Facial Nerve Lesions, comprising lesions at different sites of the facial nerve and possible clinical manifestations.

1. Facial Nerve Lesions
Sameeullah Azeem
PG Anatomy 2nd Year
AIIMS Rishikesh

2. Contents
• Structure of Nerve
• Nerve Injury
• Causes and Types of Injury
• Localization
• Bells Palsy
• Crocodile tear syndrome
• Ramsay Hunt Syndrome
• Diagnostic Test
• Topodiagnostic Test

3. Structure of Nerve
Inside out
• Axon
• Myelin Sheath
• Neurolemma
• Endoneurium
• Perineurium
• Epineurium

4. Severity of Nerve Injury
• Degree of injury determines regeneration of
nerve & function
• Seddons Classification

5. Sunderland Classification

6. Sunderland Classification

7. Facial Nerve Disorders/Causes
Central
1. Brain Abscess
2. Pontine gliomas
Intracranial Part
1. Acaustic Neuroma
2. Meningioma
3. Congenital
Cholisteatoma
Extracranial Part
1. Malignency of Parotid
Gland
2. Surgery of Parotid Gland
3. Neonatal Facial Injury
Systemic Diseases
1. Diabetes Mellitus
2. Hypothyrodism
3. Uremia
4. Polyarthritis Nodosa

9. Types of Lesion
• A supranuclear lesion (i.e., in
hemiplegia) spares upper part of the
face because nuclear fibres
supplying muscles of upper part of
the face are innervated by
corticonuclear fibers of both
cerebral hemispheres.
• Only lower half of face on opposite
side is paralyzed.
• All infranuclear lesions involve
whole of face on same side.

10. Localisation of the Lesion
• If the Abducent & Facial nerve are not functioning
this suggests a lesion in Pons
• If Vestibulocochlear Nerve and Facial Nerve are not
functioning this suggests lesion in Internal Acoustic
Meatus
• Hyperacusis in one ear will occur if lesion involves
nerve to Stapedius in the Facial Canal

11. • Loss of taste over anterior 1/3rd of tongue suggests
lesion proximal to the point where it gives off Chorda
Tympani
• Swelling in the Parotid Gland associated with
impaired function of Facial Nerve suggests Cancer of
Parotid Gland

12. Bell’s Palsy
• Dysfunction of the facial
nerve within the facial canal
• Ipsilateral (Unilateral)
• The swelling of the nerve
fibres within the bony canal
results in temporary loss of
function producing lower
motor neuron type injury

13. Symptoms of Bells Plasy
1. Loss of wrinkles
2. Inability to close the eyes
3. Drooping of tears (Epiphora)
4. Loss of Nasolabial fold
5. Sagging of angle of mouth
6. Drooping of Saliva
7. Leaking of Air between lips
8. Trapping of food
9. Healthy side pulling the affected side

14. Crocodile Tears Syndrome
• Clinical condition
characterized by paroxysmal
lacrimation during eating.
• Results in the facial nerve
lesion proximal to the
geniculate ganglion
• Regenerating preganglionic
fibres meant to provide
secretomotor supply to the
submandibular and
sublingular salivary glands are
misdirected to Lacrimal Gland

15. Ramsay Hunt syndrome
• Occurs due to involvement of geniculate ganglion
in herpes zoster infection.
• Clinically it presents with
1. Herpetic vesicles on the auricle.
2. Hyperacusis.
3. Loss of lacrimation.
4. Loss of taste sensations in the anterior two-third
of the tongue.
5. Complete ipsilateral facial palsy (Bell’s palsy).

16. Diagnostic Tests
Minimal Nerve Excitability Test
• Nerve is stimulated at steadily
increasing intensity till facial
twitch is noticeable.
• This is compared with normal side.
• When difference between two
sides increase 3.5 miliampere,
test is positive for degeneration

17. • Maximal Stimulation Test
• Similar to minimal nerve exitibality test but instead
of measuring threshold of stimulation, the current
level which gives maximum facial moment is
determined and compared with normal side.
• Reduced or absent response with maximal
stimulation indicates degeneration

18. • Electromyography
• This tests the motor activity
of facial muscles by insertion
of needle electrodes into
orbicularis oris and oculi and
recordings are made
• I normal resting muscle,
biphasic or triphasic
potentials are seen every
30-50 milliseconds
• In denervated muscle
spontaneous activity
Fibrillations are seen

19. Topodiagnostic Tests of Lesions
Schiemers Test
• It compares lacrimation of
two sides
• A strip of filter paper is
hooked in the lower fornix of
each eye and amount of
wetting of strip
• Decreased lacrimation
indicates lesion proximal to
geniculate ganglion

20. Stapedial Reflex
• Lost in lesions above the nerve
to stapedius
• Tested by Tympanometry
• Stapedial reflex in Bells Palsy
Gives better prognosis

21. Taste Test
• Its measured by dropping salt
or sugar solution on one side
of the protruded tongue or by
electrogustrometry
• Impairment of taste indicates
lesion above chorda tympani

22. Submandibular Salivary Flow
• Measures function of
Chorda Tympani
• Polythene tubes are passed
into Wartons ducts and
drops of saliva are counted
during one minute
• Decreased salivation shows
injury above chorda
tympani

23. Questions

24. MCQs
• Q.1) If a patient comes in clinical setting with
weakness of one side of face & there is
hyperacusis, then which cranial nerves injury is
involved?
A) 6th & 7th
B) 7th & 8th
C) 5th & 7th
D) 7th & 9th
Ans. B

25. MCQs
• Q.2) In intracranial course facial nerve gives
its branch to which muscle?
• A) Stapedius
• B) Tensor tympani
• C) Temporalis
• D) Zygomaticus major
• Ans. A

26. MCQs
• Q.3)More chances of nerve regeneration are
present in which type of nerve injury?
A) Neurotemesis > Neuroprexia> Axontemesis
B) Neuroprexia> Neurptemesis>Axontemesis
C) Neuroprexia>Axontemesis>Neurotemesis
D) Axontemesis>Neurotemesis>Neuroprexia
• Ans.C

27. MCQs
• Q.4) If there is difficulting in lateral eyeball
movement associated with facial nerve injury
symptoms , then at which level facial nerve is
affected?
A) At pons level
B) At pontomedullary junction
C) In internal ear
D) At parotid gland
• Ans. A

28. Thank You