Mediastinum/Pericardial Cavity Development Flashcards Preview

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

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

Superior Border of Mediastinum

A

thoracic inlet

2
Q

Thoracic Inlet

A

T1, rib 1, suprasternal notch

3
Q

Inferior Border of Mediastinum

A

thoracic outlet

4
Q

thoracic outlet

A

T12, diaphragm, xiphoid process

5
Q

Lateral Border of Mediastinum

A

mediastinal parietal pleura

6
Q

Superior Mediastinum

A

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

A-P btwn manubrium and T1-T4

7
Q

Inferior Mediastinum

A

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

8
Q

Anterior Mediastinum

A

(Inf subdiv)

smallest, btwn pericardium and sternum

9
Q

Middle Mediastinum

A

(Inf Subdiv)

contains the heart

10
Q

Posterior Mediastinum

A

(inf subdiv)

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

11
Q

Thymus Gland

A

(Anterior M.)

bi-lobed lymphoid organ; mainly in Superior M.

fatty remnant in adults

12
Q

Lymph Nodes

A

(Ant. M.)

potential site of tumor metastases

13
Q

Middle Mediastinum Contents

A
Heart (w/in Pericardial Sac)
Ascending Aorta
Pulmonary Trunk
Seven Veins (SVC, Azygos, IVC, 4 PVs)
Phrenic Nerve
Pericardiacophrenic Artery
Mediastinal Lymph Nodes
14
Q

Pericardium

A

membranous sac composed of outer fibrous membrane and inner serous membrane

15
Q

Fibrous Pericardium

A

conical, inelastic, limits movement of heart

16
Q

Apex of Fibrous Pericardium

A

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

17
Q

Base of Fibrous Pericardium

A

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

pierced by IVC

18
Q

Posterior of Fibrous Pericardium

A

pierced by 4 Pulm Veins; fused with their tunica adventitia

19
Q

Anterior of Fibrous Pericardium

A

tethered to sternum through sternopericardial ligaments

20
Q

Cardiac tamponade

A

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

21
Q

pericardial paracentesis

A

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
Q

Rt superior border of fibrous pericardium

A

extends to level of 2 costal cartilage (sternal angle)

23
Q

Rt superior border of heart

A

extends to level of 3 costal cartilage

24
Q

embryology of fibrous pericardium

A

derived from body wall of somatic mesoderm of lateral plate

25
Q

Serous pericardium

A

composed of two layers, pleural and visceral

forms coelomic lining of pericardial cavity

26
Q

Parietal layer of serous pericardium

A

lines inner surface of fibrous pericardium, inseparable from it

27
Q

visceral layer of serous pericardium

A

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

28
Q

epicardium of heart

A

visceral layer of pericardium + subserous cT

29
Q

Pericardial cavity

A

potential space btwn serious parietal/visceral pericardia

contains serous fluid

30
Q

transverse pericardial sinus

A

(region of pericardial cavity)

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

formed by reflections of serous pericardium on above vessels

31
Q

surgical landmark btwn SVC and PT/AA

A

transverse pericardial sinus

32
Q

Oblique pericardial sinus

A

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
Q

Division of Intraembryonic Coelom Step 1

A

continuous space in the lateral mesoderm

34
Q

Division of Intraembryonic Coelom Step 2

A

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

35
Q

Division of Intraembryonic Coelom Step 3

A

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

36
Q

Division of Intraembryonic Coelom Step 4

A

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

37
Q

Pleuropericardial membrane

A

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

38
Q

pleuropericardial membrane formation step 1

A

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

39
Q

pleuropericardial membrane formation step 2

A

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

40
Q

pleuropericardial membrane innerv

A

phrenic nerves, lies btwn fibrous pericardium and mediastinal pleura

41
Q

Thoracic diaphragm

A

separates the pleural and pericardial cavities from peritoneal cavities

42
Q

What fuse together to form diaphragm?

A

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

43
Q

septum transversum

A

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

incompletely separates thoracic cavity from abdominal cavity

44
Q

R and L pleuroperitoneal canals

A

(septum transversum)

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

45
Q

pleuroperitoneal membranes

A

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

46
Q

pleuroperitoneal membrane formation

A

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

47
Q

how are the pleuroperitoneal cavities closed?

A

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

48
Q

dorsal mesentery of the esophagus

A

forms the crura of the diaphragm

invaded by myoblasts

49
Q

myoblasts from the somatic mesoderm of body wall

A

cont. to muscles of diaphragm

50
Q

Diaphragm formation step 1

A

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

51
Q

Diaphragm formation step 2

A

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

52
Q

Diaphragm formation step 3

A

phrenic nerve dragged inferiorly with the ST

53
Q

phrenic n. innerv.

A

diaphragm muscles

sensory to parietal pleura and parietal peritoneum of central diaphragm

54
Q

intercostal n. innerv.

A

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

55
Q

hernia

A

protrusion of structure through tissues that normally contain it

56
Q

Congenital Diaphragmatic Hernia (Foramen of Bochdalek)

A

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
Q

Esophageal Hiatal Hernia

A

hern. of stomach thru enlarged esophageal hiatus of diaphragm;

reflux due to esophageogastric sphincter being nonfunctional

vomiting when laid on back

58
Q

Parasternal hernia (Foramen of Morgagni)

A

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