The document discusses the facial nerve (cranial nerve VII). It begins by classifying it as a mixed nerve that is predominantly motor and supplies the muscles of facial expression. It then covers the functional components and nuclei of the nerve, its intracranial and extracranial courses through various canals and foramina, its branches and distribution to various structures like the lacrimal gland and muscles of facial expression, clinical tests of its function, and applied aspects like Bell's palsy and Ramsay Hunt syndrome.

2. FACIAL NERVE
GUIDED BY PRESENTED BY
DR. SHALU RAI - DR. PRIYANKA
DR. DEEPANKAR MISRA
DR. SAHIL KIDWAI
DR. SUMAN BISLA

3. CLASSIFICATION ( BASED ON FUNCTION )
SENSORY CRANIAL NERVE
( FROM STIMULI TO CNS
)
OLFACTORY NERVE (I)
OPTIC NERVE (II)
VESTIBULOCOCHLEAR NERVE
(VIII)
MIXED NERVE
TRIGEMINAL NERVE (V)
FACIAL NERVE (VII)
GLOSSOPHARYNGEAL NERVE
(IX)
VAGUS NERVE (X)
MOTOR CRANIAL NERVE
(FROM CNS TO TARGET
ORGANS)
OCCULOMOTOR NERVE (III)
TROCHLEAR NERVE (IV)
ABDUCENT NERVE (VI)
ACCESSORY NERVE (XI)
HYPOGLOSSAL NERVE (XII)

4. CONTENTS
 Introduction
 Functional Component and Nuclei
 Courses And Relation
 Branches And Distribution
 Clinical Test
 Ganglions
 Blood supply
 Applied Aspect

5. INTRODUCTION
 7thcranialnerve
 mixed nerve( predominantlymotor )
 named asfacialnerve– supplymuscles offacialexpression
 Mostfrequentlyparalyzednerve
 Nerveof secondbranchialarch
 Arisefromthebrainstem
 extendposteriorlyto abducentN
anteriorlyto vestibulocochlearN
DulakD, NaqviIA. Neuroanatomy,CranialNerve7 (Facial)[Updated2020Nov29]. In:StatPearls[Internet].
TreasureIsland(FL):StatPearlsPublishing;2020Jan

6. FUNCTIONAL COMPONENTS
 SPECIAL VISCERAL EFFERENT FIBRES ( SVE / BRANCHIOMOTOR FIBERS )
 arise form motor nucleus of facial nerve in lower part of pons
 supply muscles of facial expression , stapedius, stylohyoid muscle, posterior belly of digastric muscle.
 Major component
 GENERAL VISCERAL EFFERENT FIBRES / VISCERAL MOTOR FIBRES
 preganglionic parasympathetic fibres
 arise from lacrimatory and superior salivatory nuclei , lateral to motor nucleus
 Fibres run in greater petrosal N and N of pterygoid canal and synapse in pterygopalatine ganglion
 Supply to submandibular , sublingual gland, lacrimal gland , nasopharynx and palate

7.  SPECIAL VISCERAL AFFERENT FIBRES / SPECIAL SENSORY
 carry taste sensation from anterior 2/3 rd of tongue, enter into middle ear from internal auditory meatus
and terminate into nucleus of tractus solitarius in medulla (brainstem)
 GENERAL VISCERAL AFFERENT FIBRE
 Afferent impulse from submandibular, and sublingual glands , lacrimal glands and glands of nose,
palate and pharynx
 GENERAL SOMATIC AFFERENT FIBERS
 carry general sensation ( touch, pain & temperature )from external ear
 terminate in spinal nucleus of trigeminal nerve
GVE+ SVA + GSA = NERVUS INTERMEDIUS
BRANCHIOMOTOR = FACIAL N PROPER

8. NUCLEI
 MOTOR NUCLEUS
 located in lower part of pons , medial to spinal trigeminal nucleus
also k/n as BRANCHIOMOTOR NUCLEUS ( its efferent supply the muscle – 2nd pharyngeal
arch)
 Migration of this nucleus during development, result in looping of its fibre within brainstem.
 Provides the efferent component of reflexes initiated by stimulation of other sensory cranial nerves
Facial Nerve review article by Kojiro takezawa et al, 2017

9.  PARASYMPATHETIC ( SUPERIOR SALIVATORY ) NUCLEUS
 Location - pons
 Provide preganglionic nerve fibres forming the general visceral efferent component , exit pons in
nervus intermedius
 GUSTATORY ( SOLITARY ) NUCLEUS
Location – lateral part of medulla oblongata
Nucleus is shared among facial N , glossopharyngeal Nerve and Vagus Nerve
 SPINAL NUCLEUS
 Receive small number of sensory fibres, via communication with auricular branch of Vagus Nerve
 Fibers don’t loop around Abducens nucleus
Facial Nerve review article by Kojiro takezawa et al, 2017

11. COUSES AND RELATION
 INTRACRANIAL COURSE
 EXTRACRANIAL COURSE
Vishram singh 2nd edition

14. INTRACRANIAL COURSE
 Facial N is attached to the brainstem by two roots : 1. Motor root ( facial N proper )
2. Sensory root ( nervous intermedius )
 two roots arise from – pontomedullary junction / pontocerebellar junction
 Both roots are medial to 8th cranial N

15.  after emerging from brainstem ( pontomedullary junction )
root of facial N + vestibulocochlear N + Labyrinthine A
internal acoustic meatus
branchiomotor fibres+ salivatory fibres + sensory fibres enter into
geniculate ganglion
( sensory root remain separated )
facial canal

16. facial canal is divided into
1. labyrinthine
2. tympanic
3. mastoid
1. LABYRINTHINE
arise from geniculate ganglion and run anterosuperior part of medial wall of middle ear
2. TYMPANIC
run horizontally backward in medial wall of middle ear till it reaches junction of medial and
posterior wall of middle ear
3. MASTOID
begin at junction of medial and posterior wall and runs vertically downward in posterior wall till it
reaches stylomastoid foramen

17. facial canal (branchiomotor fibres+ salivatory fibres + sensory fibres )
branchiomotor fibre – accessory N ( n to stapedius )
- exit from stylomastoid foramen
– post auricle, stylohyoid muscle & post belly of digastric muscle
salivatory fibres – exit from facial canal 6mm above to stylomastoid foramen - salivary gland
sensory fibres – tractus solitarius - anterior 2/3rd of tongue ( taste sensation ) &
- spinal nucleus of trigeminal nerve - external ear ( touch, pain & temperature)
- lateral to lingual N of mand div of 5th N

19. lacrimatory fibres – greater petrosal N ( middle cranial fossa )
foramen lacerum
sympathic fiber ( internal carotid A ) + lacrimatory fiber
pterygoid canal ptrygopalatine ganglion
( post ganglionic parasympathetic fibres )
lateral to zygomatic branch of max div of 5th N
lacrimal gland

20. BRANCHES AND DISTRIBUTION
 WITHIN FACIAL CANAL
1. GREATER PETROSAL NERVE
 arise from geniculate ganglion – middle cranial fossa – foramen lacerum – n to pterygoid canal-
pterygopalatine ganglion
 consist of preganglionic parasympathetic fibres ( sup salivatory nucleus ) – relay in
pterygopalatine ganglion – supply lacrimal gland, mucous gland of nasal cavity and palate
Vishram Singh 2nd edition

21. 2. NERVE TO STAPEDIUS
arise from vertical part of canal and carry branchiomotor fibers and exit to supply stapedius muscle
3. CHORDA TYMPANI NERVE
 arise from vertical part of facial N , 6mm above stylomastoid foramen , enter middle ear , run across lateral
wall and leave it on anterior wall
 join posterior aspect of lingual N and supply submandibular and sublingual gland and carry taste sensation
from ant 2/3rd of tongue
Vishram Singh 2nd edition

22.  AT ITS EXIT FROM STYLOMASTOID FORAMEN
1. POSTERIOR AURICULAR NERVE
 just above stylomastoid foramen & communicate with auricular branch of vagus N and convey
sensory fiber from external auditory meatus
 supply occipitallis
2. N TO POSTERIOR BELLY OF DIGASTRIC
exit from foramen , supply digastric muscle
3. N TO STYLOHYOID MUSCLE
supply stylohyoid muscle
Vishram Singh 2nd edition

23.  TERMINAL BRANCHES
cross styloid process and enter posteromedial surface of parotid gland
1. TEMPORAL – auricularis, frontalis, orbicularis oculi
2. ZYGOMATIC - orbicularis oculi, nose and upper lip
3. BUCCAL - buccinator and upper labial muscle
4. MARGINAL MANDIBULAR – muscle of lower lip and chin
5. CERVICAL – platysma
Supply muscle of facial expression
Vishram Singh 2nd edition

24. CLINICAL TEST
 Anterior 2/3rd of tongue – sugar, salt
 tear gland – schemer’s test
 motor function – close eyes, smile , whistle , raise eyebrows ( blink, nasolabial fold and corners of
mouth)
Testing of Facial Nerve Branches
temporal branches of the facial nerve – patient is asked to frown and wrinkle his or her forehead.
Zygomatic branches of the facial nerve patient is asked to close their eyes tightly
buccal branches of the facial nerve • Puff up cheeks (buccinator)
• Smile and show teeth (orbicularis oris)

25. GENICULATE GANGLION
 The geniculate ganglion (from Latin genu, for "knee") is an L- shaped collection of fibers and
sensory neurons of the facial nerve located in the facial canal of the head.
 It receives fibers from the motor, sensory, and parasympathetic components of the facial nerve and
sends fibers that will innervate the lacrimal glands, submandibular glands, sublingual glands,
tongue, palate, pharynx, external auditory meatus, stapedius, posterior belly of the digastric
muscle, stylohyoid muscle, and muscles of facial expression.

26. SUBMANDIBULAR GANGLION
 small and fusiform in shape.
 situated above the deep portion of the submandibular gland, on the hyoglossus muscle, near the
posterior border of the mylohyoid muscle.
 It has sensory, sympathetic and secretomotor fibres

27. PTERYGOPALATINE GANGLION
 The pterygopalatine ganglion is a parasympathetic ganglion found in the pterygopalatine fossa.
 It is called the ganglion of hay fever
 suspended by maxillary nerve , functionally it is related to facial nerve
It has sensory, sympathetic and secretomotor roots
 It's largely innervated by the greater petrosal nerve (a branch of the facial nerve); and its axons
project to the lacrimal glands and nasal mucosa

28. BLOOD SUPPLY
 Anterior inferior cerebellar artery – at cerebellopontine angle
 Labyrinthine artery (branch of anterior inferior cerebellar artery) – within internal acoustic
meatus
 Superficial petrosal artery (branch of middle meningeal artery) – geniculate ganglion and nearby
parts
 Stylomastoid artery (branch of posterior auricular artery) – mastoid segment
 Posterior auricular artery supplies the facial nerve at & distal to stylomastoid foramen

29. APPLIED ASPECT
 INJURY TO STAPEDIUS – normal sound appear too loud ( hyperacusis), loss of taste and palsy
without loss of tears
 INJURY TO ZYGOMATIC – prevent blinking
 INJURY TO BUCCAL BRANCH – dribbling from mouth
 INJURY TO MARGINAL MANDIBULAR – paralysis of depressor of lower lip
 BELL’S PALSY – sudden paralysis of N at stylomastoid foramen, result in asymmetry of corner
of mouth
- Pain on affected side
- Inability to close eye ( watering of eye – infection )
- disappearance of nasolabial fold
- loss of wrinkling of skin of forehead on same side

30. - speech and eating –difficult
- Taste sensation – anterior portion – lost or altered
- retained food in buccal fold due to weakness of buccinator
- ASSOCIATED SYNDROME – MELKERSON ROSENTHAL SYNDROME
- TREATMENT PLAN
- VASODILATOR
- surgical decompression and anastomosis of nerve
- steroid

31.  LESION ABOVE ORIGIN OF CHORDA TYMPANI – symptom of bell’s palsy with loss of taste from ant 2/3rd of tongue
 CROCODILE TEAR SYNDROME - paroxysmal lacrimation during eating because of aberrant regeneration after trauma
- Injury proximal to geniculate ganglion, regenerating fibers for submandibular gland
- 6-9 months after bells palsy
- Botulinum inj ( acetylcholine release inhibitor )
 RAMSAY HUNT SYNDROME - involvement of geniculate ganglion in herpes zoster infection
- herpetic vesicle on auricle
- Hyperacusis
- loss of lacrimation
- loss of taste sensation in ant 2/3rd of tongue
- Vesicular eruption in oral cavity and oropharynx
- bell’s palsy
 FACIAL N INJURIES IN BABIES- birth injury or trauma ( sucking problem )

32.  GENICULATE NEURALGIA - zoster infection
- f>m
- Pain in ear, soft palate and tongue
- Trigger zone – ear
- Vesicles in ear
- Management- steroid , acyclovir , carbamazepine
TRANSIENT FACIAL PALSY
- On inferior alveolar nerve injection

33.  FACIAL PALSY
TYPES- upper motor neuron and lower motor neuron facial palsy
UPPER MOTOR NEURON FACIAL PALSY
- Due to involvement of cortico nuclear fibers (upper motor neuron )
- These fibers arise in cerebral cortex- internal capsule – end in motor nucleus of facial N
- Most commonly involved in pts with cerebral hemorrhage associated with hemiplegia
- Since lesion is above nucleus – supranuclear type of facial palsy
- Leads to paralysis of contralateral lower part of face below palpebral fissure

34.  LOWER MOTOR NUCLEUS FACIAL PALSY
TYPES- 1. nuclear paralysis
- Due to involvement of nucleus of facial N
- Occur due to poliomyelitis or lesion of pons
- Motor nucleus is close to abducent nucleus so it is usually affected
- Paralise the muscle of entire face on ipsilateral side
2. Infranuclear paralysis
- Due to involvement of facial N
- Clinical effect according to site of injury of N

35. site A – At or just above stylomastoid foramen
- Leads to bell’s palsy ( deviation of mouth toward normal side, inability to close mouth and eye
accumulation of food in vestibule etc)
Site B – above origin of chorda tympani
- All sign and symptoms of lesion A along with decreased salivation and loss of taste sensation in ant
2/3 rd of tongue
Site C – above origin of N to stapedius
- All signs and syptoms of lesion B along with hyperacusis
Site D – At geniculate ganglion
- all sign and symptoms of lesion C along with lacrimation

36. This Photo by Unknown Author is licensed under CC BY-NC-ND