headache/migraine Flashcards
pathophysiology of headache
- vasodilation of intracranial cerebrovascular blood vessel -> activation of perivascular trigeminal nerves -> release vasoactive neuropeptides -> promote neurogenic inflammation
- central pain transmission activate other brainstem nuclei -> associated symptoms
- hyperresponsiveness of brain
** inherited abnormality in Ca or Na channel & Na/K pumps that regulate cortical excitability through release of serotonin and other neurotransmitters
** increased levels of excitatory amino acids (glutamate), alteration in level of extracellular K affect migraine threshold
action of serotonin in terms of headache pathophysiology
- agonist of vascular and neuronal 5-HT1 receptor subtype
- cause vasoconstriction of meningeal blood vessels and inhibition of vasoactive neuropeptide release and pain signal transmission
ICHD-3 classifications of headaches
1) primary
- migraine
- tension type headache (TTH)
- other primary HA disorders
2) Secondary
- trauma/injury to head and/or neck
- cranial/cervical vascular disorder
- non-vascular intracranial disorder
- infection
- homeostasis disorder
- HA/facial pain attributed to disorder of cranium, neck, eyes, ears, sinus, teeth, mouth, other facial/cervical structures
- psychiatric disorder
3) neuropathies, facial pain, other headache
red flags for secondary headache (SNNOOP10)
1) systemic symptoms including fever
2) neoplasm in history
3) neurologic deficit/dysfunction
4) onset of headache sudden/abrupt
5) older age (>50)
6) pattern change/recent onset of headache
7) positional headache
8) precipitated by sneezing, coughing, exercise
9) papilledema
10) progressive headache with atypical presentation
11) pregnancy or puerperium
12) painful eye with autonomic features
13) post-traumatic onset of headache
14) pathology of immune system (HIV/immunocompromised)
15) painkiller overuse/new drug at onset of headache
primary headache - cluster headache
- unilateral (around eye or along face)
- variable pain quality
- severe - very severe pain intensity
- restlessness, agitation
- cranial autonomic symptoms in same side of headache
** red, water, or swollen eye
** nasal congestion/runny nose, sweating - 15 - 180 mins
epidemiology of TTH
- peak in 4th decade
- female > male
classifications of TTH
- infrequent: < 1 ep per month
- frequent: 1 - 14 days per month
- chronic: ≥ 15 days per month
TTH triggers
1) physical/emotional stress
2) activities that cause head to be held in one position for long time
3) alcohol, caffeine
4) cold/flu or sinus infection
5) dehydration, hunger
goal of TTH management
relief pain, prevent progression to chronic
TTH pharmacological
1) acute
- paracetamol (+/- caffeine), aspirin
- NSAID: ibuprofen, naproxen, diclofenac, ketoprofen
2) prophylactic
- 1st line: amitriptyline
- mirtazapine, venlafaxine
TTH nonpharmacological
1) chronic: cognitive behaviour therapy (CBT)
2) biofeedback, relaxation
3) physical +/- occupational therapy
4) lifestyle modification
- sleep hygiene
- stress management
- mindful posture (prevent neck strain)
- headache diary
tldr clinical phases of migraine
1) prodrome
2) aura
3) headache (ictal)
4) postdrome
5) interictal
prodrome of migraine
1) duration: ≤ 48 hrs
2) location
- activation of hypothalamus & neuropeptides in homeostatic function
3) symptoms
- fatigue, food craving, nausea, cognitive symptoms, neck discomfort, photophobia & phonophobia, mood change
aura of migraine
1) duration: 5 - 60 mins
2) pathophysiology
- cortical spreading depression (CSD)
** initial wave of neuronal depolarisation within grey matter -> inhibit cortical activity -> change in synaptic activity, extracellular ion concentration, blood flow, metabolism
** activate trigeminovascular system -> aura symptoms
3) aura symptoms
- visual aura: Scotoma, fortification spectrum
- sensory disturbance
- speech disturbance
- motor symptoms
headache (ictal) of migraine - duration
4 -72hrs
headache (ictal) of migraine - pathophysiology
1) neuropeptides (CGRP)
- implicated in head pain & other symptoms
- neurogenic inflammation, peripheral and central sensitisation of trigeminovascular and other systems
2) sensitisation of central trigeminovascular system
- primary nociceptors + central trigeminovascular neurons
- altered sensory processing and brainstem structure -> severity of allodynia and hypersensitivity to pain in migraine
3) photophobia
- retinal and trigeminal nociceptive input converge in thalamus and project to nociceptive areas of cortex -> exacerbate migraine headache by light
headache (ictal) of migraine - symptoms
1) head pain
- unilateral or bilateral
- moderate to severe
- pulsating or throbbing
- aggravated or causes avoidance of routine activities of daily living
2) photophobia, phonophobia, N/V, allodynia, neck discomfort, cranial autonomic symptoms, cognitive symptoms, fatigue
postdrome of migraine
1) duration: ≤ 48 hrs
2) symptoms: photophobia, phonophobia, nausea, fatigue, cognitive symptoms, neck discomfort, difficulty concentrating
interictal of migraine
1) pathophysiology
- regions of brain remain abnormally active (olfactory regions, midbrain, hypothalamus)
2) symptoms: photophobia, phonophobia, cognitive symptoms, fatigue
pathophysiology vs location of brain
1) cortex
- CSD, altered connectivity
- migraine aura and cognitive symptoms
- target: neuromodulation
2) release of CGRP and PACAP
- multiple potential sources/site of action
- headache or other symptoms
- target: small molecule antagonist & antibodies
3) thalamus
- sensitisation and alteration of thalamo-cortical circuit
- sensory sensitivity & allodynia
- target: neuromodulation
4) hypothalamus
- activation in premonitory phase
- premonitory symptoms
- target: hypothalamus peptides and modulators
5) upper cervical nerves
- pain transmission/sensitisation
- neck pain, head pain
- target: local injection, neural modulation
6) trigemino-cervical complex
- pain transmission or sensitisation
- headache and neck pain
- target: medication, neuromodulation