Trigeminal Neuralgia Flashcards
pain can be nociceptive, neuropathic and nocicoplastic
explain these
nociceptive - normal physiological response
neuropathic - disease of somatosensory nervous system [TN**]
nocicoplastic - increases sensitivity from altered function of pain sensory pathways in CNS + periphery
describe TN
recurrent, bilateral, brief electric shock pains
abrupt onset + termination
limited distribution to 1+ divisions of trigeminal nerve
triggered via innocuous stimuli
develop with no apparent cause or another disorder
may have concomitant continuous pain of mod intensity
78% suicidal thought
red flags in orofacial pain
sensory motor defects
deafness
loss of balance [indicates space occupying lesion]
optic neuritis
history crania-facial malignancy
bilateral TN [indicates MS?]
systemic symptoms
<30 y/o
name the 3 types of TN
1 - classical
2 - secondary
3 = idiopathic
explain classical TN
without apparent cause except neurovascular compression
paroxysmal concomitant continuous pain
neurovascular conflict via trigeminal and cerebral artery
compression -> demyelination -> ectopic firing
explain secondary TN
underlying disease
- MS, space occupying lesion, skull-base deformity, connective tissue disease
nerve hyper excitability
pathological process -
decreased glial/myelin coverage @ pons
explain idiopathic TN
no known cause
MRI reveals unknown
paroxysmal
no conflict but unregulated sodium ion inflow therefore depolarisation
TN triggers
not all have
eating, talking, smiling, brushing teeth
cold wind, temp change, stress
TN primary care management
carbamazepine =
-800-1200mg over 4 doses, 1600 max
-check interactions
-increased fall risk in elderly
-blood monitoring [FBC, U+E, LFT]
-risks = hyponatraemia, falls, unsteadiness confusion, rash, skin reactions
LA if severe pain
urgent referral OM/Maxfax for definitive advice
TN secondary care management
MRI to exclude MS/space occupying
medication optimisation =
- carbamazepine
-oxcarbamazepine [well tolerated, effective, lower evidence of safety]
-lamotrigin, baclofen, gabapentin, pregabalin
neurosurgery - consider
explain the neurosurgery techniques used in TN
microvascular decompression =
GA, must have neurovascular conflict, moving of artery, 6hrs
decreased risk of numbness, increased surgical risks [CSF leak, hearing loss, stroke, infection]
neuroablative procedures =
balloon dilation, 30mins, GA
percutaneous needle in Meckels cave, balloon compresses nerve
increased risk of numbness, decreased surgical risks
stereotactic radiosurgery =
minimally invasive, no GA
what are trigeminal autonomic cephalalgias
how would you manage them
headache disorders
similar to TN BUT autonomic features
cluster headache, paroxysmal hemicrania, SUNCT/SUNA, hemicrania continua
GP/neurology referral
exclude odontogenic
MRI
SUNCT /SUNA
short acting unilateral neuralgia form headache
-> with conjunctival infection and tearing
-> with cranial autonomic symptoms
