read the history, then rank the differential
Primary headache and red-flag recognition
Syndrome frame
Migraine with aura
Cortical spreading depression with fully reversible neurological aura
Unilateral throbbing headache preceded by a gradually evolving visual aura, typically scintillating scotoma or expanding fortification spectra, followed by photophobia, phonophobia, and nausea.
Strongest localization
Occipital/visual cortex spreading depression producing a gradually marching positive visual phenomenon, not a fixed structural lesion.
The aura's gradual march (5-60 minutes) and positive symptoms (scintillations, zigzag lines), not a sudden negative deficit, is what separates it from TIA.
History discriminators
- • Aura duration 5 to 60 minutes with gradual march across the visual field
- • Positive visual phenomena (scintillations, fortification spectra) rather than a sudden field cut
- • Headache begins during or within 60 minutes of aura resolution
- • Personal or family history of similar stereotyped episodes
Mechanism
Cortical spreading depression - a slow wave of neuronal and glial depolarization followed by suppression - propagates across the cortex (classically occipital, producing visual aura) and is thought to activate trigeminovascular afferents, producing the headache phase.
Bedside tasks
Aura timeline
Symptoms build gradually over 5 to 60 minutes rather than appearing instantly.
A gradual march is reassuring against an acute vascular event; a sudden-onset deficit should redirect toward TIA/stroke workup.
Visual phenomenology
Scintillating scotoma or fortification spectra spreading across the visual field.
Positive visual phenomena are typical of cortical spreading depression, not of an ischemic negative field cut.
Headache-aura relationship
Headache follows the aura, usually within an hour.
An aura without any subsequent headache still counts as migraine aura but should prompt closer scrutiny if this is a first episode.
Teaching pearl
A gradually marching, fully reversible positive visual phenomenon followed by headache is migraine aura until proven otherwise - but a first-ever aura after age 50, or a deficit that doesn't fully reverse, should be treated as a red flag.
Red flag score
lowTypical duration
4 to 72 hours untreated
Compare mode
Best fit versus attractive wrong turn
Best fit: Migraine with aura
Red flag score
lowTypical duration
4 to 72 hours untreated
Compare to: Migraine without aura
Red flag score
lowTypical duration
4 to 72 hours untreated
Why the selected preset beats this alternative
TIA becomes weaker when the deficit evolves gradually with positive visual phenomena rather than an abrupt negative visual field cut, and when headache and photophobia follow the aura.
Case Mode
Practice headache localization before the reveal
Treat these like consult questions. Decide whether the history points toward migraine with or without aura, tension-type, cluster, or a secondary red flag before you reveal the answer.
Study progress
Track your case accuracy inside this module
Cases completed
0/ 3
Correct reveals
0
Accuracy
0%
Training stage
Primary headache and red-flag recognition
Advanced objectives
- • Distinguish migraine aura from TIA using onset speed, symptom polarity (positive vs negative), and full reversibility.
- • Recognize the ipsilateral autonomic signs and restless behavior that separate cluster headache from migraine.
- • Treat time-to-maximal-intensity, not pain severity alone, as the decisive discriminator for thunderclap headache.
Clinical vignette
Sudden 'worst headache of my life' during exertion
A 44-year-old develops instantaneous, maximal-intensity headache while lifting weights, with neck stiffness on exam.
Chief complaint
It felt like someone hit me in the back of the head. It was the worst pain I've ever had, and it was full-blown within seconds.
History
Onset during a heavy deadlift. Pain reached maximal intensity almost immediately. Brief loss of awareness reported by a gym partner. No prior history of similar headaches. No fever.
Syndrome frame
Thunderclap onset (seconds to maximal intensity) plus exertional trigger plus transient loss of awareness is the classic subarachnoid hemorrhage presentation until proven otherwise - this pattern, not the pain severity alone, is what demands urgent neuroimaging and, if CT is negative, further workup.
Exam findings
- • Neck stiffness (nuchal rigidity) on exam
- • Photophobia
- • No focal motor or sensory deficit
- • Alert but appears distressed
- • Blood pressure mildly elevated
Prompt
Why does the speed of onset matter more than the severity of pain here, and what does the exertional trigger add to your concern?
- Compare time-to-maximal-intensity here with how migraine or tension-type headaches typically build.
- Think about what structural event an exertional/Valsalva trigger with sudden severe head pain classically produces.
Localization cues
- • Seconds-to-maximal-intensity onset points to a vascular/structural event, not a primary headache disorder.
- • Nuchal rigidity suggests meningeal irritation, consistent with subarachnoid blood.
Differential traps
- • Do not label this 'a bad migraine' because the patient has had headaches before - the onset pattern here is categorically different from a prior stereotyped pattern.
- • A normal neurologic exam does not exclude subarachnoid hemorrhage; the onset pattern alone is enough to mandate urgent imaging.
Next data to request
- • Non-contrast CT head immediately
- • If CT negative and clinical suspicion remains, lumbar puncture (looking for xanthochromia) or CT angiography per local protocol
- • Blood pressure management and neurosurgical consultation if hemorrhage confirmed
Working pattern selection
Current pick: Migraine without aura
Reading rules
Four rules that prevent most headache localization errors
Rule 1
Time-to-maximal-intensity separates thunderclap headache from every primary headache disorder - seconds to a minute is the threshold that matters, not pain severity alone.
Rule 2
Unilateral throbbing plus activity worsening plus nausea or photophobia/phonophobia is migraine; bilateral pressing without those features is tension-type.
Rule 3
Ipsilateral autonomic signs plus restlessness during a brief, severe, strictly unilateral attack is cluster headache, not migraine.
Rule 4
A first-ever aura, a headache that has changed in character, or any new focal deficit deserves red-flag screening before a benign label is applied.
Module handoff
Where to go next
Brain Atlas
Post-clinical anatomical convergence
Vertigo & Vestibular Localizer
Bedside vestibular localization
Sleep Architecture
Clinical sleep medicine fundamentals
Neuro Tutor
Cross-module consult reasoning with explicit scoring