sympathetic innervation: superior, middle, inferior ganglion

Question 1

what is the sympathetic nervous system a division of?

Answer 1

the autonomic nervous system

Question 2

mechanism of sympathetic NS?

Answer 2

involuntary

Question 3

action of SNS?

Answer 3

acts with the parasympathetic system to maintain body homeostasis
‘fight or flight’ response

Question 4

where do the sympathetic fibres begin?

Answer 4

in the spinal cord

Question 5

Where do the sympathetic nerve fibres originate from?

Answer 5

from the thoracic region (T1-6)

Question 6

how do the sympathetic nerve fibres reach structures in the H+N?

Answer 6

ascend from T1-6

Question 7

After leaving the spinal cord, what do the fibres enter?

Answer 7

the sympathetic chain

Question 8

where does the sympathetic chain span?

Answer 8

spans from the base of the skull to the coccyx

Question 9

what is the sympathetic chain formed by?

Answer 9

formed by nerve fibres and ganglia (collections of nerve cell bodies)

Question 10

how many ganglion are there within the sympathetic chain? what are they?

Answer 10

There are three ganglia within this chain that are of interest – the superior, middle and inferior cervical ganglia

Question 11

what do the sympathetic fibres synapse with?

Answer 11

with ganglia (nerve cell bodies making up the sympathetic chain)

Question 12

where do post ganglionic branches continue into?

Answer 12

the head and neck

Question 13

what are each of the 3 ganglia related to?

Answer 13

specific arteries in the head and neck.

Question 14

how do the post-ganglionic fibres reach target organs?

Answer 14

The post-ganglionic fibres hitch-hike along arteries (and their branches - related to the ganglia) in order to reach their target organs

Question 15

what is the cervicothoracic ganglion?

Answer 15

In some individuals, the middle cervical ganglion is often absent and the inferior cervical ganglion is often fused with the first thoracic ganglion

Question 16

which 2 ganglion are commonly connected together?

Answer 16

the superior and middle cervical ganglia

Question 17

where is the superior cervical ganglion?

Answer 17

located posteriorly to the carotid artery, and anterior to the C1-4 vertebrae

Question 18

which important post ganglionic nerves arise from the superior cervical ganglion?

Answer 18

Internal carotid nerve
External carotid nerve
Nerve to pharyngeal plexus
Superior cardiac branch
Nerves to cranial nerves II, III IV, VI and IX
Gray rami communicantes

Question 19

where does internal carotid nerve (post-ganglionic nerve from superior cervical ganglion) travel? forming?

Answer 19

hitch-hikes along the internal carotid artery, forming a network of nerves

Question 20

what do branches from the internal carotid plexus innervate?

Answer 20

structures in the eye, the pterygopalatine artery and the internal carotid artery itself

Question 21

where does external carotid nerve (post-ganglionic nerve from superior cervical ganglion) travel? forming?

Answer 21

hitch-hikes along the common and external carotid arteries, forming a network of nerves

Question 22

what does external carotid nerve innervate?

Answer 22

smooth muscle of the arteries

Question 23

what does Nerve to pharyngeal plexus combine with? forming?

Answer 23

combines with branches from the vagus and glossopharyngeal nerves to form the pharyngeal plexus

Question 24

what does superior cardiac branch contribute to?

Answer 24

contributes to the cardiac plexus in the thorax

Question 25

where do Gray rami communicantes distribute sympathetic fibres to?

Answer 25

distributes sympathetic fibres to the anterior rami of C1-C4

Question 26

where is the middle cervical ganglion located?

Answer 26

anteriorly to the inferior thyroid artery and the C6 vertebra

Question 27

post-ganglionic fibres of the middle cervical ganglion?

Answer 27

grey rami communicantes thyroid branches middle cardiac branch

Question 28

where do grey rami comminucantes distribute its sympathetic fibres to? (branch of middle cervical ganglion)

Answer 28

to the anterior rami of C5 and C6

Question 29

where do thyroid branches travel along? (branch of middle cervical ganglion)

Answer 29

travel along the inferior thyroid artery

Question 30

where does thyroid branches distribute their fibres?

Answer 30

larynx, trachea, pharynx and upper oesophagus

Question 31

what does middle cardiac branch contribute to? (branch of middle cervical ganglion)

Answer 31

contributes to the cardiac plexus in the thorax

Question 32

where is the inferior cervical ganglion is situated?

Answer 32

anteriorly to the C7 vertebra

Question 33

what does inferior cervical ganglion occasionally fuse with? forming?

Answer 33

the first thoracic vertebrae, forming the cervicothoracic ganglion

Question 34

how many post-ganglionic fibres arise from inferior cervical ganglion? what are they?

Answer 34

3 branches: Gray rami communicantes Branches to the subclavian and vertebral arteries Inferior cardiac nerve

Question 35

where does gray rami communicantes distribute its sympatehtic fibres to? (branch of inferior cervical ganglion)

Answer 35

to the anterior rami of C7, C8 and T1

Question 36

what do Branches to the subclavian and vertebral arteries innervate? (branch of inferior cervical ganglion)

Answer 36

the smooth muscle present in the arteries

Question 37

what does inferior cardiac nerve contribute to? (branch of inferior cervical ganglion)

Answer 37

contributes to the cardiac plexus in the thorax