TRIGEMINAL NEURALGIA

2. Introduction
Definition
Historical review of trigeminal neuralgia
Aetiology
General characteristics
Clinical characteristics
Diagnosis
Treatment modalities
Management
Pathogenesis
CONTENTS

3. INTRODUCTION:
Most debilitating form of neuralgia that affects the
sensory branches of the Vth cranial nerve.

4. DEFINITION
“sudden, usually unilateral, severe, brief, stabbing, recurrent episodes
of pain in the distribution of one or more branches of the trigeminal
nerve”
….The International Association for The Study of Pain (IASP)

5. Historical review of trigeminal neuralgia:
JOHN LOCKE in 1677 gave the first full description with
its treatment.
NICHOLAS ANDRE in 1756 coined the term ‘Tic
Doloureux’.
JOHN FOTHERGILL in 1773 published detailed
description of trigeminal neuralgia.

6. Aetiology:
Usually idiopathic
Demyelination of the nerve
Multiple sclerosis
Petrous ridge compression
Post – traumatic neuralgia
Intracranial tumours
Intracranial vascular abnormalities
Viral etiology

7. TN is classified into
TYPICAL TN AND ATYPICAL TN.
In common terminology,
1. typical TN includes paroxysmal pain alone
2. atypical TN includes paroxysmal pain and constant pain.
PRIMARY OR SECONDARY
1. Primary or idiopathic TN does not have a clear cause.
2. Secondary or symptomatic TN is due to a primary cause, such as
tumor, multiple sclerosis (MS), or neurovascular compression.

9. GENERAL CHARACTERISTICS:
Incidence:
Age:
Sex:
Affliction for side:
Division of trigeminal nerve
involvement:
8 : 1,00,000
5th – 6th decade of life
Female > male : 1.6 > 1.0
Right > left
V3 > V2 > V1

10. CLINICAL CHARACTERISTICS:
•Sudden, unilateral, intermittent paroxysmal, sharp,
shooting, lancinating, shock like pain, elicited by slight
touching superficial ‘trigger points’ which radiates from
that point, across the distribution of one or more
branches of the trigeminal nerve.
•Pain is usually confined to one part of one division of
trigeminal nerve.
•Pain rarely crosses the midline.
•Attacks do not occur during sleep.

11. •Pain is of short duration, but may recur with variable
frequency.
•In extreme cases, the patient will have a motionless face
– the ‘frozen or mask like face’.
Common trigger zones include:
Cutaneous
Corner of the lips
Cheek
Ala of the nose
Lateral brow
Intraoral
Teeth
Gingivae
Tongue

12. Various stimuli precipitating the episode:
a. Touching
b. Applying heat or cold to cheek
c. chewing
d. Yawning
e. Talking
f. Wind blowing on the face
g. Gustatory stimuli & vibration

13. DIAGNOSIS:
1. From well taken history
2. CT – scan
3. MRI
4. Diagnostic nerve block

14. TREATMENT MODALITIES:
MEDICAL SURGICAL

16. MEDICAL MANAGEMENT:
It is the first line approach for most of the patients.
CARBAMAZEPINE:
Trade name: Tegretol
Carbitrol
Dosage: 100 – 2000 mg/day
Side effects: visual blurring
skin rashes, leukemia,
thrombocytopenia,
aplastic anemia

17. PHENYTOIN:
Trade name: Dilantin
Dosage: 200 - 600 mg/day (qid)
Side effects: slurred speech
abnormal movement
swelling of lymph glands
gingival hypertrophy
folate deficiency
It is usually used in conjunction with carbamazepine.

18. GABAPENTIN:
It is more expensive than other drugs but has a less side
effects.
Trade name: Neurontin
Dosage: 100 - 5000 mg/day (tid-qid)

19. BACLOFEN:
It is a GABA agonists.
These drugs reduces the central projection of painful
afferent impulses.
Trade name: Lioresal
Dosage: 10 mg (tds)
Side effects: fatigue
vomiting

20. TRICYCLIC ANTIDEPRESSANTS:
Amitriptyline
Nortriptyline
Imipramine
10 – 300 mg/day
10 – 150 mg/day
10 – 300 mg/day

21. SURGICAL MANAGEMENT:
PERIPHERAL INJECTION:
It has been known that injection of destructive substance
into peripheral branches of the trigeminal nerve,
produces anaesthesia in the trigger zones or in areas of
distribution of spontaneous pain.
(A) LONG ACTING ANAESTHETIC AGENTS:
bupivacaine with or without corticosteroids may be
injected at the most proximal possible nerve site.

22. (B) ALCOHOL INJECTION:
0.5 – 2 ml of 95 % absolute alcohol can be used to block
the peripheral branches of the trigeminal nerve.
Aim is to destroy the nerve fibres.
It produces total numbness in the region of distribution
of the nerve that was anaesthetized.
Complication:
Necrosis of the adjacent tissue
Fibrosis
Alcohol induced neuritis

23. PERIPHERAL NEURECTOMY (NERVE AVULSION):
Oldest & most effective peripheral nerve destructive method
Can be repeated & relatively reliable technique.
It acts by interrupting the flow of a significant number of afferent
impulses to central trigeminal apparatus.
Performed commonly on infraorbital, inferior alveolar, mental and rarely
lingual.
Disadvantage:
May produce
full anaesthesia
deep hypoesthesia

24. INFRAORBITAL NEURECTOMY:
(i) Conventional intraoral approach
(ii)Braun’s transantral approach

25. INFERIOR ALVEOLAR NEURECTOMY:
(i) Extra oral approach
(ii)Intra oral approach

26. LINGUAL NEURECTOMY:

27. CRYOTHERAPHY:
• Barnard first used cryotheraphy in 1981 for the treatment
of the trigeminal neuralgia.
• After identifying the affected nerve , it is then exposed to
the cryoprobe intraorally.
• Direct application of cryotheraphy probe at temperatures
colder than -600 C are known to produce Wallerian
degeneration without destroying the nerve sheath itself.
• Nerve is exposed for 2 mm freeze followed by 5 mm thaw
cycle.
• The freeze – thaw cycle is repeated at least 3 times.

28. GASSERIAN GANGLION PROCEDURES:
PERCUTANEOUS RHIZOTOMY:
This is done on the Gasserian
ganglion which involve either
mechanically or chemically
damaging parts of the
trigeminal nerve.

29. (A) Controlled radiofrequency thermocoagulation:
It was first introduced by Kirschner (1931) & later
modified by Sweet (1970).
Technique:
The patient is sedated with a short acting sedative
and vital signs are monitored.
The electrode is inserted through the cheek under
fluoroscopy into foramen ovale.
The patient is awakened briefly to accurately
locate the position of the electrode.

30. Indication:
Toxicity of drugs
Failure of response to the other
modalities
Dependence on the drugs for life time.
Elderly patients
Medically compromised patients

31. Advantages:
Comparative low rate of recurrence
Zero mortality
Thermocoagulation preserves the motor function
of the trigeminal nerve
Can avoid major surgical procedure
Disadvantage:
May cause
anaesthesia dolorosa
loss of corneal reflex
Meningitis (rarely)

32. (B) Percutaneous glycerol rhizotomy:
Glycerol is a neurolytic alcohol which can be used to
chemically destroy the nerve root.

33. Advantages:
Simple technique
Lower incidence of anaesthesia
dolorosa
Complication:
Post operative headache, nausea, vomiting
Meningitis
Post operative herpes simplex perioralis

34. (C) Percutaneous balloon compression:
This is a mechanical means of destruction of the
trigeminal nerve introduced by Mullan & Lichtor in 1980.
Technique:
A no. 4 Fogarthy’s catheter is introduced with
fluoroscopic guidance.
A 0.7 mm balloon is inflated for 1 – 2 minutes.

36. OPEN PROCEDURES ( INTRACRANIAL PROCEDURES):
(A) Microvascular decompression of the trigeminal nerve
sensory root:
Procedure popularized in 1967 – 1976 by Jannetta.
Most commonly performed intra cranial open procedure.
The root is examined under the
microscope

37. A compressing branch of the
superior cerebellar artery will be
seen medial to the nerve at the
root entry zone.
Incision is made over the mastoid area

38. Then the trigeminal nerve is freed
from the compressing / pulsating
artery.
After freeing the nerve, the
nerve is separated from the
artery by placing a piece of Teflon
between them.

39. Non absorbable insulating sponge
may also be placed.

40. (B) Trigeminal root section:
(a) Extradural sensory root section:
It is no longer used now.
In this, sensory root is divided, sparing the motor root, as
close to the brainstem as possible.
Disadvantage:
Profound sensory loss
High incidence of anaesthesia dolorosa

41. (b) Intradural rhizotomy:
This is an intradural procedure that is done when the pain
recurs after MVD.
This is usually done in the posterior cranial fossa.
It can be selective or complete.
(c) Trigeminal tractotomy:
It is also known as the medullary tractotomy.
This is not usually done.
The descending tract of the trigeminal nerve is
sectioned at the junction of the cervicomedullary
region.

42. STEREOTACTIC RADIOSURGERY (GAMMA KNIFE):
This has been recently introduced in treatment of
trigeminal neuralgia.
This consists of multiple rays of high energy photons
concentrated with absolute accuracy on the target, i.e.,
on the trigeminal nerve root.
This can be used to destroy the
specific components of the
nerve.
The source of radiation is Co60.

43. CONCLUSIONS
Although relatively rare, trigeminal neuralgia is a debilitating and
complex facial pain condition which requires a patient centred,
multi-disciplinary approach to its management. Currently, the
guidelines and associated evidence are insufficient to be able to
recommend definitive management, and further high quality
research is required.

44. THANK YOU
A patient narrative which clearly demonstrates the severity and impact of TN pain.
“Even as the spasm eases, you know that the relief is only
because your nerves have been overcome by the pain. It will
come back tomorrow if it doesn't come again today. You know
that the demon is never going to go away. It does not care if
you are a nice human being. It does not care if you pray
hourly. It's only mission in your life is your pain. And it is