HeadacheD. Gelb11.10.06

I. episodic symptoms - focalA. TIAB. migraine (in some ways is a diffuse process)C. seizure

II. clinical: migraine, tension, and friendsA. etiology

1. primary: an inherent predisposition (majority of headaches are primary) a. migraineb. tensionc. clusterd. other

2. secondarya. infectionb. tumorc. hypertensiond. other

B. migraine: 1. characteristic features

a. unilateral (focal feature)b. throbbing/pounding/pulsating (may be pulling, squeezing, vice-like, stabbing)c. nausea/vomitingd. photophobia/phonophobiae. aura (focal feature)

2. diagnostic criteria (at least 5 attacks)a. attacks last 4-72 hours untreatedb. headache has at least 2 of the following

i. unilateralii. pulsatingiii. moderate or severeiv. aggravated by routine physical activity

c. during headache at least one of the followingi. nausea and/or vomitingii. photophobia and phonophobia

3. typical aurasa. visual

i. scintillating scotoma (sparkling/shimmering/variable visual field cut)ii. fortification spectre (jagged edge surrounding abnormal visual field area)iii. may be black, white, or with colorsiv. may lead to total blindness or just some partv. described as looking through broken glassvi. may occur before, during, or after the headache

b. unilateral numbness or weaknessc. dysphasiad. basilar

i. vertigoii. diplopiaiii. ataxia

C. pathophysiology: neurogenic inflammation, spreading depression1. intracranial pain-sensitive structures

a. arteries i. circle of Willis and first few centimeters of branchesii. dural

b. large veins and dural venous sinusesc. portions of dura near blood vesselsd. not brain parenchyma

2. pain-sensitive structures outside the skull cavitya. external carotid and its branchesb. skin, scalp

c. fascia, musclesd. teethe. sinus mucosaf. cutaneous nervesg. cervical nerves and nerve routes

3. referred pain

a. pain referred from vessels to trigeminal nerveb. proposed mechanisms

i. branched fibers of single afferent - these fibers have not been documentedii. convergence of central projections (discrimination is lost centrally)

4. neurogenic inflammation

a. nociceptive terminals in brain as well b. send signals from disturbed blood vessels to trigeminal ganglionc. terminals may also release substance P and create injury as they are transmitting information

i. substance P causes many inflammatory changes (ex. degranulation of mast cells)ii. once signal begins down nociceptive terminal, nothing stops it from going down another

branch (and stimulating release of substance P) iii. called “neurogenic inflammation” because of the amplification process though the neurons

5. descending pain-modulating pathways a. primary nociceptive neuron synapses on nucleus caudalisb. message crosses nervous system and goes up ascending pathwayc. inhibitory modulation from same pathway as pain pathway in bodyd. starts in periaqueductal gray (PAG) dorsolateral pontine tegmentum rostral

ventromedial medulla (including raphe nucleus)e. raphe nuclei innervate blood vessels diffusely throughout the brain - could transmit inhibitory

signal across brain once it starts

f. central activation of pain-modulating systems: similar to circuit for episodic memory (limbic system, amygdala, cortec, etc)

g. whole process is related to inhibition from the cortex6. aura: rate of progression (Lashley)

a. progress across cortex 2-3 mm per minuteb. spreading depression

i. precipitated byI. mechanical deformationII. electrical stimulationIII. application of glutamate or KCl

ii. depressed zone characterized byI. marked depolarization of neuronsII. marked increase in extracellular K+III. marked decrease in extracellular Ca++ and Na+

iii. depressed zone followed by I. wave of markedly increased blood flowII. followed by (2-3 minutes later) wave of moderately reduced blood flow for 60-90

minutes7. synthesis: endogenous (hormones, stress) and exogenous (wine, chocolate, processed meats) triggers

cortical hyperexcitabilitya. spreading depression

i. aura ii. further disinhibition of trigeminal nucleus

b. disinhibition of trigeminal nucleus orthodromic pain signali. antidromic neurogenic edema (inflammation)ii. referred pain (to scalp, neck, etc)

D. migraine vs tension headachemigraine tension

unilateral bilateralthrobbing pressurephoto/phono phobia little or nonenausea/vomiting little or noneaura none“vascular” “muscle tension”

1. many patients have both2. many headaches are intermediate3. patients with migraine have tense muscles4. patients with tension have blood flow abnormalities5. same medications work for both

E. explanations for patients1. headaches appear to be caused by chemical changes in the brain2. vascular phenomena and muscle tension appear to be results of the underlying pathology, not causes3. significance of the distinction between migraine and tension is not clear4. treatments that work for migraines work for tension

F. pathology: none

G. diagnosis: clinical (need to know clinical syndromes)1. differential for primary headache

a. migraine/tension b. clusterc. trigeminal neuralgia (and glossopharyngeal neuralgia)d. chronic paroxysmal hemicrania (and related conditions)e. atypical face pain

2. cluster headachesa. characteristics

i. last 4-8 weeksii. once or twice a yeariii. within a cluster

I. one or more headaches a dayII. at least one of the headaches at the same time each day (often during sleep)

iv. men:women = 6:1b. properties of the heachache

i. explosive (patients try to move around, may hit head)ii. unilateral, almost always same sideiii. ipsilateral lacrimation, injection, nasal congestion, rhinorrhea, sometimes Horner’siv. 30-120 minutes

3. trigeminal neuralgiaa. paroxysmal, “electric shock like”b. lasts < 1 second, often in volleysc. trigger zone commond. superimposed dull ache may occure. onset usually after age 50f. can be precipitated by dental diseaseg. can be precipitated by MS

4. chronic paroxysmal hemicraniaa. unilateralb. ipsilateral lacrimiation, injection, nasal congestion, rhinorrheac. average 13 minutes longd. average 14 attacks per daye. women:men = 5:1

5. atypical facial paina. some features of migraineb. some features of neuralgiac. some features of neither

H. treatment1. migraine/tension

a. eliminate triggers when possibleb. use abortives early in headache and repeat if necessary

i. aspirinii. acetaminopheniii. NSAIDsiv. acetaminophen/isometheptene/dichlorphenazone (Midrin or Duradrin)v. triptans (drugs end with -triptan)vi. ergotsvii. chlorpromazine (anti-nausea medicine with an abortive effect)viii. ER use

I. triptansII. dihydroergotamine (DHE)III. IV chlorpromazineIV. 100% oxygenV. IV valproic acidVI. steroid burst (solumedrol or hydrocortisone)VII. IM ketorolacVIII. intranasal lidocaine

c. patients requiring large quantities of abortives should be on prophylactic medicationi. drugs used: naproxen, β-blockers. tricyclic antidepressants (better than SSRIs for pain

syndromes), valproic acid, gabapentin, topiramate, calcium channel blockers, cyproheptadine,

methylergonovine, methylsergide, tizanide, MAO inhibitors, newer antidepressants, botulinum toxin

d. choice of meds should be based on patient’s other medical problems, side-effect profilee. with prophylactic medications: start at low dose and increase as necessary (and as tolerated)f. once on effective prophylaxis, previously ineffective abortives may workg. after adequate control for 6-12 months, try tapering the prophylactic

2. clustera. to abort headaches: oxygen, sumatriptan, DHE, intranasal lidocaine, intranasal ergotamineb. to terminate cluster: prednisone, verapamil, valproic acid, lithium, ergotamine tartrate or

methylsergide3. trigeminal neuralgia: carbamazepine, gabapentin, baclofen, topiramate, lamotrigine, phenytoin,

amitriptyline 4. paroxysmal hemicrania: indomethacin5. atypical facial pin: standard migraine medications and/or typical medications for neuralgia

III. secondary headachesA. emergencies

1. subarachnoid hemorrhage (SAH)2. bacterial meningitis

B. moderately urgent1. mass lesions2. temporal arteritis3. idiopathic intracrainial hypertension4. spontaneous intracranial hypotension5. cerebral venous thrombosis6. arterial dissection7. sphenoid sinusitis8. systemic malignancy or inflammation

C. rule out emergencies (SAH or meningitis)1. described as “worst headache of life” (severe headache, unlike any the patient has ever had before)2. concerning findings on physical exam

a. feverb. meningeal signsc. focal neurologic deficits (can occur in migraine, but pattern is key)

3. if SAH or meningitis is at all plausiblea. CT of brain (if available quickly)b. LP (unless CT demonstrates SAH or impending herniation)

i. LP findings in SAHI. RBCs: appear within about half an hour, disappear within about half a weekII. xanthochromia (yellow tinge to supernatant of centrifuged CSF): appears within about

half a day, disappears within about half a monthIII. note: if LP was traumatic, the only way to determine if RBCs were from tap itself or from

SAH is to spin down the CSF and examine for xanthochromia ii. LP findings in bacterial meningitis

I. WBCs: typically >1000II. glucose: typically < 1/3 of serum glucoseIII. protein: typically elevated

iii. exceptions occur to all, so all patients should receive empiric AbxD. potential danger signals

1. major changea. recent onsetb. recent change in character of headache

2. examination findingsa. focal neurologic examb. papilledema

3. atypical symptomsa. strongly positionalb. prominent systemic symptoms

E. secondary headache syndromes1. mass lesion: focal progressive2. systemic malignancy or inflammation: prominent systemic symptoms3. temporal arteritis

a. non-specific headache

b. temporal artery tendernessc. jaw claudicationd. elevated SED rate, C-reactive proteine. urgent treatment necessary to prevent visual loss

4. idiopathic intracranial hypertension (IIH): pseudotumor cerebria. diffuse headacheb. often with transient visual symptomsc. worse with bending overd. exam: papilledema, typically obese, 6th nerve palsy sometimes

5. spontaneous intracranial hypotensiona. post-LP headache without the LP: resolves when lying flat, aggravated by sitting up or standingb. sometimes associated with

i. dizzinessii. nausea/vomitingiii. diplopia (6th nerve palsies)iv. blurred vision or visual field defectsv. hyperacusis or tinnitusvi. mental status changes

6. cerebral venous thrombosisa. headachesb. focal neurologic symptomsc. seizuresd. usually in patients with coagulopathy or severe dehydration e. worry during pregnancy or just after delivery

7. arterial dissectiona. neck painb. headachec. focal neurologic symptomsd. may have history of neck trauma or manipulation

8. sinus diseasea. acute sinusitis: typical symptoms (congestion, rhinorrhea, focal tenderness, post-nasal drip)b. exception: sphenoid sinusitis (possible clues: positional component, abnormal smell)c. chronic sinusitis: usually tension/migraine

9. temporomandibular joint disease a. exacerbated by chewing, yawningb. audible click on jaw openingc. TMJ easily dislocated on examd. probably overdiagnosed

10. post-concussion syndrome (post-traumatic syndrome)a. non-secific headache (tension/migraine features)b. various symptoms following one or more of the following

i. neck or back painii. problems with memory and concentrationiii. mood changes, depressioniv. diffuse sensory symptomsv. weaknessvi. sleep disturbance

c. role of litigation controversialF. treatment

1. SAH: see stroke lecture2. meningitis: see infectious disease lecture3. systemic disease: see other courses4. temporal arteritis: steroids5. IIH: acetazolamide, topiramate, repeated lumbar puncture, occasional shunt6. spontaneous intracranial hypotension: blood patch7. arterial dissection: warfarin until recanalization demonstrated8. cerebral venous thrombosis: anticoagulation (heparin, then warfarin)9. acute sinusitis: antibiotics (may need to be given IV in sphenoid sinusitis)10. TMJ disease: soft diet, jaw bracing, surgery11. post-concussion syndrome: treat symptoms