Trigeminal neuralgia (N) Flashcards
Define trigeminal neuralgia.
A facial pain syndrome in the distribution of 1+ divisions of the trigeminal nerve (ophthalmic, maxillary and mandibular divisions)
What is trigeminal neuralgia characterised by?
Some combination of paroxysms of sharp, stabbing, intense pain lasting up to 2 minutes and/or a constant component of facial pain, without associated neurological deficit
What causes the symptoms of trigeminal neuralgia?
Compression of the trigeminal nerve (by a loop of artery/vein)
Secondary causes:
- compression by anomalous/aneurysmal intracranial vessels
- tumour
- chronic meningeal inflammation
- MS
- Herpes Zoster
- skull base malformation
What demographics is trigeminal neuralgia most common in? (2)
- F > M
- 60-70y
What pathogen is trigeminal neuralgia associated with?
Herpes simplex virus
What is the main clinical feature of trigeminal neuralgia?
Unilateral facial pain - sudden, severe, shooting, stabbing pain (like an electric shock, face screws up with pain) followed by a burning ache
Think 5S’s of pain - sudden, severe, sharp, shooting, stabbing
How long does the pain last in trigeminal neuralgia?
Several seconds (up to 2 minutes) and may occur up to 100x a day, recurrent pain
Where does the pain in trigeminal neuralgia occur on the face typically?
Shoots from mouth to angle of jaw on affected side
What are some preceding symptoms you may get before trigeminal neuralgia pain?
Numbness and tingling
What are some triggers for trigeminal neuralgia? (5)
- vibration
- skin contact - washing, shaving
- movements - talking, eating, brushing teeth
- dental prostheses
- exposure to wind
What are some red flag features of trigeminal neuralgia (that mean you refer to a specialist)? (7)
- sensory changes
- deafness / ear problems
- Hx of skin/oral lesions that could spread perineurally
- pain only in ophthalmic division (eye socket, forehead, nose) or bilaterally
- optic neuritis
- Fx of MS
- age of onset <40
What are some risk factors for trigeminal neuralgia? (6)
- increased age
- MS
- prior oropharyngeal/facial trauma
- prior herpetic outbreak
- female
- hypertension
How is trigeminal neuralgia diagnosed?
Clinical diagnosis based on history and features - Hx of paroxysms of sharp, stabbing, intense pain lasting up to 2 minutes
What investigations could you consider for trigeminal neuralgia? (3)
- MRI - if secondary cause suspected
- trigeminal reflex testing - early blink / masseter inhibitory reflex
- intra-oral x-ray if dental cause suspected (caries, fracture, osteomyelitis)
What are some differential diagnoses for trigeminal neuralgia? (10)
- dental caries (single tooth)
- dental fracture (provoked by biting)
- mandibular osteomyelitis
- TMJ syndrome (bilateral, jaw opening restricted)
- migraine
- glossopharyngeal neuralgia
- post-herpetic neuralgia
- temporal arteritis
- atypical facial pain
- trigeminal autonomic cephalgia e.g. cluster headaches
