Trigeminal neuralgia is a condition characterized by severe, stabbing, electric shock-like pain in the face that is often triggered by mundane activities like eating or talking. It is caused by compression or irritation of the trigeminal nerve by blood vessels or tumors. Diagnosis is based on the classic symptoms, and treatment involves medications like carbamazepine or surgical procedures to decompress or ablate the trigeminal nerve like microvascular decompression or radiofrequency thermocoagulation. These procedures aim to relieve pain but can also cause sensory loss or other side effects.

1. Trigeminal neuralgia
Speaker: R2 楊芝琳
Supervisor: Dr. 林嘉祥
1. The clinical journal of pain, 18(1), 2002
2. Surgical Neurology 66 (2006), 350–356
3. JADA, Vol. 135, 2004,1713-1717
4. 2007;334;201-205 BMJ

2. IntroductionIntroduction
Neuralgia
 Unexplained peripheral nerve pain
 The most common site: head and neck
 The most frequently diagnosed form:
trigeminal neuralgia (TN)trigeminal neuralgia (TN)
 Fothergill’s disease
 Tic douloureux (painful jerking)
 Mean age: 50 y/o
 Female predominance (male : female = 1:2 ~2:3)

3. Characteristics of trigeminal neuralgiaCharacteristics of trigeminal neuralgia
 paroxysms of severe, lancinating,
electric shock-like bouts of pain
restricted to the distribution of the
trigeminal nerve
 Unilaterally (right side)
 The mandibular (V3) and/or maxillary (V2)
branch or, rarely, the ophthalmic (V1) branch
 Spontaneously attack or triggered by
trigger zone & movement of the face
 Seconds to minutes

4. AnatomyAnatomy

9. Pathogenesis of trigeminal neuralgiaPathogenesis of trigeminal neuralgia
Uncertain
 Traumatic compression of the trigeminal
nerve by neoplastic (cerebellopontine angle
tumor) or vascular anomalies
 Infectious agents
Human herpes simplex virus (HSV)
 Demyelinating conditions
Multiple sclerosis (MS)

10. Types of Trigeminal Neuralgia
Typical TN
Atypical TN
Pre-TN
Multiple sclerosis-related TN
Tumor-related TN
Post-traumatic TN (trigeminal neuropathy)
Failed TN

11. DiagnosisDiagnosis
Classic TNClassic TN
Atypical or mixed TNAtypical or mixed TN
A persistent and dull ache between paroxysms or mild sensory loss

12. TreatmentTreatment
 Medical treatment
 Carbamazepine (Tegretol) – first line
 Oxcarbazepine
 Gabapentin (Neurontin)
 Lamotrigine
 Baclofen
 Phenytoin
 Clonazepam
 Valproate
 Mexiletine
 Topiramate
Second line
Others

13. Mechanism of medical therapy

14. Surgical treatment
 Gasserian ganglion-level procedures
 Microvascular decompression (MVD)
 Ablative treatments
• Radiofrequency thermocoagulation (RFT)
• Glycerol rhizolysis (GR)
• Balloon compression (BC)
• Stereotactic radiosurgery (SRS)
 Peripheral procedures
 Peripheral neurectomy
 Cryotherapy (cryonanlgesia)
 Alcohol block
Neuro-
destructive
procedure
Surgical
decompress

15. Microvascular decompressionMicrovascular decompression
(MVD)(MVD)

19. Mechanism of ablationMechanism of ablation
treatmenttreatment

23. RadiofrequencyRadiofrequency
thermocoagulation (RFT)thermocoagulation (RFT)

24.  CSF flow when entry Mechel’s cave
 45~90 sec. cycles of 60~90℃
 Perceiving a sharp pinprick as a light touch (hypalgesia)
 Divisional cutaneous facial flushing

25. Glycerol rhizolysis (GR)Glycerol rhizolysis (GR)

26.  Test dose: 0.1-0.15 ml
 0.05~0.1 ml at 3~5 min. intervals
 Total dose: 0.1~0.4 ml
 Sensory changes: pain, burning or paresthesia

27. Balloon compressionBalloon compression
(BC)(BC)

28.  0.5~1 ml of contrast
 Pear-shape balloon
 Compression time:
1~7 min.

30. Stereotactic radiosurgeryStereotactic radiosurgery
(SRS)(SRS)

32. Peripheral proceduresPeripheral procedures

34.  Peripheral neurectomy
 Alcohol block
 0.5~1.5 ml of 80~100%
alcohol
 Whole branch & smaller
peripheral nerve branches
 External approach &
intraoral method
 Cryotherapy
 Exposed surgically and
direct application of a
cryoprobe
 -50~-140℃
 3 cycles of 2 min. with a 5
min. thawing period in
between

36. Ganglion-level proceduresGanglion-level procedures vs.
Peripheral proceduresPeripheral procedures
Ganglion-level ablative procedures
 Similar long-term success rate
 Varying degrees of sensory loss
 Balloon compression: least likely to impair
corneal sensation or to cause anesthesia
dolorosa
Peripheral procedures
 High recurrence rates
 No benefit over ganglion-level procedures
 Reserved for emergency use

37. Flow chart of the current practice of surgery for TN at UCLA.

38. ThanksThanks for yourfor your
attention!!attention!!

41. (a) Thermal lesion of trigeminal nerve.(a) Thermal lesion of trigeminal nerve. (b) Mislocation of the electrode.(b) Mislocation of the electrode.
(c) Expansion of thermal energy to neighboring neural structures.(c) Expansion of thermal energy to neighboring neural structures.