Trigeminal Neuralgia
- Episodic
lancinating pain to face in trigeminal distribution
- Etiology:
- Compression
of the trigeminal nerve root entry zone at the brainstem by a blood
vessel (SCA is most common)
- Benign
CP angle tumor (meningioma, epidermoid, acoustic)
- Bony
compression (Paget’s disease)
- Multiple
sclerosis
- Trigeminal
injury
- Idiopathic
- Diagnosis:
purely by history (diagnosis is itself a symptom)
- MRI to rule
out mass lesion compressing 5th nerve is important for
treatment planning
- Treatment:
Tailored to the individual patient and may include any combination of the
following:
- Medications
- Analgesics
- Tegretol
(start at small doses 200 mg/day, increase until relief of symptoms or
toxicity)
- Dilantin
(add only if Tegretol alone inadequate)
- Elavil
(start at 25 mg qhs, increase until toxicity)
- Ablative
Surgical Procedures
- Radiofrequency
ablation of Gasserian ganglion
- Utilizes
skull x-ray landmarks to introduce long, thin needle through cheek to
area of Gasserian ganglion by penetrating the foramen ovale, then
producing a heat lesion in the appropriate region of the ganglion
- Transient
herpetic eruptions are uncommon after procedure
- Glycerol
injection – patient under general anesthesia
- Balloon
compression – possibly better for V1 pain (may not denervate large
fibers to cornea)
- Gamma
knife
- Microvascular
decompression – Retromastoid craniectomy to explore the trigeminal nerve
and its root entry zone
- Better long-term
results than other options
- Generally
reserved for young patients who fail medical therapy