The cranial nerves IX, X, and XI were summarized. The glossopharyngeal nerve (CN IX) emerges from the medulla and has sensory and motor branches that innervate structures in the pharynx, tongue, and carotid body. The vagus nerve (CN X) is a mixed nerve with extensive distribution from the head and neck to the abdomen. It emerges from the medulla and has branches throughout its course. The accessory nerve (CN XI) has a cranial and spinal root, with the spinal root innervating the sternocleidomastoid and trapezius muscles.

1. CRANIAL NERVES
(IX, X, XI)
BY DR. PIYUSH

8. GLOSSOPHARYNGEAL NERVE
(Cranial Nerve IX)

9. INTRODUCTION
• Mixed Nerve
• Emerges from posterolateral
sulcus of Medulla Oblongata.

13. Functional component
FN COMP. NUCLEUS target origin
SVE
(BRANCHIOMOTOR)
nucleus
ambiguus
stylopharyngeus -
GVE
(SECRETOMOTOR)
Inf. Salivatory Parotid -
GSA
(SOMATOSENSORY)
spinal nucleus of
Vth nerve
-
Post 1/3rd tongue,tonsil, soft
palate & oropharynx
SVA
(GUSTATORY)
nucleus tractus
solitarius
-
Circumvalate papillae & Post
1/3rd tongue
GVA
(VISCEROSENSORY)
nucleus tractus
solitarius
-
Baro & chemoreceptors from
carotid sinus and body.

14. Course
• Arises from posterolateral sulcus of medulla in the form of 3-4 rootlets.
• In the jugular foramen combine to form nerve trunk.
• Trunk has 2 ganglion : superior & inferior
• leaves skull through intermediate compartment of Jugular foramen
• Passes between IJV and ICA
• Passes between ICA and ECA
• Deep to styloid process
• enters pharynx between superior and middle constrictor.

20. Branches
• Communicating branches with
• Superior cervical sympathetic ganglia
• superior and inferior ganglia of vagus
• facial nerve

21. To Vagus

22. • Distributing Branches: 6 sets of branches
• Tympanic branch: (secretomotor) preganglionic
parasympathetic fibres- tympanic plexus- lesser
petrosal nerve- otic ganglion- post ganglionic
fibres- via Auriculotemporal nerve - parotid gland.

25. • Carotid branch: (viscerosensory) carotid sinus and
carotid body
• Pharyngeal branches- (somatosensory) 3-4; ramify
over buccopharyngeal fascia over middle constrictor
and with vagus and superior sympathetic ganglion
branches forms the pharyngeal plexus.

26. • Muscular branch: (Branchiomotor): to stylopharyngeus
• Tonsillar branches: (somatosensory) tonsilar plexus with
middle and lesser palatine nerves
• Lingual branches: (somatosensory & gustatory) post
1/3rd tongue and valate papilla.

27. Applied
• Isolated injury is rare
• Cardiac arrest or syncope after bout of cough:
increased pressure in carotid sinus, sinus branch of IX th
nerve reflexly stimulates cardio inhibitory centres of brain
stem.

28. Vagus Nerve
(Cranial nerve X)

29. INTRODUCTION
• Mixed Nerve
• extensive distribution from head & neck to abdomen
therefore called Wandering nerve.
• Emerges from posterolateral sulcus of Medulla Oblongata
below IXth nerve.

31. Functional component
FN COMP. NUCLEUS target origin
SVE
(BRANCHIOMOTOR)
nucleus ambiguus Muscles of Pharynx & larynx
GVE
(VISCEROMOTOR)
Dorsal nucleus of
vagus
Heart, smooth muscles and
glands of respiratory tract,
alimentary trac proximal 2/3rd and
distaLal 1/3rd of transverse colon
GVA
(VISCEROSENSORY)
Dorsal nucleus of
vagus & NTS
Heart, smooth muscles and
glands of respiratory tract,
alimentary trac proximal
2/3rd and distaLal 1/3rd of
transverse colon
GSA
(SOMATOSENSORY)
upper part of spinal
nucleus of Vth nerve
External auditory canal &
tympanic membrane
SVA
(GUSTATORY)
nucleus tractus
solitarius
vallecula & pyriform fossa

33. Course
• 4 parts: Cervical; thoracic & abdominal
• Arises from posterolateral sulcus of medulla in the form of
>10 rootlets.
• In the jugular foramen combine to form nerve trunk.
• In Cervical region:
• leaves skull through intermediate compartment of
Jugular foramen
• descends in carotid sheath

39. • Between & behind IJV & CCA or ICA
• Trunk has 2 ganglion :
• superior (jugular) : pseudounipolar sensory neurons
for GSA
• inferior (nodose): pseudounipolar sensory neurons
for GVA & SVA

42. • In Thorax:
• Right vagus: passes behind the lung root and contributes in the
formation of right posterior pulmonary plexus; posterior part of
oesophageal plexus and finally enters the abdomen as posterior
vagal trunk.
• Left Vagus: passes behind the lung root and contributes in the
formation of left posterior pulmonary plexus; Anterior part of
oesophageal plexus and finally enters the abdomen as Anterior
vagal trunk.

44. • In Abdomen:
• Anterior vagal trunk:1-3 bundles; each branch divide
into hepatic and gastric branches ; supply upto
duodenum.
• Posterior vagal trunk: gastric and coeliac branches ;
supply upto transverse colon (junction of proximal 2/3rd
and distal 1/3rd)

46. Branches
• In Neck:
• from superior ganglion
• Meningeal branch: (Somatosensory) Dura of posterior
cranial fossa
• Auricular branch (Alderman’s nerve): (Somatosensory)
Auricle, floor & posterior wall of external auditory canal
and adjoining tympanic nerve

47. • From Inferior ganglion
• Pharyngeal branches
• Superior laryngeal nerve
• branches to the carotid body
• From the trunk:
• Cardiac branches
• Right recurrent laryngeal nerve

48. • In the thorax:
• Left recurrent laryngeal nerve
• Pulmonary branches
• Cardiac branches
• Oesophageal branches

49. • In the Abdomen:
• Gastric branches
• Hepatic branches
• Coeliac branches

50. Applied
• Auricular branch irritation may lead to vomitting or even
precipitate cardiac arrest.
• Recurrent laryngeal nerve injury during thyroid surgery
• Selective vagotomy for peptic ulcer.

51. Accessory Nerve
(Cranial nerve XI)

52. INTRODUCTION
• Motor Nerve
• Emerges from posterolateral sulcus of Medulla Oblongata
below vagus.
• 2 roots :
• Cranial: detached rootlet of vagus
• Spinal: C1 to C5 anterior gray horn

55. Functional component
FN COMP. NUCLEUS target origin
SE/SVE
(Somatomotor/
Branchiomotor)
Spinal nucleus of
Ascessory Nerve
(C1-C5)
Sternocleidomastoid &
Trapezius
-
SVE
(BRANCHIOMOTOR)
nucleus ambiguus Muscles of Pharynx & larynx -
GVE
(VISCEROMOTOR)
Dorsal nucleus of
vagus
Heart -

58. Course
• Cranial part:
• Rootlets arise from posterolateral sulcus of medula below the rootlets of vagus.
• In the jugular foramen combine with spinal part to form nerve trunk.
• At exit from jugular foramen leaves spinal root to combine with inferior ganglion
of vagus.
• Distributed through following branches of vagus:
• pharyngeal branch
• recurrent laryngeal
• cardiac branch

60. • Spinal part:
• Rootlets arise between anterolateral and posterolateral sulcus of C1 -C5 spinal
segments
• unite to form a single ascending spinal root of ascending nerve
• enters cranial cavity through foramen magnum.
• goes to intermediate compartment of jugular foramen
• joins the cranial root to form Acessory nerve trunk.
• At the exit of foramen, spinal part separates passes downward deep to styloid
process.
• pierces deep surface of sternocleidomastoid
• runs in posterior triangle and supplies trapezius.

64. Branches
• Communicating branches
• with C2, deep to sternocleidomastoid
• with C2 & C3 in posterior triangle
• with C3 & C4 deep to trapezius
• Distributing branches:
• To sternocleidomastoid
• To Trapezius

65. Applied
• Acessory nerve irritation causes spasm of SCM and
trapezius leading to spasmodic Torticollis.

66. Thank you