L27, 28 - Nerves of head and neck Flashcards
List all the parasympathetic ganglia of Head and neck?
Ciliary
Pterygopalatine
Submandibular
Otic
List all the special sensory ganglia of head and neck?
Vestibular
Spiral
Geniculate
Inferior vagal (nodose ganglion)
Inferior glossopharyngeal* mixed general and special sensory)
List all the general sensory ganglia of the head and neck?
Neck: T2-T5 Dorsal root ganglia
Head:
Superior vagal (Jugular ganglion)
Superior glossopharyngeal
Trigeminal
Inferior glossopharyngeal* mixed general and special sensory
List all the sympathetic ganglia of Head and neck?
Superior, Middle, Inferior cervical sympathetic ganglia
Describe the tract of somatic motor neuron from spinal cord.
Anterior horn of spinal cord >> ventral root >> Spinal nerve
>> exit via dorsal and ventral ramus to skeletal muscles of body
Describe the tract of visceral* motor neuron from spinal cord.
Lateral horn of spinal cord
>> ventral root >> spinal nerve >> White ramus to sympathetic ganglion/ paravertebral ganglion: 3 exits:
1) PreGN fiber >> white rami communicantes >> synapse at sympathetic ganglia of another vertebral level >> PostGN fiber exit via grey rami communicantes >> spinal nerve
2) PreGN >> white rami communicantes >> synapse at sympathetic ganglion of same level >> grey rami communicantes to spinal nerve >> exit via sympathetic nerve
3) PreGN synapse at ganglion >> PostGN exit via sympathetic splanchnic nerve to prevertebral ganglia
List the anterior and posterior branches of the cervical plexus?
C2-C5 spinal nerves form cervical plexus
Posterior branches
C2 = Greater + Lesser occipital n.
C3 = Third occipital n.
Anterior branches
- Superior and Inferior roots of Ansa Cervicalis
- Great Auricular nerve (C2,C3)
- Transverse Cervical nerve (C2,C3)
- Supraclavicular nerve (C3,C4)
- Phrenic nerve
Describe the cutaneous distribution of spinal nerves at the head and neck**?
Dorsal ramus of spinal nerve C2-C5 supply skin behind vertex:
Great occipital (C2),
Lesser occipital (C2),
Third occipital (C3),
Branch from C4, Branch from C5
Ventral ramus of spinal nerves C2-C5 mix in plexus: cutaneous regions anterior to vertex supplied by mixed spinal nerves:
Great auricular (C2, C3),
Transverse cervical (C2, C3),
Supraclavicular (C3,C4) with Medial, Intermediate, Lateral branches
List the cranial nerves with only sensory function
⎼ Olfactory (I)
⎼ Optic (II)
⎼ Vestibulocochlear (VIII)
List the cranial nerves with only motor function?
⎼ Oculomotor (III)
⎼ Trochlear (IV)
⎼ Abducent (VI)
⎼ Accessory (XI)
⎼ Hypoglossal (XII)
List the cranial nerves with mixed motor and sensory functions?
⎼ Trigeminal (V)
⎼ Facial (VII)
⎼ Glossopharyngeal (IX)
⎼ Vagus (X)
List all the effectors of the sympathetic system in head and neck?
Smooth muscles:
Dilator pupillae
Superior tarsal muscle
Erector pili muscle
Blood vessel wall muscles
Sweat glands
Define the arteries associated with the superior, middle and inferior cervical ganglia?
Superior (C1-C4) = Common, external and internal carotid arteries
Middle (C5,C6)= Inferior thyroid artery
Inferior (C7,C8) = Vertebral and subclavian arteries
Describe how sympathetic chain from T1-L2 can reach structures in the head and neck?
T1- L2 Intermediolateral (IML) cell columns at the Lateral horn of spinal cord
>> ventral root >> spinal nerve >> white ramus communicantes
>> PreGN fiber travel up to superior cervical ganglia and synapse
>> gray ramus communicantes >> PostGN fiber reach organs/ effectors in head
Describe the distribution of nerves from the superior cervical ganglion to various plexues? (3)
From Superior cervical ganglion: Post-GN fibers:
1) Internal carotid nerve plexus >> Tarsal muscle, pupillary dilator, ciliary body, cerebral vessels, Lacrimal gland
2) External carotid nerve plexus >> nasal gland, salivary glands
3) Gray rami communicantes >> skin vessels, sweat glands, arrectores pili muscle
