Organization of the Thoracic Viscera I & II

Question 1

thoracic skeleton:

___ & ___ form an ___

all ribs slope ___ from their vertebral attachment

Answer 1

rib cage, thoracic vertebral column, irregularly shaped cone

downward

Question 2

superior thoracic aperture (thoracic outlet):

definition

3 boundaries

Answer 2

passageway for trachea, esophagus, many vessels & nerves

(1) first thoracic vertebra
(2) first pair of ribs & costal cartilages
(3) superior margin of manubrium sterni

Question 3

inferior thoracic aperture:

boundaries (3)

closed by the ___ separating the ___

Answer 3

(1) 12th thoracic vertebrae
(2) costal margin
(3) xiphosternal joint

diaphragm, thoracic & abdominal viscera

Question 4

thoracic cavity:

consists of ___

bounded by___

suprapleural membrane

Answer 4

two pleural cavities enclosing the lungs & the mediastinum

the thoracic wall, the diaphragm, & the suprapleural membrane

thickening of endothoracic fascia above the superior thoracic aperture which limits bulging of the lungs into the neck

Question 5

pleurae:

___ membranes that cover the ___

line the ___

composed of ___ that produces ___

connective tissue is strong enough to support ___

Answer 5

thin serous, surface of the lungs

walls, roof, & floor of the pleural cavities

mesothelium (simple squamous epithelium), serous fluid & connective tissue

blood vessels, nerves, & lymphatic vessels

Question 6

visceral pleura

Answer 6

covers the lungs

Question 7

parietal pleura

Answer 7

lines the walls, roof, & floor of the pleural cavities

Question 8

parietal & visceral pleura are ___ with each other around the ___ (___)

Answer 8

continuous

root of the lung (structures entering & leaving the lung & attaching the lungs to the mediastinum)

Question 9

divisions of parietal pleura:

costal pleura

cervical pleura (cupola)

diaphragmatic pleura

mediastinal pleura

Answer 9

lines thoracic wall

extends through thoracic inlet into neck

covers diaphragm

covers the mediastinal surface of each pleural sac

Question 10

pulmonary ligament:

___ pleura is reflected at the ___ to become continuous w/ the ___

at this point, it ___

___ layer of ___

Answer 10

mediastinal parietal pleura, the root of the lung, visceral pleura covering the lung

sags below the hilus as a shirt cuff might hang below a person’s wrist forming a potential space

double, pleura

Question 11

lines of pleural reflection

Answer 11

sharp lines of reflection where costal pleura become continuous w/ the mediastinal & diaphragmatic pleura & limit the pleural cavities

Question 12

pleural sacs:

far apart in the ___

converge as they’re traced ___ toward the ___ where they contact each other

Answer 12

region of the cupola

downward, sternal angle

Question 13

right pleura:

continuous ___

swings ___

Answer 13

straight downward close to the midline

outward & downward along the 7th costal cartilage

Question 14

left pleura:

anterior reflection deviates ___ at about the level of the ___

it’s usually lateral to the ___ at the level of the ___

it swings ___ along the ___

deviation of left pleura: ___

Answer 14

laterally, 4th rib

sternum, 5th & 6th intercostal spaces

outward & downward, 7th costal cartilage

cardiac notch

Question 15

lower borders of pleural reflections (right & left):

crosses 8th rib at the ___

crosses 10th rib at the ___

crosses 12th rib ___

Answer 15

mid-clavicular line

mid-axillary line

adjacent to vertebral border

Question 16

comparable surface markings for the lungs:

crosses 6th rib at the ___

crosses 8th rib at the ___

crosses 10th rib ___

Answer 16

mid-clavicular line

mix-axillary line

adjacent to vertebral border

Question 17

pleural recesses:

in life, lungs don’t ___

therefore, the surface markings of the lungs & the ___ pleura ___

here, portions of the ___ pleura are in contact w/ ___

Answer 17

extend to limits of pleural cavities even during maximum inspiration

parietal, don’t coincide

parietal, each other

Question 18

major recesses

Answer 18

costodiaphragmatic recesses - at the sharp reflection of the costal pleura onto the diaphragmatic pleura

costomediastinal recesses - at the sharp anterior reflections of the costal pleura onto the mediastinal pleura

Question 19

left costomediastinal recess

___ than the right recess due to the ___

the ___ enters this recess during ___

Answer 19

larger, cardiac notch of the left lung

lingula of the left lung, deep inspiration

Question 20

mediastinum:

___ b/n the ___

divided into ___ by ___ which passes through the ___ & the ___

Answer 20

mobile midline septum, pleurae & lungs

superior & inferior mediastinum, an imaginary plane, sternal angle, lower border of the 4th thoracic vertebra

Question 21

superior mediastinum:

lies ___

limited superiorly by the ___

situated chiefly behind the ___

posterior boundary is the ___

Answer 21

above the imaginary plane

superior thoracic aperture

manubrium sterni

first four thoracic vertebrae

Question 22

inferior mediastinum:

lies below the ___

limited inferiorly by the ___

further subidived into ___

Answer 22

imaginary plane (sternal angle)

diaphragm

anterior mediastinum, middle mediastinum, & posterior mediastinum

Question 23

middle mediastinum

Answer 23

composed of pericardial sac & its contents

Question 24

anterior mediastinum

Answer 24

area between pericardial sac & sternum

Question 25

posterior mediastinum:

area between ___

situated behind ___ extending from the ___

Answer 25

vertebral bodies & pericardial sac

pericardial sac, 5th through 12th thoracic vertebrae

Question 26

main contents of superior mediastinum (anterior to posterior) (10)

Answer 26

thymus gland
brachiocephalic veins & superior vena cava
aortic arch & 3 branches
vagus & phrenic nerves
cardiac plexus of nerves
left recurrent laryngeal nerve (not the right)*
trachea
esophagus
thoracic duct
lymph nodes

Question 27

main contents of posterior mediastinum (7)

Answer 27

esophagus
esophageal plexus
thoracic aorta
thoracic sympathetic trunks (2 total)
thoracic splanchnic nerves
thoracic duct
azygous system of veins

Question 28

thymus gland (superior mediastinum):

lies immediately behind the ___ & may extend into the ___ & the ___

after puberty, it’s largely replaced by ___

Answer 28

manubrium sterni, base of the neck, anterior mediastinum

fat

Question 29

trachea & esophagus (superior mediastinum):

fill ___ aperture in ___ plane b/n ___

trachea lies ___ esophagus & bifurcates ___

above root of lung, trachea & esophagus are crossed by ___ on the right & the ___ on the left

Answer 29

superior thoracic, median, apices of lungs

in front of, behind the sternal angle

azygous vein, arch of the aorta

Question 30

carina (superior mediastinum):

cartilaginous ridge within the ___ that runs antero-posteriorly b/n the ___ at the site of the ___ at the lower end of the ___

this ridge lies to the ___ of the midline

Answer 30

trachea, two primary bronchi, tracheal bifurcation, trachea

left

Question 31

arch of aorta (superior mediastinum):

commences at the right border of the ___, runs upward, backward, & to the left in front of the ___

passes downward to the left of the ___ & ___ & ends at the ___

contains the ___ & the ___ in its concavity

Answer 31

sternal angle, trachea

trachea, esophagus, sternal angle

right pulmonary artery, left principal bronchus

Question 32

aortic knuckle (superior mediastinum)

Answer 32

left curve of the arch of the aorta creates this of posterior-anterior chest x-rays

Question 33

usual branches of the arch of the aorta (superior mediastinum) (3)

all three are crossed anteriorly by the ___

Answer 33

brachiocephalic trunk

left common carotid artery

left subclavian artery

left brachiocephalic vein

Question 34

brachiocephalic trunk (superior mediastinum):

passes upward & to the right of the ___ & divides into the ___ & ___ behind the ___ joint

Answer 34

trachea, right subclavian, right common carotid arteries, right sternoclavicular

Question 35

left common carotid artery (superior mediastinum):

passes upward to the left of the ___ & enters the ___ behind the ___

Answer 35

trachea, neck, left sternoclavicular joint

Question 36

left subclavian artery (superior mediastinum):

arises behind the ___

Answer 36

left common carotid

Question 37

coarctation of the aorta:

aortic arch is abnormally ___ just beyond the ___ branch

for blood to reach that part of the aorta beyond the constriction, it must flow from branches arising ___ the constriction and follow ___ channels to reach branches arising ___ the constriction

the ___ arteries & the ___ channels become greatly ___ to accommodate the demands of the increased blood flow

a pulse can be found in the ___ spaces

the dilated ___ arteries press on the ___ border of the ribs causing localized areas of ___

these can be seen in x-ray films as ___ of the ___ border of the ribs

Answer 37

narrow/constricted, left subclavian

before, anastomotic, beyond

intercostal, anastomotic, dilated

intercostal

intercostal, inferior, resorption

notching, inferior

Question 38

brachiocephalic veins (superior mediastinum):

right & left brachiocephalic veins are formed by the union of the ___ & ___ behind the ___

the left brachiocephalic vein passes obliquely downward & to the right & unites w/ the ___ to form the ___ behind the ___

Answer 38

subclavian, internal jugular veins, right & left sternoclavicular joints

right brachiocephalic vein, superior vena cava, sternal end of the first costal cartilage

Question 39

superior vena cava (superior mediastinum):

descends & enters the ___ behind the ___

receives the ___ just before entering

Answer 39

right atrium of the heart, third right costal cartilage

azygous vein

Question 40

vagus nerves (superior mediastinum):

at the root of the neck, both right & left vagus nerves lie b/n the ___ & the ___

both descend in front of the ___

both descend in the ___ behind the ___

Answer 40

internal jugular vein, common carotid arteries

first part of the subclavian arteries

thorax, roots of the lungs

Question 41

recurrent laryngeal nerves (superior mediastinum):

arise from each of the ___ & ascend to supply the ___

Answer 41

vagus nerves, larynx

Question 42

left recurrent laryngeal nerve* (superior mediastinum):

hooks around the ___ behind the ___

ascends in a groove b/n the ___ & ___

Answer 42

left side of the arch of the aorta, ligamentum arteriosum

trachea, esophagus

Question 43

right recurrent laryngeal nerve* (superior mediastinum):

hooks around the ___ in the root of the ___

not found in the ___

Answer 43

right subclavian artery, neck

mediastinum

Question 44

phrenic nerves (superior mediastinum)

formed from the ___

both nerves enter the superior mediastinum b/n the ___ & ___ & lateral to the ___

both nerves descend ___ of the roots of the lungs*

Answer 44

ventral rami of C3, C4, & C5

subclavian artery, vein, vagus nerves

in front of

Question 45

innervation of phrenic nerves (superior mediastinum):

somatic efferent (___) (1)

somatic afferent (___, ___) (5)

Answer 45

(motor)
- diaphragm

(sensory, pain sensation):*

• fibrous pericardium
• parietal serous pericardium
• mediastinal parietal pleura
• central part of the diaphragmatic parietal pleura
• central part of the diaphragmatic parietal peritoneum

Question 46

esophagus (posterior mediastinum):

begins as a continuation of the ___ at the level of ___

enters the superior mediastinum b/n the ___ & the ___ & behind the ___

enters the posterior mediastinum to the right of the ___ & behind the ___ & ___

deviates to the left crossing in front of the ___ just before it passes through the diaphragm at the level of ___*

Answer 46

pharynx, C6

trachea, vertebral column, left principal bronchus

aorta, pericardium, left atrium

aorta, T10*

Question 47

esophageal constrictions (superior to inferior) (posterior mediastinum):

where the ___ joins the upper end

where it contacts the ___

where it contacts the ___

the ___ of the diaphragm

Answer 47

pharynx

arch of the aorta

left principal bronchus

esophageal hiatus

Question 48

esophageal plexus (posterior mediastinum):

as the vagus nerves reach the esophagus, each nerve ___ & there is an interchange of ___ b/n the nerves forming the esophageal plexus

a little above the diaphragm, the plexus usually gives rise to two ___

the one on the left turns forward & is referred to as the ___

the one on the right turns backward & is referred to as the ___

Answer 48

breaks up into several trunks, branches

two nerve trunks

anterior vagal trunk

posterior vagal trunk

Question 49

descending throacic aorta (posterior mediastinum):

begins as a continuation of the ___ at the left side of the ___

it descends downward at first on the left side of the ___ & then gradually approaches the ___

it passes through the ___ of the diaphragm at the level of ___

Answer 49

arch of the aorta, sternal angle

vertebral bodies, midline

aortic hiatus, T12

Question 50

thoracic branches (posterior mediastinum) (5)

Answer 50

lower nine posterior intercostal arteries
subcostal arteries
bronchial arteries
esophageal arteries
superior phrenic arteries

Question 51

azygous venous system (posterior mediastinum)

primary purpose is to ___

system receives blood from ___

provides an alternative root for ___

Answer 51

drain blood from the body wall

some of the thoracic viscera

venous return from the lower parts of the body should the main venous channel be obstructed

Question 52

azygous venous system (posterior mediastinum):

vessels on two sides of body are ___

longitudinal channel on right is called the ___

on the left, the channel usually consists of two veins: the ___ & the ___

considerable ___ in azygous system

Answer 52

vessels on two sides of body are assymmetric

longitudinal channel on right is called the azygous vein

hemiazygous, accessory hemiazygous

variation

Question 53

azygous venous system: major tributaries (posterior mediastinum) (5)

Answer 53

most of posterior intercostal veins
bronchial veins
esophageal veins
pericardial veins
mediastinal veins

Question 54

thoracic duct (posterior mediastinum):

begins in ___ as a dilated sac called the ___

ascends through ___ & passes upward on right side of ___ b/n ___ & ___

at about the level of ___, begins crossing toward the left & reaches the left border of the ___ at level of ___

runs upward into the root of the ___ & empties into the venous system at the junction of the ___ & ___

Answer 54

abdomen, cysterna chyli

aortic hiatus, aorta, aorta, azygous vein

T5, esophagus, sternal angle

neck, left subclavian, left internal jugular veins