Key Points

  • Trigeminal neuralgia.

  • Glossopharyngeal neuralgia.

  • Headache disorders including migraines, cluster headaches and temporal arteritis.

  • Burning Mouth Syndrome.

  • Atypical facial pain and atypical odontalgia.

Aetiology of Facial Pain

  • Local—teeth/jaws.

  • Psychogenic—psychosomatic/atypical facial pain/Burning mouth syndrome → associated anxiety/TMJ.

  • Referred—Angina/oesophagus/neck/chest.

  • Neurological—Trigeminal/MS/space-occupying lesion/herpes zoster.

  • Vascular—Migraine/temporal arteritis/cluster headaches.

Trigeminal Neuralgia

  • Disorder of cranial nerve V: intense paroxysmal pain with one or more divisions.

  • 3–6/100,000: more common in females—incidence and severity increase with age → Usually 50–70 years.

Causes

  • Compression of trigeminal nerve root by artery in middle cranial fossa (pons): 80–90%, rarely by aneurysm/AV malformation.

  • Nerve demyelination: suspect MS in younger patients.

  • Others: CNS.

  • Achondroplasia.

  • CPA Lipoma/schwannoma/pituitary tumour/sarcoid.

  • Charcot-Marie-Tooth.

Symptoms

  • Paroxysmal pain: Intense, lancinating, burning pain “like electric shock”—lasts seconds/minutes.

  • Frequency varies—may be multiple times, almost always unilateral.

  • Many patients have trigger points—stimulated every day, with period remission and relapse, worsen overtime.

  • Eating.

  • Talking.

  • Washing.

  • Shaving.

  • Toothbrushing.

Investigations

  • Complete neurological examination, look for signs/symptoms of multiple sclerosis (multiple defects):

    • Vision.

    • Weakness.

    • Limbs.

MRI brain if:

  • Atypical features.

  • Patient age <50, look for intracranial lesions/MS.

  • Consider microvascular decompression.

Management—Medical First Line Treatment

  • Most effective anticonvulsants: carbamazepine 100 mg BD (up to 1600 mg in 3–4 divided doses), follow-up with wean after six months, early side effects decrease with time, must monitor FBC, U&Es and LFTs.

  • Leucopenia.

  • Rashes/Nausea and vomiting/dizziness/headaches/diplopia.

  • Ox carbamazepine: induces hepatic enzymes to a less extent.

  • Unlicensed use for trigeminal neuralgia.

  • Usually 300 mg/BD up to 600 mg/daily.

  • Usually 600 mg–2400 mg/divided doses daily.

  • Review in facial pain clinic and wean eventually.

  • Gabapentin/lamotrigine also used as second-line agent.

  • Severe cases I.V. phenytoin in a crisis.

  • Start with small initial dosages and then increase. A few patients may be unresponsive or unable to tolerate side effects. Consider surgery adjuvant with neurosurgical assessment.

Peripheral Procedures

  • Cryotherapy/chemical destruction/radiotherapy ablation.

  • Stereotactic (gamma knife).

Options:

Operative:

  • Nerve blocks with alcohol/phenol—temporary relief (up to 2 years).

  • Avulsion of the superior/inferior orbital nerves—prolonged pain relief.

  • Fogarty balloon inflation—ganglion in Meckel’s cave (or glycerol injection).

  • Radiofrequency thermocoagulation—site of facial tingling produced by electrical stimulation of needle inserted into trigeminal ganglion. When site of tingling corresponds to trigger spot, thermocoagulation produces analgesia of the appropriate area.

  • Microvascular decompression—exploration of cerebellopontine angle (CPA) reveals blood vessel in contact with trigeminal nerve root—Separation using non absorbable (Teflon) sponge can produce relief in symptoms.

Risks

  • Permanent.

  • Paraesthesia/anaesthesia.

  • Dolorosa (severe continuous pain within distribution of nerve).

  • Pain relief = 80–85% remain pain free for 5 years.

  • Young = microvascular decompression (MVD).

  • Elderly/frail = interventions.

Surgery Risks:

  • Damage to cranial nerves V, VII, VIII.

  • Vascular damage.

  • Post-operative weakness.

  • If sensory loss to cornea = risk of scarring, have eyelid shut until able to test corneal reflex—need special glasses with sides.

  • Can get relapse after MVD—consider re-operation as vessels move or material dislodged.

Glossopharyngeal Neuralgia

  • Rare—similar to trigeminal = pain felt at base of the tongue and fauces on one side.

  • TN:GN 100:1.

Symptoms

  • Poorly localised—affects tonsils, tongue base, ear/and intra-auricular area.

  • Patient often point to behind angle of mandible—symptoms often treated as TMJD.

  • Trigger point difficult to identify = yawning/swallowing.

Investigations

  • Topical LA to ipsilateral tonsils/pharynx—immediate relieves symptoms, but short acting *Diagnostic.

  • MRI—Space-occupying lesion in cranial cavity or jugular foramen/MS.

Management

  • Medical similar to management of trigeminal.

  • Surgical—MVD.

  • 75% works.

  • Risks—morbidity/mortality.

  • Headaches: many causes.

Migraine

  • Primary recurrent headache disorder.

  • More common in females.

  • Usually commonest in adolescence.

  • Termed ‘hemicrania’ as it affects half of the head.

Cause

  • Possible relationship to abnormal 5-HT (serotonin) activity—leading to initial vasoconstriction of portions of cerebral arteries, followed by compulsory vasodilation, with cerebral oedema and pain.

Precipitant

  • Hormonal factors including Oral Contraceptive Pill (OCP).

  • Diet—chocolate/bananas, stress, sleep deprivation, bright/flashing lights.

May Have Preceding Aura

  • Visual hallucination—flashing lights/decrease in color, visual disturbance.

  • Motor—temporary motor palsy.

  • Speech—aphasia.

  • Severe unilateral headache—initially poorly localised, becomes localised to temporal/frontal/orbital region.

  • Photophobia/nausea/vomiting.

  • Attacks decrease with age—may totally resolve.

Management

  • Acute attacks: Triptan (5-HT antagonist) plus NSAID/paracetamol.

  • Prophylaxis: Topiramate or propranolol, acupuncture.

Cluster Headaches

  • Exquisite pain of midface/upper face—centred around eyes.

  • Attacks occur in temporal groups/clusters—extended periods of remission between attacks.

  • Often positive FH=Family history.

  • 80% are smokers.

  • 30–40 years.

  • Less common than migraines.

  • Male:Female 6:1.

  • 1:10,000 males/year.

Cause

  • Unknown, allergic basis with mast cell release and vasodilatation.

  • Associated with sleep apnoea, and low oxygen saturation.

  • Alcohol, cocaine, GTN spray.

Symptoms

  • Severe unilateral episodes of burning/lancinating pain in and around the orbit/frontal/temporal.

  • Abrupt onset—lasts for 15 min to 3 h—often wakes patient at night.

  • Begins same time every day (alarm clock headache—may have multiple episodes every day).

May be Associated with Autonomic Symptoms

  • Conjunctival vessel congestion.

  • Eye watering.

  • Nasal stiffness.

  • Facial Flushing.

  • Diagnosis.

  • Clinical/MRI.

Management

  • Acute attacks.

  • Oxygen may abort attacks and its effectiveness diagnostic.

  • Subcutaneous triptan.

  • Prophylaxis.

  • Verapamil drug of choice.

  • Nifedipine.

  • Lithium.

  • Ergotamine.

  • *Distinguish from chronic paroxysmal hemicrania—respond to indomethacin.

Giant Cell Arteritis

  • Multifocal vascular affecting the cranial arteries.

  • Unknown aetiology.

  • Systemic vascular—large/medium vessels especially branches external carotid.

  • Females > Males.

  • Average onset—70 years.

  • Related to polymyalgia rheumatica (PMR).

  • Genetic predisposition possible.

Symptoms

  • Unilateral headache—initial burning—throbbing.

  • Usually temporal/or occipital artery.

  • Lingual/facial/maxillary arteries may get involved leading to claudication on eating/drinking.

  • Affected vessels feel hard/tender.

  • Tongue ischaemia if lingual artery.

  • TIA/CVA.

  • Left untreated.

  • 25% develop visual problems.

  • Due to central retinal artery involvement—which may be bilateral—loss vision.

Diagnosis

  • Increased ESR 60–100 (although can be normal), normocytic normochromic anaemia.

  • Temporal artery biopsy with granuloma formation.

Management

  • Prednisolone >50 mg daily.

  • I.V. methylprednisolone first if visual loss.

  • Urgent ophthalmological assessment.

  • Consider rheumatology referral.

  • Decrease steroid with resolution of headache—ESR may take month/years to normalise.

  • PPI.

  • Osteoporosis cover—bisphosphonates.

  • Calcium/Vitamin D.

  • Aspirin (decrease CVA).

Burning Mouth Syndrome

  • Burning sensation of oral mucosa (usually tongue—glossopyrosis) in absence of any pathology.

  • Common 5 in 100,000—much higher middle aged and elderly.

  • Female:Male 16:1.

  • Age >50 years.

Aetiology

  • Unknown.

  • Psychogenic.

  • Increased in anxiety/depression/stress.

  • Obsession.

  • Cancerphobia.

  • First exclude organic cause of burning.

  • Local.

  • Xerostomia/chronic mouth breathing/mechanical trauma/referred pain/trigeminal neuralgia/atypical facial or neuralgia/angioedema/candidiasis/TMJD/submucous fibrosis/trauma lingual nerve.

Systemic

  • B vitamins, folate, zinc, iron.

  • Diabetes mellitus / GORD/ hypothyroidism/ oestrogen deficiency/ Parkinson’s / AIDS.

Symptoms

  • Dry mouth/altered or bad taste.

  • Burning sensation affecting tongue and anterior palate, less common in lips.

  • Aggravated by certain food—usually bilateral.

  • Does not wake patient, but often present on waking.

  • Normal examination.

Investigations

  • FBC/haematinics/swab candida—all normal.

  • Tricyclic antidepressants—side effects.

  • Arrythmias/heart block.

  • Postural hypotension/tachycardia.

  • ECG changes.

  • Dry mouth/blurred vision/constipation/urinary retention.

Management

  • Reassurance.

  • Avoid stimulating factors.

  • Cochrane review: Amitriptyline 10 mg daily (max 75 mg daily titrated/Clonazepam 1 mg TDS mouthwash.

  • Tricyclic antidepressant—same patients respond.

  • 2nd line: Pregabalin 150 mg divided doses daily/75 mg BD.

  • Tricyclic antidepressants: nortriptyline: 10–25 mg once at night (maximum 75 mg once at night); less sedative effects than amitriptyline.

  • CBT: shown in RCTs to help patients manage symptoms—as medical management often disappointing.

Atypical Facial Pain

  • Diagnosis of exclusion.

  • Constant chronic dull ache.

  • Most common in females—middle age/elderly.

  • Can get intermittent/severe episodes, may be bilateral.

Clinical

  • Often difficult for patient to describe—deep constant ache or burning.

  • No anatomical bundles—cross midline moves to different sites.

  • Maxilla > mandible.

  • Does not stop sleeping, but may awaken with pain.

  • Often exacerbated/initiated by dental treatment.

  • Often have other complaints: IBS/TMJD/back pain/neck pain/dry mouth—diagnosis from trigeminal neuralgia is difficult (lack of trigger, vague distribution).

Investigations

  • MRI/Bloods/Biopsy—nerve.

Management

  • Tricyclic antidepressant—some effect on symptoms—no adequate RCT to show this.

  • 30% respond gabapentin. Dose regime

    1. (a)

      Day 1: 300 mg/OD

    2. (b)

      Day 2: 300 mg/BD

    3. (c)

      Day 3: 300 mg/TDS

  • Pain team/CBT.

Atypical Odontalgia

Pain tooth/site of extraction—sharp/aching/throbbing, burning—exclude pathology

Management Includes:

  • Topical capsaicin—some benefit, need for several weeks.

  • EMLA.

  • Tricyclic antidepressant.

  • Gabapentin.