trigeminal neuralgia and Trigeminal Autonomic Cephalalgias Flashcards
neuralgia
definition
- An intense stabbing pain
- The pain is usually brief but may be severe.
- Pain extends along the course of the affected nerve.
- Usually caused by irritation of or damage to a nerve (but not exclusive)
nerves that can be involved in neuralgia pain
4
- Trigeminal (most common)
- Glossopharyngeal and Vagus
- Nervus intermedius (branch of facial nerve)
- Occipital
inicidence of trigeminal neuralgia
4.3:100000 population (USA)
* (5.9 female, 3.4 male)
Usually elderly patient - predominantly in 60’s and above.
* Younger pt = concern
causes of trigeminal neuralgia
3 main
Idiopathic
Classical
* Vascular compression of the trigeminal nerve (MRI needed)
Secondary
* Multiple sclerosis
* Space-occupying lesion
Others: skull-base bone deformity, connective tissue disease, arteriovenous malformation
presentation of trigeminal neuralgia
Unilateral maxillary or mandibular division pain > ophthalmic division
Stabbing pain
* 5 - 10 seconds duration (can feel like longer – cluster of attacks)
Triggers
* cutanoues
* Wind, cold
* touch
* chewing
Purely paroxysmal (symptom free) or with concomitant continuous pain (then superimposed stabbing attacks)
Remissions and relapses
can trigeminal neuralgia present with otuher cranial nerve pain disorders?
yes - on a continuum with other - present hybrid like
Acute spasms of ‘sharp, shooting pain’
* May be more than one division
* May be bilateral
* May have burning component
* May have vasomotor component
typical TN pt
4
- Usually older patient
- ‘Mask-like’ face
- Appearance of excruciating pain (freeze from the pain)
- NO obvious precipitating pathology
trigeminal neuralgia pt - ‘red flags’
3
- Younger patient (>40yrs)
- Sensory deficit in facial region* e.g. hearing loss – acoustic neuroma*
- Other Cranial nerve lesions
ALWAYS test cranial nerves (identify sensory deficit) systematic examination
ALL patients now get MRI
what to always do when suspect TN
ALWAYS test cranial nerves (identify sensory deficit) systematic examination
ALL patients now get MRI
TN drug therapy
first line
3
Carbamazepine - modified release
Oxcarbazepine
Lamotrigine (slow onset of action)
SIDE EFFECTS
TN drug therapy
second line
4
Gabapentin
Pregabalin
Phenytoin
Baclofen
management strategy of trigeminal neuralgia
Should be responsive to Carbamazepine (if tolerated; almost diagnostic criteria)
* Maximise efficacy and minimise side effects
* inc tolerability is to prescribe prolonged release carbamazepine (tegratol)
Often difficult to control pain first thing in the morning
* Can inc night time dose
Pain diary is very helpful to identify modifications necessary to therapy
Can be responsive to local anaesthesia
* Maxillary and mandibular branch of trigeminal branch
* Useful if an attack when in dental chair
carbamazepine side effects
wide range
key ones
Blood dyscrasias
* Thrombocytopenia
* Neutropenia
* Pancytopenia
Electrolyte imbalances (hyponatreamia) – careful if pt on diuretic, PPI (omeprazole)
Neurological deficits
Paraesthaesia
Vestibular problems
Liver toxicity
Skin reactions (including potentially life threatening)
Blood monitoring on weekly basis for 1st month, then monthly – FBC, Us+Es, liver function test
GDP management of TN
if attack there and then – LA; otherwise liaise with GMP or oral med as outwith dental expertise to monitor bloods
TN surgery indications
Not usually recommended if patient managing on medical therapy with moderate drug dose and no significant side effects
Consider surgery:
* when approaching maximum tolerable medical management even if pain controlled
* ‘Younger’ patients with significant drug use – will have many years of drug use