3. PRIMARY NEURALGIAS
The most common paroxysmal neuralgia
arises in the trigeminal nerve. Occasionally, it
affects the glossopharyngeal and superior
laryngeal branch of vagus nerve.
The aetiology of this pain is unclear.
It may be due to viral aetiology within the
ganglion, demyelination of intracranial nerve
roots due to compression by small vascular
loops, by dural bands or by narrowing of
foramina.
4. Secondary neuralgias
They arise from irritation of the trigeminal
ganglion or nerves by some identifiable lesion
and may either mimic exactly the primary
paroxysmal pain, or present as a less specific
disturbance.
Important differentiating features are the
associated local sensory or motor impairment
which may or may not be present when the
patient first presents.
The lesion can be either extracranially or
intracranially.
6. Secondary neuralgias:
Intracranial lesions
1. Tumours of posterior cranial fossa
(ex: Schwannoma)
2. Tumors of middle cranial fossa
(Ex: pituitary tumors & aneurysms of
the internal carotid aretry)
3. Multiple sclerosis
7. TRIGEMINAL NEURALGIA
It is defined as sudden, usually unilateral,
severe, brief, stabbing, lancinating,
recurring pain in the distribution of one
or more branches of fifth cranial nerve.
11. General characteristics
Incidence – 4 in 100,000 persons.
Age of occurrence: late middle age or
later in life (5th to 6th decade).
Sex predilection: female (58%)
Affliction of sides: Right side (60%)
Division of trigeminal nerve involvement:
V3 is more common than V2. V1 is
rarely involved (5%)
12. Clinical features
It typically manifests as a sudden,
unilateral, intermittent paroxysmal,
sharp, shooting, lancinating, shock like
pain, elicited by slight touching
superficial “trigger points” which radiate
from that point , across the distribution of
the one or more branches of the
trigeminal nerve.
13. CONT…
Pain is usually confined to one part of the one
division of TN- mandibular or maxillary, but
occasionally spreads to an adjacent division or
rarely involve all the three divisions.
Pain is of short duration and lasts for a few
seconds, but may recur with variable
frequency though there is a refractory period
(complete lack of pain) between the attacks,
some patients report of dull ache in between
the attacks.
14. Clinical features
Trigger points are stimulated either by touching or
chewing, smiling or speaking, brushing or shaving
or even washing the face.
Presence of an intraoral or extraoral trigger points
provocable by external stimuli is seen in TN.
Location of trigger points depends on the division
of the 5th cranial nerve
In V1 – supraorbital ridge of the affected side
in V2 –skin of the upper lip, ala nasi or cheek
or on the upper gums
In V3 - lower lip, teeth or gums of the lower
jaws .
15. Cont…
Paroxysmal Excruciating pain – stabbing,
severe, burning or shocking lasting for several
seconds.
Pain is associated with lacrimation, flushing
and salivation
Trigger zones (V3)– most common site-mental
foramen and maxillary canine region.
16. Cont….
Effected region is usually hyperkeratinised due
to vigorous rubbing
Rarely crosses the midline.
Does not occur during sleep
Paroxysms occur in cycles, each cycles lasting
for weeks or months. Pain seems to become
more intense and unbearable with each attack.
In extreme cases, the patient will have a
motionless face – frozen or mask like face.
17. Diagnosis
History (classic clinical pattern)
MRI scanning & CT.
Response to carbamazepine is universally
accepted by many clinicians as a step in
definitive diagnosis of the codition.
Diagnostic injections of a local anesthetic
agent into the patients trigger zone should
temporarily eliminate all the pain.
18. Protocol for diagnostic nerve blocks
Materials required
1cc syringe, 25 gauze needle, normal
saline, LA without adrenaline.
Always begin injections at the site of pain
and then move proximally.
Inject 0.5 ml of normal saline at test site.
wait for 5 min, if pain is relieved then
psychogenic pain is likely.
19. Cont….
If pain persists, the inject 0.5 ml of 2 %
lignocaine without adrenaline at surface site
and wait for 5 min, if pain is relieved then
direct therapy at small nociceptor fibres.
If pain persists, inject little deeper and wait for
5 min, if pain is relieved then consider
musculoskeletal origin of pain.
If pain is not relieved, inject more proximal
portion of nerve, if pain is relieved, direct
therapy at site.
20. Glossopharyngeal Neuralgia
Similar to trigeminal neuralgia
Rare
Pain related to sensory areas supplied
by pharyngeal and auricular branch of
vagus ( vagoglossopharyngeal
neuralgia)
Cause unknown
21. Clinical features :
Age : 15 – 85 (average 50)
No sex predilection
Paroxysmal pain in ear , infra auricular area,
tonsil , posterior mandible, lateral wall of
pharynx.
Difficulty in locating the pain
Episodic pain – unilateral , sharp,
lancinating, extremely intense.
22. Cont….
Abrupt onset
Short duration (30-60 secs) that repeats
for every 5 – 30 mins.
Talking , chewing , swelling, yawning,will
produce pain
Definite trigger zone easily identified.
23. Treatment
Unpredictable remissions and recurrence
80% of the patient has immediate pain relief
after the application of topical LA.
Drugs like carbemezipine, oxcarbazepine,
baclofen, phenytoin
Ressection of glossopharyngeal nerve
24. Sphenopalatine neuralgia
Otherwise called as Cluster Head ache
Pain affliction to middle face and upper
face.
Occurs as temporal groups or clusters
Cause – vascular (vasodiation) has been
suggested related to abnormal
hypothalamic function, head trauma,
abnormal release of histamine.
25. Cont…
Head ache is initiated by alcohol ,
cocaine and nitroglycerine .
80% of the patients are cigarette
smokers.
Clinical features
occurs at any age.
Sex predilection Male> Female
26. Cont…..
Pain is unilateral and follows the
distribution of ophthalmic division of
trigeminal nerve.
Pain felt behind the orbit , radiating to
temporal and upper cheek region.
Simulates tooth ache.
Pain is abrupt in onset , burning and
lancinating without trigger zones.
27. Cont…..
Pain lasts for 15 mins to 3 hrs. Eight
times daily or alternate days. And lasts
for week.
Pain often begins at same time at given
24 hr (alarm clock headache).
28. Treatment
Prednisone, ergotamine, lithium
carbonate, Indomethacin, verapamil.
Sumatriptan
New surgical tecniques have been
proposed.
(Gamma Knife Radiosurgery)