Mediastinum/Pericardial Cavity Development Flashcards Preview

S&F III: Exam 1 > Mediastinum/Pericardial Cavity Development > Flashcards

Flashcards in Mediastinum/Pericardial Cavity Development Deck (58):
1

Superior Border of Mediastinum

thoracic inlet

2

Thoracic Inlet

T1, rib 1, suprasternal notch

3

Inferior Border of Mediastinum

thoracic outlet

4

thoracic outlet

T12, diaphragm, xiphoid process

5

Lateral Border of Mediastinum

mediastinal parietal pleura

6

Superior Mediastinum

above horizontal plane btwn sternal angle and T4-T% disc

A-P btwn manubrium and T1-T4

7

Inferior Mediastinum

btwn body and xyphoid process of sternum and T-5 through T-12

8

Anterior Mediastinum

(Inf subdiv)

smallest, btwn pericardium and sternum

9

Middle Mediastinum

(Inf Subdiv)

contains the heart

10

Posterior Mediastinum

(inf subdiv)

btwn heart and T5-T12; contains tubular structures (esophagus, aorta)

11

Thymus Gland

(Anterior M.)

bi-lobed lymphoid organ; mainly in Superior M.

fatty remnant in adults

12

Lymph Nodes

(Ant. M.)

potential site of tumor metastases

13

Middle Mediastinum Contents

Heart (w/in Pericardial Sac)
Ascending Aorta
Pulmonary Trunk
Seven Veins (SVC, Azygos, IVC, 4 PVs)
Phrenic Nerve
Pericardiacophrenic Artery
Mediastinal Lymph Nodes

14

Pericardium

membranous sac composed of outer fibrous membrane and inner serous membrane

15

Fibrous Pericardium

conical, inelastic, limits movement of heart

16

Apex of Fibrous Pericardium

pierced by Asc Aorta, SVC, Pulm Trunk; fused with their tunica adventitia

17

Base of Fibrous Pericardium

fused with central tendon of diaphragm; (respiratory movements affect it)

pierced by IVC

18

Posterior of Fibrous Pericardium

pierced by 4 Pulm Veins; fused with their tunica adventitia

19

Anterior of Fibrous Pericardium

tethered to sternum through sternopericardial ligaments

20

Cardiac tamponade

fluid in pericardial sac from torn heart or coronary vessel causes impaired beating due to external fluid pressure

21

pericardial paracentesis

tx for cardiac tamponade

1) insert needle parasternally into LT 5/6 ICS
2) immed to LT of Xiphoid and angled post. and superiorly at 45*

22

Rt superior border of fibrous pericardium

extends to level of 2 costal cartilage (sternal angle)

23

Rt superior border of heart

extends to level of 3 costal cartilage

24

embryology of fibrous pericardium

derived from body wall of somatic mesoderm of lateral plate

25

Serous pericardium

composed of two layers, pleural and visceral
forms coelomic lining of pericardial cavity

26

Parietal layer of serous pericardium

lines inner surface of fibrous pericardium, inseparable from it

27

visceral layer of serous pericardium

located on outer surface of heart, cont. with parietal layer of serous pericardium by reflecting onto great vessels

28

epicardium of heart

visceral layer of pericardium + subserous cT

29

Pericardial cavity

potential space btwn serious parietal/visceral pericardia
contains serous fluid

30

transverse pericardial sinus

(region of pericardial cavity)

portion btwn SVC (post), AA/PT (ant), SPVv (inf.)

formed by reflections of serous pericardium on above vessels

31

surgical landmark btwn SVC and PT/AA

transverse pericardial sinus

32

Oblique pericardial sinus

blind space of pericardial cavity btwn LA and post. wall of pericardial sac

reflection of serous pericardium from RA on SVC/IVC and LA on 4PVv

33

Division of Intraembryonic Coelom Step 1

continuous space in the lateral mesoderm

34

Division of Intraembryonic Coelom Step 2

end of wk 3, horseshoe shaped cavity in the trilaminar embryo prior to head/tail/lat folding

35

Division of Intraembryonic Coelom Step 3

lateral folding brings L and R sides of horseshoe together to form 1 coelom

36

Division of Intraembryonic Coelom Step 4

The pleuropericardial membrane septae and the thoracic diaphragm septae develop which divide coelom into pleural, pericardial, and peritoneal cavities

37

Pleuropericardial membrane

paired layers of somatic mesoderm that isolate the pleural cavities from the pericardial cavities

38

pleuropericardial membrane formation step 1

splitting off of inner layer of somatic mesoderm from the body wall due to rapid enlargement of developing lungs and future pleural cavities

39

pleuropericardial membrane formation step 2

fuse to each other to form the definitive fibrous pericardium, which surrounds newly partitioned pericardial cavity

40

pleuropericardial membrane innerv

phrenic nerves, lies btwn fibrous pericardium and mediastinal pleura

41

Thoracic diaphragm

separates the pleural and pericardial cavities from peritoneal cavities

42

What fuse together to form diaphragm?

septum transversum, paired pleuroperitoneal membranes, dorsal mesentery of the esophagus, myoblasts from somatic mesoderm of body wall

43

septum transversum

plate of mesoderm in ventral part of embryo that forms the central tendon of the diaphragm.

incompletely separates thoracic cavity from abdominal cavity

44

R and L pleuroperitoneal canals

(septum transversum)

spaces that link thoracic and ab coloemic cavities, loc. along foregut

45

pleuroperitoneal membranes

paired layers of somatic mesoderm located at caudal border of pleural cavities

46

pleuroperitoneal membrane formation

splitting of inner layer of somatic mesoderm from the body wall as the lungs enlarge (more caudal than pleuropericardial)

47

how are the pleuroperitoneal cavities closed?

pleuroperitoneal membrane fuses with septum transversum and dorsal mesentery of the esophagus

48

dorsal mesentery of the esophagus

forms the crura of the diaphragm

invaded by myoblasts

49

myoblasts from the somatic mesoderm of body wall

cont. to muscles of diaphragm

50

Diaphragm formation step 1

septum transversum lies at level of cervical somites and nerve fibers of C3-C5 grow into it

51

Diaphragm formation step 2

descent of diaphragm to L1 result of rapid growth of CNS in dorsal embryo pushing it

52

Diaphragm formation step 3

phrenic nerve dragged inferiorly with the ST

53

phrenic n. innerv.

diaphragm muscles

sensory to parietal pleura and parietal peritoneum of central diaphragm

54

intercostal n. innerv.

sensory to parietal pleura and parietal peritoneum of peripheral diaphragm
(pleuroperitoneal membrane derive)

55

hernia

protrusion of structure through tissues that normally contain it

56

Congenital Diaphragmatic Hernia (Foramen of Bochdalek)

hern. of ab organs into pleural cavity due to failure of pleuroperitoneal membrane (LT) to fuse with other contributors of the diaphragm.

Causes compression of lungs, high mortality rate

57

Esophageal Hiatal Hernia

hern. of stomach thru enlarged esophageal hiatus of diaphragm;

reflux due to esophageogastric sphincter being nonfunctional

vomiting when laid on back

58

Parasternal hernia (Foramen of Morgagni)

hern. of ab viscera thru enlarged sternocostal hiatus (surrounds superior epigastric artery)