Download 1. Sympathetic fibers in the greater thoracic splanchnic nerve arise

1. Sympathetic fibers in the greater thoracic splanchnic nerve arise
from neuron cell bodies found in the:
brainstem
celiac ganglion
chain ganglion
spinal cord
superior mesenteric ganglion
2. Which nerve fiber would have its cell body in the lateral horn of the
spinal cord at segmental level T1?
Afferent fiber from cutaneous blood vessels of the nose
Afferent fiber from skin around the nipple
Efferent fibers to sweat glands in the lumbar region
Efferent fibers to skin of the forehead
Parasympathetic fibers to the heart
3. Gray rami communicantes contain postganglionic sympathetic
fibers that innervate which of the following structures in the
thoracic region?
aorta
heart
lung
sweat glands
trachea
4. In the midregion of the thorax the thoracic duct lies immediately
posterior to the:
aorta
azygos vein
esophagus
superior vena cava
trachea
5. Lymph nodes can be found in which mediastinal compartment(s)?
Anterior
Middle
Posterior
All of the above
None of the above
6. Which structure contains postganglionic sympathetic fibers?
greater thoracic splanchnic nerve
recurrent larygneal nerve
white ramus communicans
ulnar nerve
vagus nerve
7. Which posterior mediastinal structure is most closely applied to the
posterior surface of the pericardial sac?
aorta
azygos vein
esophagus
thoracic duct
trachea
8. A tumor of the posterior mediastinum is most likely to compress
which of the following structures?
Arch of the aorta
Esophagus
Inferior vena cava
Pulmonary trunk
Trachea
9. The aorta is located in which mediastinal compartment(s)?
Anterior only
Anterior and middle
Middle only
Middle and posterior
Posterior only
10.
While performing transesophageal echocardiography on a
patient, the posterior wall of the esophagus, immediately behind
the left atrium, was punctured from within. The patient
subsequently developed an infection in the space around the
esophagus at this point, namely the:
Anterior mediastinum
Middle mediastinum
Posterior mediastinum
Superior mediastinum
11.
Since the puncture in the previous question was through the
posterior wall of the esophagus, the doctors were also very
concerned about possible damage to a thin-walled vessel just
behind the esophagus and between the azygos vein and aorta,
i.e., the:
Hemiazygos vein
Left bronchial vein
Left pulmonary vein
Superior vena cava
Thoracic duct
12.
During a surgical procedure, a patient's right sympathetic
trunk was accidentally severed just cranial to the level of spinal
nerve T1. Which function would be left intact in the affected
region?
Arrector pili muscle activity
Dilation/constriction of blood vessels
Sweat production
Visceral reflex activity
Voluntary muscle activity
13.
Most of the drainage of the thoracic body wall reaches the
superior vena cava via the azygos vein. A notable exception is the
left superior intercostal vein, which normally drains into the:
Left brachiocephalic vein
Left bronchial vein
Left pulmonary vein
Left subclavian vein
Superior vena cava
14.
You are observing a physician perform a thoracoscopic
procedure. She pushes the deflated lung anteroinferiorly and
points out a nervous structure lying across the heads of the ribs.
You identify this structure as the
Greater thoracic splanchnic nerve
Sympathetic trunk
Phrenic nerve
Pulmonary plexus
Vagus nerve
15.
An enlarging lymph node gradually constricts the flow of
blood in the azygos venous arch. Which vessel would enlarge as a
result of collateral drainage?
Superior vena cava
Inferior vena cava
Internal thoracic vein
Right brachiocephalic vein
Superior epigastric vein
16.
During a procedure to harvest lymph nodes in the posterior
mediastinum, the thoracic duct is accidentally cut. The resulting
accumulation of lymph in the pleural cavity is referred to as:
Pleurisy
Chylothorax
Pyothorax
Hemothorax
Lymphedema
17.
A cancerous growth from the body of the 9th thoracic
vertebra exerts pressure anterolaterally. Which structure lies in
direct contact with this growth?
Right vagus nerve
Right phrenic nerve
Right sympathetic trunk
Right greater thoracic splanchnic nerve
Right 9th intercostal nerve
18.
A 45-year-old female patient complains of excessive
sweating on the right side of the face and neck and in the right
armpit region, where it leaves her clothing constantly stained with
moisture. It is now such a terrible social embarrassment that she
has become withdrawn and self-conscious. Since no medical
treatment has proven effective, she is considering surgical
denervation of the sweat glands in the affected areas. Which
structure(s) might be removed or cut in order to alleviate her
condition?
Cervicothoracic (stellate) ganglion
Dorsal roots of cervical nerves
Greater thoracic splanchnic nerve
Lumbar sympathetic trunk
Vagus nerve
19.
While viewing an exploratory surgery on a patient injured in
an automobile accident, you see the surgeon elevate the
esophagus off the vertebral bodies and look in the area between
the azygos vein and descending aorta. What structure was she
most likely looking for?
Greater thoracic splanchnic nerve
Left recurrent laryngeal nerve
Right pulmonary artery
Sympathetic trunk
Thoracic duct
20.
The ductus arteriosus sometimes remains open after birth,
requiring surgical closure. When placing a clamp on the ductus,
care must be taken to avoid injury to what important structure
immediately dorsal to it?
Accessory hemiazygos vein
Left internal thoracic artery
Left phrenic nerve
Left recurrent laryngeal nerve
Thoracic duct
21.
A frail, elderly man, suspected of having widespread cancer
of the lungs and bronchi, is brought in for bronchoscopic
examination. The instrument is inserted into the airway, where it
accidentally punctures the thin, brittle posterior wall of the
diseased right main bronchus. A sudden gush of blood
immediately indicates that the instrument has also torn the wall of
the blood vessel immediately behind the right main bronchus, i.e.,
the:
Azygos vein
Left brachiocephalic artery
Pericardiacophrenic artery
Right pulmonary vein
Superior vena cava
1. The correct answer is:
spinal cord
The sympathetic fibers in the greater thoracic splanchnic nerve are
preganglionic sympathetic fibers that have left the sympathetic chain and
are going to synapse in an abdominal ganglia. These preganglionic
sympathetic fibers originate in the lateral horn of the spinal cord grey
matter. The celiac ganglia and the superior mesenteric ganglia are the
two ganglia where the fibers from the greater thoracic splanchnic nerve
can go to synapse. Finally, remember that these fibers did not originate
in the chain ganglia--the fibers from there are the postganglionic
sympathetic fibers.
2. The correct answer is:
efferent fibers to the skin of the forehead
Efferent fibers to the skin of the forehead might have their cell bodies
located in the lateral horn of the T1 level. Because these fibers are at the
superior edge of the thoracolumbar outflow (located from T1 to L2), they
might go up the chain, synapse at a higher ganglion, and provide
sympathetic innervation to the head and face. Afferent fibers would not
have their cell bodies located in the lateral horn--afferent sensory fibers
have cell bodies in dorsal root ganglia. Efferent fibers to the sweat
glands of the lumbar region would be sympathetic fibers, but these cell
bodies would be located at the T12, L1, or L2 levels--not at T1. T1 is too
high for the lumbar region! Finally, parasympathetic fibers to the heart
come from the vagus nerve.
3. The correct answer is:
sweat glands
Sympathetic fibers innervate sweat glands by synapsing in the
sympathetic chain, jumping on the grey rami to rejoin the spinal nerve,
and heading for the periphery. The sympathetic nerves to the heart,
aorta, lungs, and bronchi are carried in the cardiac and pulmonary
plexuses. These fibers are not found in spinal nerves.
4. The correct answer is:
esophagus
In the mid thorax, the aorta, thoracic duct, and azygos vein are all
posterior to the esophagus. (They are in that order, from left to right.)
The superior vena cava and the trachea are not located in the mid
thorax--the superior vena cava terminates as it feeds into the right atrium
and the trachea ends as it splits into the two mainstem bronchi which
enter the lungs.
5.
The correct answer is:
all of the above
Lymph nodes are found in all of the mediastinal compartments. They are
the one structure that can be found in the anterior, middle, and posterior
compartments. What else is in each compartment? The anterior
compartment contains areolar tissue and sternopericardial ligaments.
The middle compartment contains the pericardium,heart, great vessels,
and bronchi. The posterior compartment contains the descending
thoracic aorta, azygos system, esophagus, and thoracic duct.
6. The correct answer is:
ulnar nerve
White rami communicantes carry presynaptic sympathetic fibers to the
sympathetic trunk. When a presynaptic nerve fiber reaches the
sympathetic chain, there are three things that can happen. First, the
nerve fibers can enter a ganglia, synapse at that level, and rejoin the
spinal nerve via the grey rami communicantes. Second, the
preganglionic nerve fibers can travel up and down the trunk, synapse in
a ganglia at another level, and then rejoin a spinal nerve. This is how
sympathetic fibers join spinal nerves at the cervical and lumbar levels,
which are above and below the lateral horn. Third, some preganglionic
fibers do not synapse in the trunk and, instead, form splanchnic nerves.
These nerves descend into the abdomen and synapse in other ganglia.
The greater thoracic splanchnic nerve contains preganglionic fibers that
are destined to synapse in the celiac plexus. The recurrent laryngeal
nerve provides motor and sensory innervation to the upper esophagus
and pharynx. Finally, the vagus nerve is a mixed nerve that carries
preganglionic parasympathetic fibers. None of these nerves carry
postganglionic sympathetic fibers.
The ulnar nerve innervates muscles of the hand and forearm, and
provides some sensory innervation to skin of the hand. The ulnar nerve
is derived from ventral primary rami, all of which carry postganglionic
sympathetic fibers (to innervate vascular smooth muscle, arrector pili
muscles, and sweat glands).
7. The correct answer is:
esophagus
The esophagus is closely related to the posterior surface of the
pericardial sac. After coming from the heart, the aorta arches over the
left pulmonary artery and left bronchus. Eventually, this vessel is
posterior to the esophagus. The azygos vein, on the right side of the
thorax, arches over the right pulmonary artery and bronchus. It is also
posterior to the esophagus. The thoracic duct is posterior to the
esophagus as well and does not contact the pericardial sac. Finally, the
trachea is superior to the heart.
8.
The correct answer is:
esophagus
The posterior mediastinum is bounded superiorly by the plane through
the sternal angle and T4/5, inferiorly by the diaphragm, anteriorly by the
middle mediastinum, and posteriorly by the spinal cord. This area
contains the descending thoracic aorta, the azygos system, the
esophagus, the thoracic duct, and lymph nodes. Of the answer choices,
the esophagus is the only one in the posterior mediastinum. The great
vessels and bronchi at the roots of the lung are in the middle
mediastinum.
9. The correct answer is:
middle and posterior
The ascending aorta is located in the middle mediastinum, along with
the other great vessels. The aortic arch is located in the lowest part of
the superior mediastinum (its lower border lies at the level of the sternal
angle). The descending aorta is in the posterior mediastinum.
Remember what's in what part of the mediastinum--it's important!
10.
The correct answer is:
posterior mediastinum
The esophagus is in the posterior mediastinum, along with the
descending aorta, thoracic duct, and azygos system.
11. The correct answer is:
thoracic duct
The thoracic duct is found directly behind the esophagus in the posterior
mediastinum, with the aorta to its left and the azygos vein to its right.
This relationship between these three vessels is an important one to
keep in mind! The other vessels do not share the same relationship with
the azygos and aorta.
12. The correct answer is:
voluntary muscle activity
The sympathetic nervous system is not responsible for voluntary muscle
activity. The neurons which supply voluntary muscles originate from the
ventral horn of the spinal cord. One of the main functions of sympathetic
nerves is maintaining the tone of blood vessels--if these nerves were
damaged, it would be difficult to regulate vascular tone. The sympathetic
nervous system also regulates the arrector pili muscles, sweat
production, and visceral reflexes.
13. The correct answer is:
Left brachiocephalic vein
The left superior intercostal vein drains intercostal spaces 2-4, and then
drains into the left brachiocephalic vein. See Netter Plate 231 for a
picture of this relationship. The left bronchial vein is a small vein that
removes venous blood from the lungs--it drains into the accessory
hemiazygos vein. The left pulmonary veins carry oxygenated blood from
the lung to the left atrium of the heart. The left subclavian vein is a
continuation of the left brachiocephalic vein--this vein drains blood from
the arm into the left brachiocephalic vein. The superior vena cava is
formed by the junction of the left and right brachiocephalic veins; it
delivers blood to the right atrium.
14. The correct answer is:
Sympathetic trunk
The sympathetic trunk can be found on the posterior wall of the thorax,
lying on the heads of the ribs. It contains the cell bodies of
postganglionic sympathetic fibers. When a nerve fiber reaches the
sympathetic chain, there are three things that can happen. First, the
nerve fibers can enter a ganglia in the trunk, synapse at that level, and
rejoin the spinal nerve via the grey rami communicantes. Second, the
preganglionic nerve fibers can travel up and down the trunk, synapse in
a ganglia at another level, and then rejoin a spinal nerve. This is how
sympathetic fibers join spinal nerves at the cervical and lumbar levels,
which are above and below the lateral horn. Third, some preganglionic
fibers do not synapse in the trunk and, instead, form splanchnic nerves.
These nerves descend into the abdomen and synapse in other ganglia.
You really need to understand all three of these possibilities!
The greater thoracic splanchnic nerve is one of the splanchnic nerves
that is carrying preganglionic fibers away from the trunk. It lies medial to
the trunk, on the vertebral bodies, and carries fibers to the celiac plexus.
The phrenic nerve travels through the anterior thorax to innervate the
diaphragm--it's not found near the heads of the ribs. The pulmonary
plexus is located along the pulmonary vessels and primary bronchi in the
root of the lung--it carries both sympathetic and parasympathetic fibers
to the lungs. The vagus nerve is the major nerve carrying
parasympathetic fibers in the thorax and to the abdomen. It begins in the
anterior portion of the thorax, then enters the posterior mediastinum and
forms the esophageal plexus covering the esophagus.
15. The correct answer is:
Internal thoracic vein
The internal thoracic vein would provide a collateral route for drainage if
the azygos vein was obstructed. In the case of an obstruction, blood
could flow from the posterior intercostal veins (which usually drain into
the azygos) into the anterior intercostal veins, enter the internal thoracic
vein, and drain into the right brachiocephalic vein. This would allow the
blood to bypass the blockage. The right brachiocephalic vein would be
receiving more blood due to this blockage, but it wouldn't be the vessel
that would enlarge--the internal thoracic vein would become distended.
The superior epigastric vein is an inferior extension of the internal
thoracic vein--it is too inferior to assist with collateral circulation.
16. The correct answer is:
Chylothorax
A chylothorax is a pleural effusion composed of lymphatic fluid due to
disruption of the thoracic duct. Pleurisy refers to the inflammation of the
pleura with exudation into the pleural cavity. A pyothorax is an infection
that occurs in the pleural space, where pus accumulates within the
pleural cavity. A hemothorax involves the accumulation of blood in the
pleural space. Finally, lymphedema is a swelling in a body part cause by
the obstruction of lymphatic flow or the removal of the lymphatic vessels
in a region.
17. The correct answer is:
Right greater thoracic splanchnic nerve
The thoracic splanchnic nerves lie on the anterior surfaces of the
vertebral bodies. Remember, the splanchnic nerves lie medial to the
sympathetic trunk, which is lying on the heads of the ribs. The vagus
nerve lies in the anterior chest and eventually forms the esophageal
plexus, covering the esophagus. The phrenic nerve innervates the
diaphragm--it is not near the posterior wall of the thorax. Intercostal
nerves run in the intercostal groove at the posterior border of the rib-they are not near the vertebral bodies.
18. The correct answer is:
Cervicothoracic (Stellate) gangion
The cervicothoracic ganglion is a sympathetic ganglion, formed by the
fusion of the inferior cervical sympathetic ganglion and the T1 ganglion
of the sympathetic trunk. The postsynaptic sympathetic fibers from this
ganglia innervate the vascular smooth muscle and sweat glands of the
C8 & T1 cutaneous distribution on chest & upper limb. Since the sweat
glands in the right armpit are innervated by fibers coming from the
stellate ganglion, this ganglion might need to be removed or cut to
alleviate the patient's condition.
The dorsal roots of cervical spinal nerve carry afferent, sensory fibers.
These sensory fibers are not involved in innervation to glands. The
greater thoracic splanchnic nerve carries preganglionic sympathetic
fibers to the abdomen, where they synapse in the celiac ganglion. The
lumbar sympathetic trunk is involved with sympathetic innervation in the
abdomen--it is far from the area where this patient is experiencing
problems. Finally, the vagus nerve carries parasympathetic fibers to the
thorax and abdomen; it does not innervate sweat glands.
19. The correct answer is:
thoracic duct
The thoracic duct lies in the posterior mediastinum between the aorta on
its left and the azygos vein on its right. These three structures are all
found posterior to the esophagus. The greater thoracic splanchnic nerve
lies anterior to the vertebral bodies, behind the azygos, thoracic duct,
and aorta. The left recurrent laryngeal nerve is found in the middle
mediastinum, looping under the aortic arch before it ascends to the
larynx. The right pulmonary artery is also in the middle mediastinum--it
leaves the heart and enters the root of the right lung. The sympathetic
trunk lies on the heads of the ribs on the posterior wall of the thorax.
20. The correct answer is:
Left recurrent laryngeal nerve
The left recurrent laryngeal nerve is closely associated with the aortic
arch and the ligamentum arteriosum/ductus arteriosus. As the left vagus
nerve passes near the aortic arch, it gives offf the left recurrent laryngeal
nerve. This nerve then loops under the aortic arch, lateral to the
ligamentum arteriosum, and ascends to the larynx in the
tracheoesophageal groove. During surgery to close a patent ductus
arteriosus, a surgeon must be careful to protect the left recurrent
laryngeal nerve, which is lateral to the duct that is being ligated.
The accessory hemiazygos vein is a vein on the left side of the body
which drains blood from the left chest wall into the azygos vein. The
internal thoracic artery is a branch of the subclavian artery which
supplies blood to the anterior chest wall and gives rise to the anterior
intercostal arteries. The left phrenic nerve passes through the thorax to
innervate the diaphragm. It is a bit lateral to the area where the surgeon
is clamping the ductus arteriosus, so it would not be at risk during the
procedure. Finally, the thoracic duct is found deep in the posterior
mediastinum, lying between the aorta and azygos veins.
21. The correct answer is:
Azygos vein
The azygos vein lies immediately behind the right mainstem bronchus.
This vein then arches over the right mainstem bronchus to drain blood
into the superior vena cava. So, this must be the structure that was
damaged during the bronchoscopy.The left brachiocephalic artery
doesn't exist, but the brachiocephalic trunk is a branch off the aortic arch
which travels far superior to the area of interest. The pericardiacophrenic
artery is a branch of the internal thoracic artery which accompanies the
phrenic nerve. It is anterior to the right bronchus. The right pulmonary
veins are inferior and anterior to the right mainstem bronchus. Finally,
the superior vena cava is superior and anterior to the right mainstem
bronchus. Take a look at Netter Plate 230 for a better understanding of
these relationships.