Trigeminal Neuralgia Flashcards
what is trigeminal neuralgia
disorder of trigeminal nerve seeing episodes of unilateral, intense stabbing/ electric - shock like pain.
most common in mandibular and/or maxillary branch(es)
discuss the classification of trigeminal neuralgia
classical - caused by neurovascular compression in nerve root entry zone
idiopathic - unknown cause
secondary - caused by underlying disease such as tumours, artery malformations or MS
classical trigeminal neuralgia
caused by neurovascular compression in nerve root entry zone. most commonly the superior cerebellar artery compressing the nerve root between itself and the pons leading to to demyelination of nerve fibres which then start firing ectopically
discuss the epidemiology of trigeminal neuralgia
rare , 4-8/100000
females more than males, 2:1
name 3 clinical features of trigeminal neuralgia
- paroxysmal attacks of pain lasting less than 2 mins
- very rarely occurs bilaterally and rarely affects v1
- presence of trigger zone, usually near centre of face. brought on by innocuous stimuli e.g shaving, talking, toothbrushing
- majority of patients asymptomatic between attacks
who sets out the diagnostic criteria for trigeminal neuralgia
ICHD - 3
discuss the diagnostic criteria for trigeminal neuralgia (ICHD 3) (4)
1 - recurrent paroxysms of unilateral facial pain in one or more divisions of trigeminal nerve with no radiation beyond
2 - pain with characteristics (lasts up to 2 mins, severe, electric shock like)
3 - triggered by innocuous stimuli
4 - no better ICHD 3 diagnosis
name 3 drugs that may be used to treat TN
carbamazepine
lamotrigine
gabapentin
carbamazepine as a treatment for TN
- MOA
usually first line drug treatment
an anticonvulsant which blocks VGSCs therefore decreasing nerve activity
carbamazepine as a treatment for TN
- dose
starts with 100/200mg day increasing to max dose of 1600mg day
carbamazepine as a treatment for TN
- side effects
dizzyness, tiredness, drowsiness, nausea, leukopenia, ataxia
what are the non pharmacological treatment options for TN
surgery
non invasive electrical stimulation
briefly discuss surgery as an option for TN management
should only be offered if pharmacological methods inadequate
- gamma knife surgery (utilises radiation, risk of sensory complications)
- microvascular decompression surgery (good pain relief but very invasive)
what is trigeminal autonomic cephalgias
severe unilateral head pain predominantly affecting V1
usually cranial parasympathetic features on ipsilateral side - nasal congestion, eyelid oedema, ptosis, miosis
various different types (cluster headaches, paroxysmal hemicrania)
cluster headache
type of TAC
excruciating unilateral pain lasting 15 mins to 3 hours
attacks present in clusters - bouts for 1-3 months then remission period with no attacks