GI session 2

Question 1

peritoneal cavity

Answer 1

potential space between parietal and visceral layers of peritoneum

Question 2

parietal peritoneum

Answer 2

lines inner surface of abdominal and pelvic wall

Question 3

subdivisions of peritoneal cavities

Answer 3

greater sac and smaller lesser sac/omental bursa

Question 4

foramen of Winslow

Answer 4

epiploic foramen. connects greater sac to lesser sac

Question 5

subdivisions of greater sac

Answer 5

supracolic and infracolic compartment by transverse colon and transverse mesocolon

Question 6

falciform ligament

Answer 6

double-layered fold of peritoneum
extends from umbilicus onto liver holding a cord-like ligamentum teres in free edge
right layer covers right lobe of liver, reflected onto diaphragm as coronary ligament
left layer encloses the left lobe, reflected onto the diaphragm as the left triangular ligament

Question 7

lesser omentum

Answer 7

two layers
lesser curvature of stomach, first part of duodenum
right free border - common bile duct, hepatic artery and portal vein

Question 8

split of omentum

Answer 8

along the lesser curvature, it splits to enclose stomach

along greater curvature, it reforms again as greater omentum

Question 9

two layers from greater curvature

Answer 9

pass down as anterior two layers of greater omentum and fold on themselves to go upwards and backwards as 2 posterior layers

Question 10

split of posterior layers of greater curvature

Answer 10

enclose transverse colon and continue onto anterior aspect of pancrease as transverse mesocolon

Question 11

upper posterior layer of greater curvature

Answer 11

continues as parietal peritoneum of posterior abdominal wall and lining the diaphragm to be reflected back onto liver

Question 12

lower layer from attachment of transverse mesocolon

Answer 12

continues downwards as parietal peritoneum of lower part of posterior abdominal wall onto pelvic viscera - becomes parietal peritoneum of anterior abdominal wall

Question 13

where is the parietal peritoneum of the posterior abdominal wall interrupted?

Answer 13

reflected to enclose jejunum and ileum - forming mesentry of small intestine
reflected to enclose sigmoid colon forming sigmoid mesocolon - connects to abdominal and pelvic wall

Question 14

root of mesentry

Answer 14

line of attachment of mesentery to posterior abdominal wall

Question 15

where is the parietal peritoneum derived from?

Answer 15

somatic mesoderm

Question 16

parietal peritoneum innervation

Answer 16

same somatic nerve supply as the region it supplies - pain is well localised. sensitive to pressure, pain, laceration and temperature

Question 17

where is the visceral peritoneum derived from?

Answer 17

splanchnic mesoderm

Question 18

visceral peritoneum innervation

Answer 18

same autonomic nerve supply as the viscera it covers. pain is poorly localised. it’s sensitive to stretch and chemical irritation.

Question 19

pain from visceral peritoneum

Answer 19

dermatomes - areas of skin supplied by same sensory ganglia and spinal cord segments as the nerve fibres innervating the viscera

Question 20

intraperitoneal organs

Answer 20

enveloped by visceral peritoneum, anteriorly and posteriorly. stomach, liver and spleen

Question 21

retroperitoneal organs

Answer 21

only covered by parietal peritoneum anteriorly.

Question 22

primarily retroperitoneal organs

Answer 22

developed and remain outside of parietal peritoneum. oesophagus, rectum and kidneys

Question 23

secondarily retroperitoneal organs

Answer 23

initially intraperitoneal, suspended by mesentery. became retroperitoneal as mesentry fused with posterior abdominal wall. ascending and descending colon

Question 24

examples of retroperitoneal organs

Answer 24

suprarenal (adrenal) glands
aorta/ivc
duodenum
pancreas (except tail)
ureters
colon (ascending and descending)
kidneys
oesophagus 
rectum

Question 25

how does the peritoneum perform its functions?

Answer 25

develops into a highly folded, complex structure

Question 26

mesentry

Answer 26

double layer of visceral peritoneum. connects intraperitoneal organ to posterior abdominal wall. pathway for nerves, blood vessels and lymphatics. mesentry of small intestine. transverse and sigmoid mesocolons, mesoappendix

Question 27

omenta

Answer 27

sheets of visceral peritoneum extending from the stomach and proximal parts of the duodenum to other abdominal organs

Question 28

greater omentum

Answer 28

4 layers of visceral peritoneum. from greater curvature of stomach and proximal part of the duodenum, folds back up and attaches to anterior surface of transverse colon. can migrate to infected viscera or surgical disturbance

Question 29

lesser omentum

Answer 29

double layer of visceral peritoneum. attaches from lesser curvature of the stomach and proximal part of duodenum to the liver.

Question 30

peritoneal fluid

Answer 30

water, electrolytes, leukocytes and antibodies. acts as lubricant, allowing free movement of abdominal viscera and antibodies to fight infection.

Question 31

potential space

Answer 31

when filled with a thin film of fluid, it's a potential space as excess fluid can accumulate in it - ascites

Question 32

greater sac

Answer 32

larger portion of cavity. divided into mesentry of transverse colon: supracolic and infracolic compartments

Question 33

supracolic compartment

Answer 33

above transverse mesocolon. contains stomach, liver, spleen

Question 34

infracolic compartment

Answer 34

lies below transverse mesocolon. contains small intestine, ascending and descending colon. divided into left and right infracolic spaces by mesentry of small intestine.

Question 35

how are supracolic and infracolic compartments connected?

Answer 35

paracolic gutters - lie between posterolateral abdominal wall and lateral aspect of ascending or descending colon

Question 36

lesser sac

Answer 36

omental bursa. lies posteriorly to stomach and lesser omentum. allows stomach to move freely. connected to greater sac through epiploic foramen (posterior to free edge).

Question 37

where is superfluous fluid most likely to collect?

Answer 37

when sitting or standing up - most inferior portion of peritoneal cavity

Question 38

rectovesical pouch in males

Answer 38

double folding of peritoneum between rectum and bladder. completely closed.

Question 39

two pelvic areas of note in females

Answer 39

``` rectouterine pouch (of Douglas) vesicouterine pouch ```

Question 40

rectouterine pouch (of Douglas)

Answer 40

double folding of peritoneum between rectum and posterior wall of the uterus

Question 41

vesicouterine pouch

Answer 41

double folding of peritoneum between anterior surface of uterus and bladder

Question 42

enclosure of female peritoneal cavity

Answer 42

uterine tubes open into it. | potential pathway between genital tract and abdominal cavity - infection.

Question 43

why is infection of peritoneal cavity rare in females?

Answer 43

mucus plug in external os of uterus preventing passages of pathogens - allows sperm.