• Headache, or pain over head or face, is a frequent complaint
• Headache is one of the most common types of pain in men, women, children (across all age-groups): >90% of population are affected at some point in the lifetime
• Headache results in significant disability with time loss from school, work and leisure activities
• Many sufferers do not consult their doctors; use of over-the-counter drugs is common
• >300 clinical disorders (IHS - International Headache Society - classification)

Primary headache: (idiopathic)

• Chronic recurrent headaches: can be sub-classified into following 3 groups
• Migraine
• Tension-type headache
• Cluster headache

Secondary headache: associated with organic aetiologies (eg. Brain tumour, stroke/ vascular)

The great majority of patients (70-90%) with headache are suffering from primary headache and can be managed effectively by their family physician

• Features of ominous disease

1. Sudden onset of new, severe headache (SAH, meningoencephalitis)
2. Progressively worsening headache (brain tumour, subdural hematoma, temporal arteritis, other causes of increased ICP)
3. Onset of headache after exertion, straining, coughing or sexual activity (SAH, increased ICP)
4. Changes in cognitive state (eg. Irritable, lethargic)
5. Focal neurological signs (fundoscopy often forgotten, also upgoing Babinski, change in reflexes)
6. Seizures (eg. Brain tumour)
7. Jaw claudication (specific clinical symptom - Giant cell/ temporal arteritis; pain over jaw when chewing; treatable condition)
8. Systemic features such as fever, arthralgia or myalgia
9. Onset of first attack of recurrent headache after the age of 50 years

• Failure in responding to adequate doses of appropriate medication (arbitrary; need to discuss with Pt)
• Possibility of medication abuse and psychological disturbances
• Co-morbidities complicating drug prescription (eg. Psych dis, epilepsy)
• Reassurance of a specialist's opinion

Pain-sensitive structures

• Scalp, skin, periosteum
• Muscles, venous sinuses,
• Meninges,
• Cerebral arteries, nerves
• Brain has no pain fibres (LA to open dura, then can cut brain without any anaesthetic)
• Head pain can occur b/c of pressure, traction, displacement, or inflam of nociceptors
• Ascending serotinergic system
• Descending pain-modulating system

DIAG: neurological innervation for head and facial pain

• CN V1,2,3 -> anterior fossa, middle fossa, facial sensation
• C1,2,3 -> posterior fossa, earline backwards

1. Migraine (eg. 1.1 migraine with aura)
2. Tension-type headache
3. Cluster headache and chronic paroxysmal hemicrania (pain in half of head)
4. Miscellaneous headaches unassociated with structural lesions
5. Headache associated with head trauma
6. Headache associated with vascular disorders
7. Headache associated with non-vascular intracranial disorders
8. Headache associated with substances or their withdrawal
9. Headache associated with non-cephalic infections (pneumonia, infection elsewhere in body)
10. Headache associated with metabolic disorders
11. Headache or facial pain associated with disorders of cranium, neck, eyes, ears, nose, sinuses, teeth, mouth, or other facial or cranial structures
12. Cranial neuralgias, nerve trunk pain, and deafferentation pain
13. Headache not classifiable

Revised classification to be rel next yr

Migraine: no fixed time bet headache, episodic

Tension: same headache over period of time

Cluster: 3-6m period in between headaches

Tumour: progressive increased in headache

• Accurate diagnosis important
• Comprehensive history and physical examination
• History of headache: short/ long, acute/ subacute, progressive/ intermittent/ unilateral
• Associated features: fever, neck stiffness; seizures, focal deficits; aura, family history (migraine often have Fam Hx)
• Physical examination & neurological examination: normal in primary headache, abnormal in secondary headache
• Clinical diagnosis for primary headache
• Investigations to rule out secondary headache like routine laboratory tests: CBC, ESR, basic blood biochemistry, endocrine tests, urinalysis, urine and blood for toxicology
• Additional diagnostic tests: (these cannot make Dx of primary headache, usu for Dx of secondary headache)

1. CT or MRI (CT may not be able to exclude demyelinating disease like MS, MRI normal can almost be positive that no disease causing secondary headache)
2. LP and CSF analysis
3. EEG, ECG
4. Cervical spine X-ray (headache caused by cervical spondylosis)
5. Arteriography and MRA (if abn CT/ MRI showing possibility of vascular malformation)
6. USG (incl intracranial US)
7. Evoked potential (lesion affecting corticospinal tract)
8. Test of temperomandibular joint (dysfunction causing headache)
9. Dental evaluation
10. Ear, nose and throat evaluation (esp. NPC, v common in our locality)

• Preventive (prophylactic) therapy: current/ recurrent frequent prob causing interference with daily activities (arbitrary, if Pt thinks headache causes disability)
• Symptomatic (acute/abortive) therapy: varies b/c pain threshold varies among ppl, t/f also need to discuss with Pt (visual analogue scale, VAS, scale 0-10, can be used for follow-up on Tx effectiveness)
• Visual analogue scale
• Lines exactly 100mm long
• No pain (0) - Excruciating pain (100): Pt to tell how painful it is
• Complete pain relief (0) - No pain relief (100): Dr to document how well Tx is working

• Treatment or prevention
• Non-pharmacological: avoidance of trigger (modify lifestyle)

• Examples: meningitis, encephalitis, brain abscess, subdural haematoma, stroke, brain tumour, temporal arteritis, migraine, tension-type headache, cluster headache, trigeminal neuralgia, NPC, glaucoma

(In order of prevalence)

• Commonest form of headache
• Diffuse, dull, aching, "band-like"
• Worse on touching the scalp, Aggravated by noise
• Associated with "tension"
• But not with physical symptoms
• Hours to days
• Infrequent or daily, worse towards the end of the day
• Can persist over many years
• Types

1. Episodic tension-type headache

1. Episodic tension-type headache associated with disorder of pericranial m's
2. Episodic tension-type headaches unassociated with disorder of pericranial m's

1. Chronic tension-type headache

• Mx

1. Mechanism: muscular due to persistent contraction
2. Reassurance (eg. Pt's headache may disappear if CT/MRI normal, t/f imp)
3. Attempt to reduce psychological stress (any emotional, psychosocial probs)
4. Benzodiazepines (short course)
5. Antidepressants
6. Simple analgesics: Panadol, NSAIDs

• Onset: Childhood or early adulthood
• Incidence: 5 - 10% of population
• Female to male ratio: 2:1
• Family history: 70% of all sufferers (less common in HK cf. Western countries, b/c whole detailed Fam Hx may not be obtainable from Pt him/herself)
• Characteristic: (1) Paroxysmal headache, 4 - 48 hrs (2) Freq: rarely occur >2x/w (3) Unilat throbbing headache
• Phases of migraine: prodrome; aura; headache
• Types

1. Migraine without aura (common migraine - old term, don't use anymore in new classification)
2. Migraine with aura

• Provoking factors

1. Hormonal (menstruation, OCP)
2. Emotional, personal or behavioural; stress; sleep deprivation; minor head injury)
3. Dietary (alcohol, chocolate, cheese - thiamine)
4. Others

• Aggravate by bright light
• Relieved by sleep
• Assoc. w/ nausea and vomiting
• Mechanism: 5 Hydroxytryptamine and NE
• Prophylaxis

1. Propranolol (beta blocker) - most common (non-cardiac selecting beta-blocker, relatively safe, relative lack of S/E, sometimes tiredness, men c/o impotence, dizziness due to hT)
2. Pizotifen, Methysergide (5HT₂-receptor blocker, retroperitoneal fibrosis, t/f relatively seldom use these days)
3. Anticonvulsants (VPA, PHT, GBP, other anticonvulsants)
4. TCA, Ca channel blockers (esp. veripramil)

• Acute attack

1. Simple analgesic (paracetamol), anti-emetic (metoclopramide) (if analgesic alone, Pt may vomit up t/f absorption prob)
2. Sumatriptan (selective 5-HT₁ blocker; "triptan", 8 types; formerly considered to be migraine-specific, but now known to be effective in non-migraine conditions)
3. Ergotamine (non-selective 5HT receptor blocker, S/E: vascular problem: peripheral gangrene, uncommon)
4. Methylprednisolone (for status migrainous - continuous migraine)

• Rare subtypes

1. Basilar migraine: basilar artery system (hemi/tetraparesis, dysarthria)
2. Hemiplegic migraine
3. Ophthalmoplegics migraine (usu. CN III, rarely VI); paralysed extraocular movt
4. Migraine coma (very rare): coma always need to exclude other more common causes than migraine

• Man > woman
• Onset in middle age
• Unilateral pain around one eye
• Assoc. with conjunctival injection, lacrimation, rhinorrhoea, occ. transient Horner's syndrome (locally autonomic system over eye region)
• 10min - 2h
• Once to many times per day, waking up from sleep
• Clusters separate by weeks or months
• Mechanism: histamine level increase during attack
• Treatment

1. Antihistamine: poor result
2. Simple analgesic
3. Ergotamine: effective
4. Sumatriptan: effective
5. Prednisolone: 30mg qd (short-course steroids for 1w, stop once headache subsides)

• Prophylaxis

1. Methysergide (toxic)
2. Ca channel blockers
3. Lithium

• Symptoms of disease inv. intracranial or extracranial structures or of metabolic disturbance; 3 temporal patterns
• 3 temporal patterns

1. Severe, sudden-onset headache
2. Acute/subacute, intermittent, recurrent headache
3. Subacute, persistent, progressive headache

• SAH
• Brain haemorrhage
• Acute subdural or epidural hematoma
• Acute severe HT
• Acute glaucoma
• Internal carotid dissection or other acute carotid syndromes
• Acute hydrocephalus
• Head trauma

• Encephalitis or meningitis
• Sphenoid sinusitis or periorbital cellulitis
• Optic neuritis
• Cerebral vasculitis
• Cerebral vein thrombosis
• ischaemic cerebrovascular disease
• CSF hypotension (very rare, phaeochromocytoma)
• Obstructive hydrocephalus
• Phaeochromocytoma

• Chronic subdural hematoma
• Brain tumour
• Brain abscess
• Cerebral vein thrombosis
• Idiopathic intracranial hypertension
• Central nervous system infection
• Temporal and cerebral arteritis progressive metabolic abnormalities
• Headache associated with substances or their withdrawal
• Cervical spine, occipito-cervical junction disease
• Dental, cranial vault, eromandibular joint syndrome
• Cranial, paranasal, sphenoid sinusitis
• Local infiltration by tumour (NPC),
• High blood pressure

• An autoimmune disease
• Presents with headaches in ELDERLY
• Severe, throbbing, intractable (intractable to treatment)
• Thickened, tender, nonpulsatile temporal artery (important in elderly Pt examination)
• Jaw claudication and visual symptom (blindness)
• Stroke, hearing loss, myelopathy, neuropathy
• Systemic features: wt loss, lassitude, general myalgia
• Mechanism: Giant cell infiltration of large and medium-size arteries
• Dx

1. High ESR, CRP
2. Anaemia, thrombocytosis (increased platelets)
3. TA (temporal artery) biopsy (skipped lesion - therefore cannot exclude GCA even with negative biopsy)

• Treatment

1. Prednisolone 60mg qd (URGENT Tx - if not, Pt may become blind)
2. Monitor ESR (for Tx response)

1. Nerve root compression (Vascular loop inside BS touching trigeminal nerve, CP angle tumour)
2. Demyelination: young Pt (eg. 30yo female; must rule out demyelination attacking BS)

• Treatment

1. Carbamazepine (can be stopped after remission)
2. TCA (eg. Amytriptylline)
3. Baclofen
4. Other AEDs (LMT, PHT) (anti-epileptic drugs)
5. Surgical (intractable case, no response to Tx, separate vascular loop touching trigeminal n, endoscopic procedure)

• Follows activation of a latent varicella zoster infection (harboured in dorsal root ganglion)
• Usu 1w after healing of infection
• Burning, constant pain with severe paroxysmal twinges
• Touch exacerbate the pain
• Look for herpes scar, pain over that particular dermatome
• Tx: CBZ (carbazebmide), TCA, sometimes surgical resection of nerve root