Gross Anatomy:
Review of Autonomics in the
Head and Neck
General principles of autonomic innervation
to the structures of the head and neck:
Cranial Nerves with Parasympathetic
Functional Componenents
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Olfactory
Optic
Oculomotor
Trochlear
Trigeminal
Abducens
Facial
Vestibulocochlear
Glossopharyngeal
Vagus
Accessory
Hypoglossal
CN I
CN II
CN III
CN IV
CN V
CN VI
CN VII
CN VIII
CN IX
CN X
CN XI
CN XII
(SVA)
(SSA)
(GSE, GVE-P)
(GSE)
(GSA, SVE)
(GSE)
(SVE, GSA, SVA, GVA, GVE-P)
(SSA, SSE)
(SVE, GSA, SVA, GVA, GVE-P)
(SVE, GSA, SVA, GVA, GVE-P)
(GSE)
(GSE)
Sensory
Sensory
Motor
Motor
Both
Motor
Both
Sensory
Both
Both
Motor
Motor
Head and Neck Parasympathetics – KEY Points
• CN V is the great sensory nerve to structures of the head and provides a
ready-made route to all structures which need to be innervated
autonomically
• The four parasympathetic ganglia [COPS] in the head are “associated”
with CN V:
– V1 (ciliary)
– V2 (pterygopalatine)
– V3 (submandibular and otic)
• Autonomic fibers of CN III, VII, and IX “hitchhike” along these routes to
gain their target organs
Head and Neck Sympathetics – KEY Points
• Preganglionic sympathetic axons arise from the IML cell column at T1 – T4
• Enter the sympathetic chain via white rami
• Ascend in the sympathetic chain
• All preganglionic fibers associate with viscera of the head and neck
synapse in the superior cervical sympathetic ganglion
• Therefore, THERE ARE NO PRE-GANGLIONIC SYMPATHETIC FIBERS IN THE
HEAD
Sympathetic
Pathways
C1 - C8
T1–- T4
L2
T1
L3 - Co
Postganglionics leave the
Superior Cervical Ganglion
as the:
 External carotid nerve: located on the surface
of the external carotid artery; distributes to
superficial viscera of the head/neck via
branches of this vessel
 Internal carotid nerve: located on the surface
of the internal carotid artery; forms a plexus
that contributes branches to the:
•Glands in the middle ear (caroticotympanic
branches)
•lacrimal gland and mucous glands of the
nasal cavity, oral cavity, pharynx [deep
petrosal nerve joins the nerve of the
pterygoid canal which in turn distribute via
branches of maxillary nerve].
•Dilator pupillae muscle [cavernous plexus
gives rise to the sympathetic root of the
ciliary ganglion that distribute by short
ciliary nerves].
Autonomic innervation of the ciliary and
pupillary muscles:
Parasympathetic
Innervation
The ciliary ganglion:
• has sensory, sympathetic and
motor roots
• receives preganglionic
parasympathetic axons (from
the brainstem/CN III) via the
motor root
• gives rise to postsynaptic
axons that travel in short
ciliary nerves to the ciliary
muscle and sphincter pupillae
Sympathetic Innervation
1.
postganglionic
sympathetic fibers arise
from the superior
cervical ganglion and
travel along the
cavernous plexus
2.
reach the orbit on
ophthalmic artery or CN
III
3.
traverse the ciliary
ganglion without
synapse
4.
Innervates the dilator
pupillae muscle and
superior tarsal muscle
Autonomic innervation of the mucous glands
of the head:
Parasympathetic Innervation
1.
preganglionic
parasympathetic
fibers course in CN
VII (greater petrosal
nerve  nerve of
the pterygoid canal)
2.
synapse in the
pterygopalatine
ganglion
3.
postganglionic
parasympathetic
fibers “hitchhike”
along branches of
CN V2 to reach the
lacrimal, oral,
palatal, nasal and
pharyngeal mucous
glands
Cranial Nerve VII
Sympathetic Innervation
1.
postganglionic sympathetic
fibers arise from the
superior cervical ganglion
and travel in the cavernous
plexus
2.
forms the deep petrosal
nerve and joins the greater
petrosal nerve to form the
nerve of the pterygoid
canal
3.
fibers traverse the
pterygopalatine ganglion
without synapse
4.
reach the viscera along
branches of the maxillary
artery and/or follow
branches of CN V
Pterygopalatine Ganglion
Autonomic innervation of the salivary glands:
Parasympathetic
Innervation
1. preganglionic
parasympathetic
fibers course in CN
VII (chorda tympani)
2. joins the lingual
nerve in the
infratemporal fossa
3. synapse in the
submandibular
ganglion
4. postganglionic
parasympathetic
fibers innervate
submandibular,
sublingual and
lingual salivary
glands
Parasympathetic
Innervation
• preganglionic
parasympathetic fibers
course in CN IX
(tympanic nerve
lesser petrosal
nerve)
• synapse in the otic
ganglion
• postganglionic
parasympathetic fibers
travel along CN V3
(auriculotemporal
nerve) to innervate the
parotid gland
Parasympathetic Routes to the Salivary Glands
Sympathetic Innervation
• postganglionic sympathetic
fibers arise from the
superior cervical ganglion
and travel in the external
carotid plexus
• travel on the facial artery
• reach the viscera along
branches CN V3
Autonomic innervation of the smooth muscle
and glands in the pharynx and larynx:
Parasympathetic
Innervation
• preganglionic parasympathetic fibers
course in CN X (pharyngeal branches,
internal laryngeal nerve, recurrent
laryngeal nerve)
• enter pharynx and larynx to synapse in
intramural ganglia
Sympathetic
Innervation
C1 - C8
• preganglionic sympathetic
fibers arise in the IML cell
column (T1 – 4)
• synapse in the
sympathetic chain
T1
T1 –- L2
T4
L3 - Co
• laryngopharyngeal
branches
A 24-year-old female presents to the emergency room 5-days after
a bar fight with the chief complaints of a “messed up hand and
funny eye”. Physical examination reveals the images below.
1. Where is the injury?
2. What is the diagnosis?
3. What other signs would most likely be present on PE?
A 54-year-old male presents to the emergency room with the
chief complaints of headache and hoarseness. Physical
examination reveals a weak gag reflex and the image below.
1. Where is the injury?
2. What is the diagnosis?
Horner’s Syndrome also occurs in:
• cervical spinal cord injury
• Brainstem strokes
• apical lung tumors