🔴 Q3  ·  20 Marks  ·  Red Theme

Migraine vs Subarachnoid Haemorrhage

Gradual vs Sudden — Know the difference. It saves lives.

Exam Question: Discuss the presentation of migraines. Explain how they differ from severe headaches such as acute headaches and subarachnoid headaches.

S1Classification
2 marks
S2Migraine Epidemiology
3 marks
S3Migraine Presentation
4 marks
S4SAH Definition
4 marks
S5Comparison Table
3 marks
S6Other Severe Headaches
2 marks
S7Chronic Contrast
1 mark
+Osteo Safety
+ Red Flags

⚡ Memory Hooks

🌀 MIGRAINE

Gradual · Episodic · Dark Room
Builds slowly over minutes–hours
Episodic — not continuous
Photophobia → needs dark room
Aura ≤ 30 min then headache

💥 SAH

Sudden · Explosive · Hospital NOW
Thunderclap — worst ever in seconds
"Sledgehammer to back of neck"
Neck stiffness + meningism
Emergency CT → LP if CT negative
Section 1

Headache Classification

2 marks

Headaches are classified into five broad categories (ICOM Headaches ppt):

TYPE 1
Vascular
Migraine, Cluster
TYPE 2
Tension / Cervicogenic
Tension-type, Cervical origin
TYPE 3
Pressure / Inflammatory
Sinusitis, Raised ICP
TYPE 4
Cranial Neuralgias
Trigeminal neuralgia, TMJ
TYPE 5
Psychogenic
Anxiety, Depression

📚 Reference: ICOM Headaches ppt, Year 4 Google Classroom

Section 2

Migraine — Definition & Epidemiology

3 marks
  • Prevalence: Affects up to 2% of the population
  • Sex: F > M (hormonal influence — oestrogen fluctuation)
  • Nature: Episodic — distinct from continuous tension headache
  • Onset: Typically adolescence to early adulthood; may improve post-menopause

Two Main Types

TypeAlso Known AsKey Feature
Migraine with auraClassic migraineNeurological aura precedes headache (visual, sensory, motor)
Migraine without auraCommon migraineNo aura; more frequent type; diagnosis of exclusion

📚 Reference: ICOM Headaches ppt; ICHD-3 Classification 2018

Section 3

Migraine — Clinical Presentation

4 marks

Onset & Character

  • Gradual build over minutes to hours — unilateral or generalised
  • Severe throbbing / pulsating quality
  • Nausea, vomiting, photophobia, phonophobia
  • Unable to continue normal activities — patient seeks dark quiet room
  • Duration: hours to a day (4–72 hours per ICHD-3)

⚡ Aura (Classic Migraine): Flashing coloured lights (scintillating scotoma), zigzag lines, visual field defects, sensory tingling, or motor weakness. Aura lasts no longer than 30 minutes and fully resolves before or with headache onset.

Common Triggers

🍫 Chocolate 🧀 Cheese 🍷 Wine / Alcohol 🥛 Dairy ☕ Coffee / Tea 😴 Sleep disruption 💊 Hormonal changes 😰 Stress 💡 Bright lights 🌬️ Strong smells

📚 Reference: ICOM Headaches ppt; ICHD-3 Classification 2018; Kumar & Clark 10th ed

Section 4

Subarachnoid Haemorrhage (SAH) — Definition & Presentation

4 marks

Presentation

  • Sudden onset — patient describes as "like a blow to the head" or "sledgehammer to the back of the neck"
  • Thunderclap headache — worst ever headache, maximal intensity within seconds
  • Nausea, vomiting, photophobia
  • Neck stiffness — meningism from blood in subarachnoid space
  • Headache becomes generalised
  • Possible loss of consciousness
  • Focal neurological signs: dysphasia, hemiparesis

Cause

  • Berry aneurysm rupture in the Circle of Willis (most common)
  • Arteriovenous malformation (AVM)
  • Rebleeds are commonly fatal — urgent neurosurgical intervention required

Investigations

1

CT brain scan — first-line for all suspected SAH; detects blood in subarachnoid space

2

10% of SAH have negative CT — do not exclude SAH on negative CT alone

3

Lumbar puncture — at least 8–12 hours after onset to detect xanthochromia (yellow CSF from haemoglobin breakdown)

📚 Reference: ICOM Headaches ppt; ICOM Vascular and Neurology ppt; NICE CKS Headache 2023

Section 5

Migraine vs SAH — Comparison Table

3 marks
Feature Migraine SAH
Onset Gradual (minutes–hours) Sudden (seconds — thunderclap)
Character Throbbing, pulsating Explosive — "worst ever"
Aura Possible (≤30 min, reversible) None
Neck stiffness No Yes — meningism
Neurological signs Aura only — fully reversible Dysphasia, hemiparesis
Loss of consciousness No Possible
Photophobia Yes — seeks dark room Yes — but with meningism
Duration Hours to a day Persistent / progressive
Nausea/Vomiting Common Common
Triggers Food, hormones, stress Exertion, straining
Immediate action Dark room, analgesia, antiemetics Emergency CT → LP → neurosurgery

📚 Reference: ICOM Headaches ppt; ICOM Vascular and Neurology ppt

Section 6

Other Severe Headaches to Distinguish

2 marks

Raised Intracranial Pressure (ICP)

  • Worse in the morning — wakes patient from sleep
  • Nausea and effortless vomiting (not preceded by nausea)
  • Not relieved by analgesics
  • Aggravated by coughing, sneezing, bending forward
  • Transient visual disturbance (papilloedema)
  • Progressive worsening over days to weeks

Temporal Arteritis (Giant Cell Arteritis)

  • Age >55 — new headache in this age group must be investigated
  • Malaise, aches, weight loss, low-grade fever
  • Scalp tenderness — pain on pillow or brushing hair
  • Redness and tenderness over temporal artery
  • Jaw claudication — pain on chewing
  • Risk of blindness — anterior ischaemic optic neuropathy
  • Investigations: ESR markedly raised, temporal artery biopsy
  • Treatment: Steroids immediately — do not wait for biopsy result

📚 Reference: ICOM Headaches ppt; Kumar & Clark Clinical Medicine 10th ed

Section 7

Chronic Headache — Tension-Type Contrast

1 mark
  • Tension headache: Bilateral pressure / band-like sensation around head
  • No nausea, no visual disturbance, no photophobia
  • Builds through the day — worse with stress and posture
  • Not aggravated by physical activity (unlike migraine)
  • Analgesic overuse headache: Rebound headache from frequent analgesic use (>10–15 days/month) — must be considered in chronic daily headache

📚 Reference: ICOM Headaches ppt; NICE CKS Headache 2023

🦴 Osteopathic Safety — Cervical Treatment & Headaches

VBI Screen before any cervical treatment:

  • Diplopia (double vision)
  • Dizziness / vertigo
  • Dysarthria (slurred speech)
  • Dysphagia (difficulty swallowing)
  • Drop attacks (sudden falls without LOC)

Absolute contraindications to cervical HVLA:

  • Thunderclap headache — do NOT treat; refer as emergency
  • Suspected or confirmed SAH
  • Raised intracranial pressure
  • Cervical instability (RA atlantoaxial, trauma)
  • New or changing headache pattern — investigate before manipulation

📚 Reference: ICOM Cervical and Thoracic Spine Assessment; ICOM Manipulation Notes Summary

🚨 Red Flags — Refer Immediately

  • Thunderclap onset — maximal intensity within seconds
  • Worst ever headache — patient's own description
  • Fever + neck stiffness + altered consciousness (meningitis / SAH)
  • Focal neurological deficit (dysphasia, hemiparesis, diplopia)
  • Progressive worsening headache over days/weeks (raised ICP)
  • Morning headache waking from sleep with effortless vomiting
  • New headache in patient over 50
  • Jaw claudication + scalp tenderness (temporal arteritis — risk of blindness)
  • Headache following head trauma
  • Headache in immunocompromised or cancer patient

📖 References

  1. ICOM Headaches ppt, Year 4 Google Classroom
  2. ICOM Vascular and Neurology ppt, Year 4 Google Classroom
  3. ICOM Cervical and Thoracic Spine Assessment, Year 4 Google Classroom
  4. ICOM Manipulation Notes Summary, Year 4 Google Classroom
  5. NICE CKS Headache (2023). Available at: cks.nice.org.uk
  6. International Headache Society. ICHD-3 Classification of Headache Disorders, 3rd ed. Cephalalgia. 2018;38(1):1–211.
  7. Kumar P, Clark M. Kumar & Clark's Clinical Medicine, 10th ed. Elsevier; 2021.