This document provides an overview of the facial nerve (cranial nerve VII) including its embryological development, intra-cranial and extra-cranial course, branches, and variations. The facial nerve originates in the brainstem and controls muscles of facial expression and carries taste sensation from the anterior two-thirds of the tongue. It has both motor and sensory components. The document describes the facial nerve's path through the skull and middle ear before exiting to innervate muscles of the face and neck. It discusses ganglia and branches associated with the facial nerve. Variations in its branching patterns are also summarized.

1. FACIAL NERVE
Prepared By –
Meenal Nikhar

2. CONTENTS
Introduction to facial nerve
Embryological aspects
Intra Cranial course and supply
Extra Cranial course and supply
Variations in facial nerve anatomy

3. INTRODUCTION
 VIIth Cranial Nerve
 Mixed Nerve
 It emerges from Brain Stem between Pons and Medulla.
 Controls Muscles of Facial Expression and carry taste
sensation

4. EMBRYOLOGY
 Derived from Hyoid Arch (Second Branchial Arch)
 Motor division – Basal Plate of the Embryonic Pons
 Sensory division – Cranial Neural Crest
 First identification of Facial Nerve – 3rd week of Gestation
– Fascioacoustic Primordium or Crest
 Course, Branching Pattern, Anatomic relationship – First 3rd
month of Prenatal Life
 Not fully developed until 4 years of age

5. EMBRYOLOGY
4th Week 5th Week 6th Week

6. NUCLEI OF ORIGIN
Facial Nerve Proper – It lies in the
Pons
 Nucleus Intermedius – It lies in the
lower part of the Pons
Nucleus Solitarus- It lies in the
Medulla
Superior Salivatory Nucleus – I t lies
below the Motor Nucleus

7. COURSE OF FACIAL NERVE
FACIAL NERVE
INTRA CRANIAL
COURSE
INTRA
TEMPORAL
COURSE
EXTRA
CRANIAL
COURSE

8. INTRA CRANIAL COURSE OF FACIAL
NERVE
 The nerve passes Laterally with the Vestibulocochlear nerve to the
Internal Auditary Meatus. At the bottom of meatus, nerve enters the
Facial Bony Canal where it runs laterally above the vestibule of inner
ear.
 Reaching the medial wall of the middle ear, it bends sharply
backwards above forming its Genu where the Genicular Ganglion is
found
 It then arches downwards in the medial wall of the middle ear to reach
the Stylomastoid Foramen.

9. INTRA CRANIAL COURSE OF FACIAL
NERVE
FACIAL
NERVE
Greater
Petrosal
Nerve
Nerve to
Stapaedius
Chorda
Tympani

10. INTRA CRANIAL COURSE OF FACIAL NERVE

11. INTRA CRANIAL COURSE OF FACIAL NERVE
 Greater Petrosal Nerve –
It originates from Geniculate Ganglion and forms the Nerve of Pterygoid Canal and
reaches to Pterygoid fossa and ends in Pterygopalatine Ganglion
 Nerve to Stapaedius –
It gives supplies to Stapaedius Muscle
 Chorda Tympani –
It arises from 6 mm above Stylomastoid Foramen and perforates the posterior wall of
Tympanic cavity, comes out of Pterygotympanic Fossa and joins to Lingual Nerve

12. INTRA CRANIAL COURSE OF FACIAL NERVE

13. INTRA TEMPORAL COURSE OF FACIAL
NERVEIntra Meatal –
Accompanied by VIIIth Cranial Nerve, it passes through Internal
Auditory canal to Fundus. Leaving Meatus through Meatal Foramen
Labyrinthine –
After running to short distance anteriorly, it gives off the greater
petrosal nerve to the lacrimal and nasal glands. It turns sharply
downward and posteriorly at geniculate ganglion, forming the first Genu

14. INTRA TEMPORAL COURSE OF FACIAL
NERVE
Tympanic –
It runs horizontally through middle ear, passing above the Stapes, to
the aditus ad antrum near the lateral semicircular canal giving of Mastoid
Nerve
Mastoid Nerve –
It forms The Second Genu by the aditus ad antrum, turning vertically
downward [approx. 90ᶱ angle].
Later it leaves bony canal at the stylomastoid foramen. Just before
exiting through foramen, facial nerve gives off the Chorda Tympani

15. SEGMENTAL DISCRIPTION OF FACIAL NERVE
SEGMENTS LOCATION LENGTH [mm]
SUPRA NUCLEAR CEREBRAL CORTEX NA
BRAIN STEM MOTOR NUCLEUS OF FACIAL NERVE,
SUPERIOR SALIVATORY NUCLEUS OF
TRACTUS SOLITARIUS
NA
MEATAL SEGMENTS BRAINSTEM TO INTERNAL ACOUSTIC
MEATUS OR CANAL (IAC)
13 – 15
LABYRINTHINE SEGMENT FUNDUS OF IAC TO THE FACIAL HIATUS 3 – 4
TYMPANIC SEGMENTG GENICULATE GANGLION TO PYRAMIDAL
EMINENCE
8 – 11
MASTOID SEGMENT PYRAMIDAL EMINENCE TO
STYLOMASTOID FORAMEN
10 – 14
EXTRA TEMPORAL
SEGMENT
STYLOMASTOID FORAMEN TO PES
ANSERINUS
15 - 20

16. GANGLION ASSOCIATED WITH FACIAL
NERVE
Geniculate Ganglion
Submandibular Ganglion
Pterygopalatine Ganglion

17. GENICULATE GANGLION
An L-shaped collection of fibers
and Sensory Neurons located in
the facial canal of the head.
 It receives fibers from the motor,
sensory, and parasympathetic
components and sends fibers,
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.

18. SUBMANDIBULAR GANGLION
It is small and fusiform in shape,
situated above the deep portion of the
Submandibular Gland, on the
Hyoglossus Muscle, near the posterior
border of Mylohyoid Muscle.
The ganglion 'Hangs' By Two Nerve
Filaments from the lower border of the
lingual nerve, One Anterior and One
Posterior.
The Posterior of these it receives a
branch from the Chorda Tympani
Nerve runs in the sheath of the lingual
nerve.

19. PTERYGOPALATINE GANGLION
It is a parasympathetic ganglion
found in the Pterygopalatine
Fossa.
It's largely innervated by The
Greater Petrosal Nerve and is
projected to the Lacrimal Glands
and Nasal Mucosa

20. EXTRA CRANIAL COURSE OF FACIAL
NERVE
EXTRA
CRANIAL
COURSE
POSTERIOR
AURICULAR
NERVE
DIAGASTRIC
NERVE
STYLOHYOID
NERVE

21. EXTRA CRANIAL COURSE OF FACIAL
NERVE

22. EXTRA CRANIAL COURSE OF FACIAL NERVE
 Posterior Auricular Nerve –
To the auricularis posterior and the occipital belly of the
occipitofrontalis muscle.
 Digastric Nerve –
To the posterior belly of digastric muscle.
 Stylohyoid Nerve –
To the stylohyoid muscle

23. BRANCHES ARE CLASSIFIED AS
BRANCHES
BRANCHES OF
COMMUNICATION
BRANCHES OF
DISTRIBUTION

24. BRANCHES OF COMMUNICATION
Internal Acoustic Meatus Vestibulocochlear Nerve
Geniculate Ganglion A. Greater Petrosal Nerve
B. Lesser Petrosal Nerve
C. External Petrosal Nerve
Facial Canal Vagus Nerve
Stylomastoid Foramen IX & X Cranial Nerve
Greater Auricular Nerve
Auriculotemporal Nerve
Behind Ear Lesser Occipital
Face V Nerve
Neck Transverse Cutaneous Nerve

25. BRANCHES OF DISTRIBUTION
Facial Canal
• Nerve Of
Stapedius
• Chorda Tympani
Stylomastoid
Foramen
• Posterior
Auricular
• Nerve to
Stylohyoid
• Nerve to
Digastric
In Face
• Temporal
• Zygomatic
• Buccal
• Marginal
Mandibular
• Cervical

26. TERMINAL BRANCHES OF FACIAL NERVE

27. TERMINAL BRANCHES OF FACIAL NERVE

28. TERMINAL BRANCHES
• Temporal Branch –
It crosses zygomatic arch to the temporal region, supplying
Auricularis Anterior and Superior, and join with the
Zygomaticotemporal branch of the maxillary nerve, and with the
Auriculotemporal branch of the mandibular nerve.
 Zygomatic Branch –
It run across the zygomatic bone to lateral angle of the orbit,
supplying the Orbicularis Oculi, and join with the Lacrimal nerve
and the Zygomaticofacial branch of the maxillary nerve.

29. TERMINAL BRANCHES
 Buccal Branch –
It is largest than the rest of the branches, distributed below the
orbit and around the mouth.
MUSCLE ACTION
Risorius Smile
Buccinator Aids chewing by holding cheeks flat
Levator Labii Superioris Elevates upper lip
Levator labii superioris alaeque nasi Snarl
Levator Anguli Oris Soft smile
Nasalis Flare Nostrils
Orbicularis oris muscle Purse Lips
Depressor Septi Nasi Depresses Nasal Septum
Procerus Moves Skin of Forehead

30. TERMINAL BRANCHES
 Mandibular Branch –
It passes forward beneath the Platysma and Depressor
Anguli Oris, supplying the muscles of Lower Lip and Chin, and
communicating with Mental Branch Of The Inferior Alveolar
Nerve.
 Cervical Branch –
It forms a series of arches across the side of the neck over
the Suprahyoid Region. One branch descends to join The
Cervical Cutaneous Nerve from the cervical plexus; others supply
the Platysma. It also supplies the Depressor Anguli Oris.

31. FUNCTIONAL COMPONENT OF FACIAL NERVE
Special Visceral Efferent Branchial Motor
General Visceral Efferent Parasympathetic
General Sensory Afferent Sensory
Special Visceral Afferent Taste

32. SPECIAL VISCERAL EFFERENT
 Premotor cortex
 Motor cortex
 Corticobulbar tract
 Bilateral Facial motor nuclei (pons)
 Facial Muscles
 Stapedius, Stylohyoid, Posterior Digastric, Buccinator

33. GENERAL VISCERAL EFFERENT
Superior Salivatory Nucleus (Pons)
Nervus Intermedius
Greater/Superficial Petrosal Nerve
Facial Hiatus/Middle Cranial Fossa
Joins Deep Petrosal Nerve (Symp Fibers From Cervical Plexus)
Through Pterygoid Canal (As Vidian Nerve)
Pterygopalatine Fossa
Spheno/Pterygopalatine Ganglion
Postganglionic Parasympathetic Fibers
Joins Zygomaticotemporal Nerve(v2)
Lacrimal Gland & Seromucinous Glands Of Nasal And Oral Cavity

34. GENERAL VISCERAL EFFERENT
Superior Salivatory Nucleus
Nervus Intermedius
Chorda Tympani
Joins Lingual Nerve
Submandibular Ganglion
Postganglionic Parasympathteic Fibers
Submandibular And Sublingual Glands

35. GENERAL SENSORY AFFERENT
Sensation to Auricular Concha, EAC Wall, Part Of TMJ,
Postauricular Skin
Through Cell bodies in Geniculate Ganglion

36. SPECIAL VISCERAL AFFERENT
Postcentral Gyrus
Nucleus Tractus Solitarius
Nervus Intermedius
Geniculate Ganglion
Chorda Tympani
Joins Lingual Nerve
Anterior 2/3rd Tongue, Soft And Hard Palate

37. VARIATION OF FACIAL NERVE
Buccal Branch usually single, two branches in 15% cases
Marginal Mandibular Branch – pass bellow the lower border of
mandible, incidence varying between 20-50%
Cervical branch – Two branches in 20% cases,
Katz and Catalano reported 3% cases presenting two main trunks,
known as the major and minor trunks of facial nerve.
Baker and Conley reported trifurcation, quadrifurcation, or even a
plexiform branching pattern of the trunk of the facial nerve

38. PATTERNS OF FACIAL NERVE
Classified by Davis et al (1956)
1) Type I facial nerve with Straight Branching along Variations
2) Type II facial nerve Major Connection Between Buccal &
Zygomatic Nerves
3) Type III facial nerve with Major Connection Between Buccal &
Any Other Nerve
4) Type IV Complex branching pattern
5) Type V Two main trunks

39. PATTERNS OF FACIAL NERVE
Type I facial nerve with Straight Branching along Variations
 TYPE IA
I. Zygomatic branch with a loop
sending to itself
II. No loop with Zygomatic branch
 TYPE IB
I. Marginal Mandibular branch with a
loop sending to itself
II. No loop with Marginal Mandibular
Nerve

40. PATTERNS OF FACIAL NERVE
Type II facial nerve Major Connection Between Buccal &
Zygomatic Nerves

41. PATTERNS OF FACIAL NERVE
Type III facial nerve with Major Connection Between Buccal & Any
Other Nerve
Type IIIA
i). Anastomosis between Zygomatic & Buccal nerve
ii). Anastomosis between Buccal & Upper Division
iii). Anastomosis between Buccal and Lower Division
Type IIIB
iv). Anastomosis between Buccal Nerve & Zygomatic Nerve
Type IIIC
v) Connection between Buccal & Marginal Mandibular Nerve
vi). Connection between Buccal Nerve arising from upper division &
lower division .
vii). Additional anastomosis between upper & lower divisions .

42. Type III facial nerve with Major Connection Between
Buccal & Any Other Nerve

43. PATTERNS OF FACIAL NERVE
Type IV Complex branching pattern
 Type IVA
I. Buccal nerve arising from Lower
division with anastomosis present
with upper division
II. Anastomosis between buccal nerve
& upper division
 Type IVB
I. Buccal nerve arising from both
division with Anastomosis
II. Buccal nerve arising from upper
division only

44. PATTERNS OF FACIAL NERVE
Type V Two Main Trunks
Type VA
Upper & Lower division arising from major trunk, Buccal nerve arises
from both divisions, Minor trunk joins Lower division.
Type VB
Upper division from major & lower from Minor trunk, Buccal nerve
arises from both division.
Type VC
Upper & Lower division both arise from the Major trunk & minor trunk
enters the upper division as a separate branch.

45. Type V Two Main Trunks

46. THANK YOU