Peritoneum

Question 0

What are the subdivisions of peritoneum?

Answer 0

1. Parietal layer

2. Visceral layer (serosa)

Question 1

What is peritoneum?

Answer 1

A serous membrane lining the cavity abdomen and covering the abdominal organs

Question 2

Describe the parietal layer of the peritoneum

Answer 2

Lines the body wall and has abundant pain fibers via nerves from the body wall

Question 3

Describe the visceral layer (serosa) of the peritoneum

Answer 3

Covers viscera and lacks pain fibers

Question 4

What is between parietal and visceral layers of the peritoneum?

Answer 4

peritoneal cavity

Question 5

Define mesentery

Answer 5

Double layers of visceral peritoneum. So they lack pain fibers
They are called reflections: part of peritoneal lining that is not right against the body wall or the organ. It is between organs. Most of the time it is suspending an organ from the body wall.

Question 6

Why are mesenteries important?

Answer 6

They keep things in place, maintain relationships among structures in the abdominal cavity. Transmit major vessels and nerves.

Question 7

What are intraperitoneal organs?

Answer 7

organs covered on most sides by visceral peritoneum

Suspended by mesentery from the body wall

Question 8

What are retroperitoneal organs?

Answer 8

Organs that lie deep to the parietal peritoneum and are covered by parietal peritoneum on one side only (so they do not have any mesentery)

Question 9

What are examples of intraperitoneal organs-have a mesentery and are completely covered by the peritoneum?

Answer 9

In the abdominal peritoneal cavity:
Stomach
Small intestine
Spleen
Liver
Gallbladder
Cecum
Large intestine

Pelvic peritoneal cavity:
Uterus
Ovaries
Uterine tubes

Question 10

What are the retroperitoneal organs?

Answer 10

Primarily:
Kidneys, suprarenal glands, uterine cervix, ureters, gonads, aorta and inferior vena cava
Secondarily:
Duodenum (descending, horizontal, and ascending)
Ascending and descending colon
Pancreas and rectum (upper 2/3)

Question 11

What is the nerve supply to the peritoneum?

Answer 11

Nerves from the adjacent body wall supply parietal peritoneum. The nerves supply pain and vasomotor fibers

Question 12

What is the difference between primarily retroperitoneal and secondarily retroperitoneal?

Answer 12

Secondarily retroperitoneal became retroperitoneal during development

Question 13

What are the three main types of peritoneal reflections in adults?

Answer 13

Mesenteries
Ligaments and folds
Omentum

Question 14

What are peritoneal reflections?

Answer 14

Parts of peritoneal linings that are not against body wall or an organ, but sort of “hangs out” between structures in the abdomen

Question 15

What are mesenteries?

Answer 15

2-layered fold of peritoneum

Question 16

What is THE mesentery?

Answer 16

Attaches the “free” small intestine (jejunum and ileum) to the posterior body wall

Question 17

Define transverse mesocolon

Answer 17

Mesentery of the transverse colon
Holds the transverse colon to the posterior body wall
Fuses with the posterior layer of the greater omentum

Question 18

Define sigmoid mesocolon

Answer 18

Mesentery of the sigmoid colon

Holds the sigmoid colon to the posterior body wall

Question 19

What is mesoappendix?

Answer 19

Mesentery of the vermiform appendix

Question 20

The mesenteries of the duodenum, ascending colon, descending colon and cecum are usually lost during development. Since they are no longer suspended by a mesentery these organs are ________ ________.

Answer 20

Secondarily retroperitoneal

Question 21

Define peritoneal ligaments

Answer 21

May be subdivisions of a larger structure
Usually transmit nerves and vessels
Usually lack connective tissue and are not the same as ligaments that join bones

Question 22

What are some examples of peritoneal ligaments?

Answer 22

Gastrosplenic and splenorenal (lienorenal) ligament

Question 23

Define omentum

Answer 23

(epiploon)

Broad, 2-4 layered sheet of peritoneum that attaches the stomach to other viscera

Question 24

Define lesser omentum

Answer 24

Develops from the ventral mesogastrium (mesentery) Runs from lesser curvature of the stomach to the liver ``` Subdivided into parts: Hepatogastric ligament (stomach to liver) Hepatoduodenal ligament (liver to duodenum) ```

Question 25

Define greater omentum

Answer 25

Develops from the dorsal mesogastrium 4 layers 3 ligaments

Question 26

What are the three ligaments of the greater omentum?

Answer 26

``` Gastrocolic ligament (stomach to transverse colon) Gastrophrenic ligament (stomach to diaphragm)(continuous with phrenicosplenic ligament) Gastrosplenic ligament (stomach to spleen) ```

Question 27

What peritoneal ligaments are associated with the liver?

Answer 27

Coronary ligaments Right and left triangular ligaments Falciform ligament Ligamentum teres hepatis

Question 28

What is a fold?

Answer 28

A ridge or elevation in the peritoneum produced by underlying vessels

Question 29

What are fossae (fossa) or recesses?

Answer 29

Depressions between folds

Question 30

What are examples of folds and fossa?

Answer 30

Superior duodenal fold and fossa (recess) Paraduodenal fossa Inferior duodenal fold and fossa Retroduodenal fossa Fold formed by inferior mesenteric vein posterior to peritoneum

Question 31

Structures coursing through the extraperitoneal tissue form elevations on the interior abdominal wall called what?

Answer 31

Peritoneal umbilical folds

Question 32

What are the umbilical folds?

Answer 32

Median umbilical fold: inferiorly it forms the urachus (anchors the bladder). The fold is midline from bladder Medial umbilical folds (2) - medial umbilical ligaments - obliterated umbilical as Lateral umbilical folds (2) - inferior epigastric vessels - functional aa and vv

Question 33

What are supraumbilical structures located on the internal aspect of the anterior abdominal wall?

Answer 33

Falciform ligament: curved remnant of the ventral mesogastrium Ligamentum teres hepatis: Round ligament of the liver in its lower free border; obliterated umbilical vein

Question 34

Define supravesical fossa

Answer 34

Fossa between the median and medial umbilical folds | Site for supravesical hernias (rare)

Question 35

Define medial inguinal fossa

Answer 35

Fossa between the medial and lateral umbilical folds Site for direct inguinal hernias Also called inguinal triangle

Question 36

Define Lateral inguinal fossa

Answer 36

Fossa lateral to the lateral umbilical folds | Site for indirect inguinal hernias

Question 37

What makes up most of the "potential" space within the abdomen?

Answer 37

The greater sac

Question 38

What are the subdivisions of the greater sac?

Answer 38

The greater sac and be subdivided into supracolic and infracolic regions by the colon and the transverse mesocolon

Question 39

Define supramesocolic (supracolic) region

Answer 39

Superior and anterior to the liver and stomach | Includes hepatorenal and subphrenic spaces and fossae of the anterior wall

Question 40

What are the recesses and fossae of the peritoneal cavity?

Answer 40

Subphrenic recess Subhepatic/hepatorenal recess Rectovesical/rectouterine recess

Question 41

The peritoneal cavity is a (open/closed) potential space between parietal and visceral layers of peritoneum

Answer 41

Closed

Question 42

Define inframesocolic region

Answer 42

Inferior and posterior part of the greater sac Subdivided by mesenteries and "ligaments" Clinically important spaces where intraperitoneal infections spread; phrenicocolic ligament limits the spread of fluid superiorly

Question 43

What are lateral to the ascending and descending colon?

Answer 43

The infracolic compartments right and left paracolic gutters

Question 44

What are the upper and lower parts of the inframesocolic region divided by?

Answer 44

THE mesentery into right and left infracolic spaces

Question 45

The lesser sac (omental bursa) develops as part of the _______

Answer 45

Greater sac

Question 46

How do greater and lesser peritoneal sacs communicate?

Answer 46

Through the epiploic foramen (of winslow)

Question 47

Where is the lesser sac?

Answer 47

Posterior and inferior to the stomach

Question 48

What are the recesses of the lesser sac

Answer 48

Superior recess: posterior to the liver Inferior recess: Potential space between the 2 layers of the gastrocolic ligament Splenic recess: Posterior to and left of the stomach

Question 49

How is the lesser sac clinically important?

Answer 49

Important relationship to the liver, pancreas, stomach and spleen