Anatomy: Abdomen IV - Peritoneum, Omentum, Epiploic Spaces
These flashcards focus on the embryological development of the peritoneal cavity and gut. They explain how rapid gut growth is accommodated by the formation of the peritoneal cavity and highlight the physiological herniation of the midgut into the umbilical cord due to space limitations. Key processes such as gut rotation around the superior mesenteric artery are also addressed, crucial for understanding normal and abnormal abdominal development.
Embryology of the Peritoneal Cavity:
“By the end of the 10th week, the gut is much longer than the body that contains it.”
What 2 things are needed for this increase in length to occur?
gut needs freedom of movement relative to the body wall
maintain the connection with body wall necessary for innervation and blood supply
Rate to track your progress ✦
Key Terms
Embryology of the Peritoneal Cavity:
“By the end of the 10th week, the gut is much longer than the body that contains it.”
What 2 things are needed for this increase in length to occur?
gut needs freedom of movement relative to the body wall
maintain the c...
The embryological growht of the gut is accomodated by what?
development of the peritoneal serous cavity within the trunk
(hous...
During embryonic growth, why does the gut extend outside of the trunk for a period of time?
rate of growth of the gut initially surpasses the development of adequate space within the trunk
When does the midgut herniate into the umbilical chord?
early in week 5
The primary rotation of the herniated midgut occurs around what structure in the umbilical cord?
superior mesenteric srtery
The herniated midgut returns to the trunk by what time?
by the end of week 10
(by week 11)
During early development, the embryonic body cavity (intraembryonic coelom) is lined with what tissue?
What peritoneal structre is derived from this tissue?
mesoderm
the parietal peritoneum is derived from mesoderm
- ...
retroperitoneal structures…
…protrude only partially into the peritoneal cavity (partially covered by visceral peritoneum)
Intraperitoneal structures…
…protrude completely into the peritoneal cavity (completely covered by viseral peritoneum)
connected to abdominal wall by mesentery
In general, viscera that vary relatively little in size and shape are….
retroperitoneal
In general, viscera that undergo changes in size/shape (filling/emptying, peristalsis) are…
invested with visceral peritoneum (intraperitoneal)
they are mobile to some degree (b/c of mesentaries)
The vessels & nerves of intraperitoneal organs remain connected to what?
their extraperitoneal sources
What major change occurs in regards to the peritoneal cavity space from embryonic development to post-natal life?
changes from the 1. peritoneal cavity
(entire primor...
As a result of growing organs, several parts of the gut come to lie against the posterior abdominal wall. What does this cause?
their posterior mesenteries become gradually reduced because of pressure from overlying organs
What happens to the part of the visceral peritoneum lying against the body wall?
fuses with the parietal peritoneum of the body wall
During development, the peritoneal cavity is divided into what sections?
greater and lesser peritoneal sacs
A surgical incision through the anterolateral abdominal wall enters the main, larger part of the peritoneal cavity. Which sac is this?
the greater sac
What sac, also known as the omental bursa, lies posterior to the stomach and lesser omentum?
The lesser sac
The transverse mesocolon (mesentery of the transverse colon) divides the abdominal cavity into what 2 compartments?
What does each compartment contain?
supracolic compartment
- stomach
The infracolic compartment lies posterior to what structure?
It is divided into what 2 spaces by the mesentery of the small intestine?
the greater omentum
right infracolic space
How does free communication occur between the supracolic and the infracolic compartments?
through the paracolic gutters
(grooves between the lateral aspect of ascending or descending colon ...
What is the omental bursa?
an extensive sac-like cavity that lies posterior to the stomach, lesser omentum, and adjacent structures
What are the names and locations of the 2 recesses of the omental bursa?
superior recess
limited superiorly by diaphragm + posterior layers of ...
What permits free movement of the stomach on the structures posterior and inferior to it?
How does it do this?
The omental bursa
anterior and posterior walls of omental bursa slide ...
Most of the inferior recess of the bursa becomes sealed off from the main part posterior to the stomach after what occurs?
adhesion of the anterior + posterior layers of the greater omentum
The omental bursa communicates with the greater peritoneal sac through what structure?
How can this structure be found?
the omental foramen (epiploic foramen)
opening situated posterior to free edge of lesser omentum (hepatoduodenal lig...
What are the superior, inferior, anterior and posterior borders of the omental foramen?
Superiorly = liver, covered with visceral peritoneum
Inferiorly = superior (first) part of the duodenum
...What results form a perforation of the posterior wall of the stomach?
passage of its fluid contents into the omental bursa
What pathology can also result in the passage of fluid into the bursa, forming a pancreatic pseudo-cyst?
An inflamed or injured pancreas
What uncommon abnormality may enter the omental bursa and be strangulated by the edges of the foramen?
How is this corrected?
a loop of small intestine may pass through the omental foramen
swollen intestine must be de...
During cholecystectomy (removal of the gallbladder), what must be done to the cystic artery?
What may happen to the cystic artery during this procedure?
cystic artery must be ligated or clamped and then severed
Sometimes accidentally severed before it...
What can be done if the cystic artery is severed before it is properly ligated?
can control the hemorrhage by compressing the hepatic artery as it traverses the hepatoduodenal ligament
index finger is pla...
The principal viscera of the abdomen are the…?
terminal part of esophagus + stomach
intestines
spleen
pancreas
liver
<...
What abdominal viscera almost fill the domes of the diaphragm?
Where do they receive protection from?
liver, stomach, spleen
protected by lower thoracic cage
What ligament normally attaches along a continuous line to the anterior abdominal wall as far inferiorly as the umbilicus and divides the liver superficially into right and left lobes?
falciform ligament
The fat-laden greater omentum, when in its typical position, conceals almost all of …?
the intestine
The gallbladder projects inferior to …?
the sharp border of the liver
Food passes from the mouth and pharynx through the ___ to the stomach, where it mixes with ______________?
esophagus
gastric secretions -
Digestion mostly occurs in which areas?
the stomach and duodenum
Peristalsis
series of ring-like contraction waves that begin around the middle of stomach + move slowly toward the pylorus
The stomach is continuous with what inferior structure?
This structure receives the openings of the ducts from _________?
the duodenum
- pancreas + liver (major glands of the digestive tract)
Absorption of chemical compounds occurs principally in what area?
This consists of what 3 parts?
small intestine
(coiled 5- to 6-m-long tube)
duodenum
jejunum
ileum
What occurs in the jejunum and ileum but is not forceful unless an obstruction is present?
Peristalsis
The large intestine consists of what structures?
cecum
receives the terminal part of the ileum
appendix
colon
ascending, ...
Most reabsorption of water occurs in what part fo the large intestine?
Feces form in what parts of the large intestine, before accumulating in the rectum?
water absorption = ascending colon
Fecal formation = descending + sigmoid colon
The arterial supply to the alimentary tract is from what source?
What are the three major branches from this that supply the gut?
abdominal aorta
celiac trunk
superior mesenteric arteries
inferior mesenteric arteries...
Which venous system collects blood from the abdominal part of the alimentary tract, pancreas, spleen, + most of the gallbladder?
portal venous system
The portal vein is formed by the union of what 2 veins?
It carries blood from the abdominal part of the alimentary tract and some viscera to where?
superior mesenteric + splenic veins
to the liver
Esophagus
muscular tube [approximately 25 cm long]
average diameter of 2 cm
conveys food from the pharynx to the stomac...
What are the 3 constrictions of the esophagus?
Cervical constriction:
beginning at pharyngoesophageal junction, approx 15 cm from incisor teeth
caus...
What is the clinical importance of an awareness of the diaphragmatic constrictions?
passing instruments through the esophagus into the stomach
viewing radiographs of patients who are experiencing dysphagia (d...
The esophagus follows the curve of what?
(as it descends through the neck and mediastinum)
Has internal circular and external longitudinal layers of muscle.
In its superior third, the external layer consists of voluntary striated muscle; the inferior third is composed of smooth muscle, and the middle third is made up of both types of muscle.
vertebral column
musculature of the esophagus
internal circular + external longitudinal layers of muscle
superior 1/3 = external layer c...
Where does the esophagus pass into the abdomen?
elliptical esophageal hiatus in muscular right crus of the diaphragm
(just to left of med...
Where does the esophagus terminate inferiorly?
enters stomach at cardial orifice of the stomach
(left of midline at 7th left costal cartilage + T11 vertebra level)
The esophagus is encircled distally by what structre?
esophageal nerve plexus
The esophagus is attached to the margins of the esophageal hiatus in the diaphragm by …?
phrenicoesophageal ligament
(extension of inferior diaphragmatic fascia)
permits independent movement of diaph...
What causes food to pass through the esophagus rapidly?
peristaltic action (aided by gravity)
The abdominal part of the esophagus is located where?
How long is it?
from esophageal hiatus --> cardial orifice of the stomach
(passing anteriorly + left as it descends)*
1.25...
The anterior surface of the esophagus is covered with what?
peritoneum of the greater sac
(continuous with that covering the anterior surface of the stomach)
The posterior surface of the esophagus is covered with what?
peritoneum of the omental bursa
(continuous with that covering the posterior surface of the stomach)
The esophagus fits into a groove on the posterior (visceral) surface of what organ?
the liver
The right border of the esophagus is continuous with the ______________?
The left border is separated from the fundus of the stomach by the ______________?
lesser curvature of the stomach
cardial notch
The esophagogastric junction lies where?
left of the T11 vertebra
( on horizontal plane passing through tip of xiphoid process)
@ Z-line
What structure prevents the reflux of gastric contents into the esophagus?
sphincter mechanism
When one is not eating, what happens to the lumen of the esophagus?
normally collapsed superior to the esophagogastric junction to prevent food or stomach juices from regurgitating into the ...
The arterial supply of the abdominal part of the esophagus is from what 2 arteries?
left gastric artery (branch of celiac trunk)
left inferior phrenic artery
The venous drainage from the submucosal veins of the abdominal part of the esophagus is to which 2 venous systems (through which veins)?
portal venous system --> left gastric vein
systemic venous system --> esophageal veins entering azygo...
The lymphatic drainage of the abdominal part of the esophagus is into which lymph nodes?
left gastric lymph nodes
(efferent lymphatic vessels from these nodes drain mainly to celiac lymph nodes)
The esophagus is innervated by the (1.)___________ plexus, formed by the (2.)_______ trunks and the (3.)___________ trunks via the (4.)______________ nerves and (5.)___________ plexuses around the left gastric and inferior phrenic arteries.
1 - esophageal nerve plexus
2 - vagal trunks
(becoming anterior and posterior gastric branches)
Because the submucosal veins of the inferior esophagus drain to both the portal and the systemic venous systems, they constitute a ___________________?
portosystemic anastomosis
What happens in portal hypertension (an abnormally increased blood pressure in the portal venous system)?
blood is unable to pass through the liver via the portal vein, causing a reversal of flow in the esophageal tributary
The large volume of blood in portal hypertension causes the submucosal veins to enlarge markedly, forming what?
esophageal varices
What life-threatening occurance can result from esophageal varices?
Who is most likely to develop varacies?
varicies may rupture + cause severe hemorrhage that is life-threatening and difficult to control surgical...
This is the most common type of esophageal discomfort or substernal pain:
(clinical + common name)
Pyrosis or heartburn
Pyrosis:
The burning sensation in the abdominal part of the esophagus is usually the result of …?
regurgitation of small amounts of food or gastric fluid into the lower esophagus (gastroesophageal reflux disorder)
which type of hernia may be associated with pyrosis?
hiatal (hiatus) hernia
Related Flashcard Decks
| Term | Definition |
|---|---|
Embryology of the Peritoneal Cavity: “By the end of the 10th week, the gut is much longer than the body that contains it.” What 2 things are needed for this increase in length to occur? |
|
The embryological growht of the gut is accomodated by what? | development of the peritoneal serous cavity within the trunk (houses the increasingly lengthy + convoluted gut in a relatively compact space) |
During embryonic growth, why does the gut extend outside of the trunk for a period of time? | rate of growth of the gut initially surpasses the development of adequate space within the trunk |
When does the midgut herniate into the umbilical chord? | early in week 5 |
The primary rotation of the herniated midgut occurs around what structure in the umbilical cord? | superior mesenteric srtery |
The herniated midgut returns to the trunk by what time? | by the end of week 10 (by week 11) |
During early development, the embryonic body cavity (intraembryonic coelom) is lined with what tissue? What peritoneal structre is derived from this tissue? |
|
retroperitoneal structures… | …protrude only partially into the peritoneal cavity (partially covered by visceral peritoneum) |
Intraperitoneal structures… | …protrude completely into the peritoneal cavity (completely covered by viseral peritoneum)
|
In general, viscera that vary relatively little in size and shape are…. | retroperitoneal |
In general, viscera that undergo changes in size/shape (filling/emptying, peristalsis) are… | invested with visceral peritoneum (intraperitoneal)
|
The vessels & nerves of intraperitoneal organs remain connected to what? | their extraperitoneal sources |
What major change occurs in regards to the peritoneal cavity space from embryonic development to post-natal life? | changes from the 1. peritoneal cavity (entire primordial gut is suspended) to 2. potential space between the parietal + visceral layer (organs have grown therefore space has been reduced) |
As a result of growing organs, several parts of the gut come to lie against the posterior abdominal wall. What does this cause? |
|
What happens to the part of the visceral peritoneum lying against the body wall? | fuses with the parietal peritoneum of the body wall |
During development, the peritoneal cavity is divided into what sections? | greater and lesser peritoneal sacs |
A surgical incision through the anterolateral abdominal wall enters the main, larger part of the peritoneal cavity. Which sac is this? | the greater sac |
What sac, also known as the omental bursa, lies posterior to the stomach and lesser omentum? | The lesser sac |
The transverse mesocolon (mesentery of the transverse colon) divides the abdominal cavity into what 2 compartments? What does each compartment contain? | supracolic compartment - stomach
infracolic compartment
|
The infracolic compartment lies posterior to what structure? It is divided into what 2 spaces by the mesentery of the small intestine? | the greater omentum
|
How does free communication occur between the supracolic and the infracolic compartments? | through the paracolic gutters (grooves between the lateral aspect of ascending or descending colon + posterolateral abdominal wall) |
What is the omental bursa? | an extensive sac-like cavity that lies posterior to the stomach, lesser omentum, and adjacent structures |
What are the names and locations of the 2 recesses of the omental bursa? | superior recess limited superiorly by diaphragm + posterior layers of coronary ligament of liver inferior recess between superior parts of the layers of greater omentum |
What permits free movement of the stomach on the structures posterior and inferior to it? How does it do this? | The omental bursa anterior and posterior walls of omental bursa slide smoothly over each other |
Most of the inferior recess of the bursa becomes sealed off from the main part posterior to the stomach after what occurs? | adhesion of the anterior + posterior layers of the greater omentum |
The omental bursa communicates with the greater peritoneal sac through what structure? How can this structure be found? | the omental foramen (epiploic foramen)
(usually admits two fingers) |
What are the superior, inferior, anterior and posterior borders of the omental foramen? | Superiorly = liver, covered with visceral peritoneum Inferiorly = superior (first) part of the duodenum Anteriorly = hepatoduodenal ligament (free edge of the lesser omentum), containing portal vein, hepatic artery, + bile duct Posteriorly = IVC + right crus of diaphragm (covered anteriorly with parietal peritoneum - retroperitoneal) |
What results form a perforation of the posterior wall of the stomach? | passage of its fluid contents into the omental bursa |
What pathology can also result in the passage of fluid into the bursa, forming a pancreatic pseudo-cyst? | An inflamed or injured pancreas |
What uncommon abnormality may enter the omental bursa and be strangulated by the edges of the foramen? How is this corrected? | a loop of small intestine may pass through the omental foramen
|
During cholecystectomy (removal of the gallbladder), what must be done to the cystic artery? What may happen to the cystic artery during this procedure? | cystic artery must be ligated or clamped and then severed
|
What can be done if the cystic artery is severed before it is properly ligated? |
|
The principal viscera of the abdomen are the…? |
|
What abdominal viscera almost fill the domes of the diaphragm? Where do they receive protection from? | liver, stomach, spleen
|
What ligament normally attaches along a continuous line to the anterior abdominal wall as far inferiorly as the umbilicus and divides the liver superficially into right and left lobes? | falciform ligament |
The fat-laden greater omentum, when in its typical position, conceals almost all of …? | the intestine |
The gallbladder projects inferior to …? | the sharp border of the liver |
Food passes from the mouth and pharynx through the ___ to the stomach, where it mixes with ______________? | esophagus
|
Digestion mostly occurs in which areas? | the stomach and duodenum |
Peristalsis |
|
The stomach is continuous with what inferior structure? This structure receives the openings of the ducts from _________? | the duodenum - pancreas + liver (major glands of the digestive tract) |
Absorption of chemical compounds occurs principally in what area? This consists of what 3 parts? | small intestine (coiled 5- to 6-m-long tube)
|
What occurs in the jejunum and ileum but is not forceful unless an obstruction is present? | Peristalsis |
The large intestine consists of what structures? | cecum receives the terminal part of the ileum appendix colon ascending, transverse, descending + sigmoid rectum anal canal which ends at the anus |
Most reabsorption of water occurs in what part fo the large intestine? Feces form in what parts of the large intestine, before accumulating in the rectum? | water absorption = ascending colon Fecal formation = descending + sigmoid colon |
The arterial supply to the alimentary tract is from what source? What are the three major branches from this that supply the gut? | abdominal aorta
|
Which venous system collects blood from the abdominal part of the alimentary tract, pancreas, spleen, + most of the gallbladder? | portal venous system |
The portal vein is formed by the union of what 2 veins? It carries blood from the abdominal part of the alimentary tract and some viscera to where? | superior mesenteric + splenic veins
|
Esophagus |
|
What are the 3 constrictions of the esophagus? | Cervical constriction:
- clinically = upper esophageal sphincter Thoracic (broncho-aortic) constriction:
Diaphragmatic constriction:
|
What is the clinical importance of an awareness of the diaphragmatic constrictions? |
|
The esophagus follows the curve of what? (as it descends through the neck and mediastinum) Has internal circular and external longitudinal layers of muscle. In its superior third, the external layer consists of voluntary striated muscle; the inferior third is composed of smooth muscle, and the middle third is made up of both types of muscle. | vertebral column |
musculature of the esophagus |
|
Where does the esophagus pass into the abdomen? |
(just to left of median plane at T10 vertebra level) |
Where does the esophagus terminate inferiorly? | enters stomach at cardial orifice of the stomach (left of midline at 7th left costal cartilage + T11 vertebra level) |
The esophagus is encircled distally by what structre? | esophageal nerve plexus |
The esophagus is attached to the margins of the esophageal hiatus in the diaphragm by …? | phrenicoesophageal ligament (extension of inferior diaphragmatic fascia)
|
What causes food to pass through the esophagus rapidly? | peristaltic action (aided by gravity) |
The abdominal part of the esophagus is located where? How long is it? |
|
The anterior surface of the esophagus is covered with what? | peritoneum of the greater sac (continuous with that covering the anterior surface of the stomach) |
The posterior surface of the esophagus is covered with what? | peritoneum of the omental bursa (continuous with that covering the posterior surface of the stomach) |
The esophagus fits into a groove on the posterior (visceral) surface of what organ? | the liver |
The right border of the esophagus is continuous with the ______________? The left border is separated from the fundus of the stomach by the ______________? |
|
The esophagogastric junction lies where? | left of the T11 vertebra ( on horizontal plane passing through tip of xiphoid process) @ Z-line (jagged line where mucosa abruptly changes fr. esophageal to gastric mucosa) immediately inferior to: "physiological inferior esophageal sphincter" (contracts and relaxes) |
What structure prevents the reflux of gastric contents into the esophagus? | sphincter mechanism |
When one is not eating, what happens to the lumen of the esophagus? |
|
The arterial supply of the abdominal part of the esophagus is from what 2 arteries? | left gastric artery (branch of celiac trunk) left inferior phrenic artery |
The venous drainage from the submucosal veins of the abdominal part of the esophagus is to which 2 venous systems (through which veins)? | portal venous system --> left gastric vein systemic venous system --> esophageal veins entering azygos vein |
The lymphatic drainage of the abdominal part of the esophagus is into which lymph nodes? | left gastric lymph nodes (efferent lymphatic vessels from these nodes drain mainly to celiac lymph nodes) |
The esophagus is innervated by the (1.)___________ plexus, formed by the (2.)_______ trunks and the (3.)___________ trunks via the (4.)______________ nerves and (5.)___________ plexuses around the left gastric and inferior phrenic arteries. | 1 - esophageal nerve plexus 2 - vagal trunks (becoming anterior and posterior gastric branches) 3 - thoracic sympathetic trunks 4 - greater (abdominopelvic) splanchnic nerves 5 - periarterial plexuses |
Because the submucosal veins of the inferior esophagus drain to both the portal and the systemic venous systems, they constitute a ___________________? | portosystemic anastomosis |
What happens in portal hypertension (an abnormally increased blood pressure in the portal venous system)? | blood is unable to pass through the liver via the portal vein, causing a reversal of flow in the esophageal tributary |
The large volume of blood in portal hypertension causes the submucosal veins to enlarge markedly, forming what? | esophageal varices |
What life-threatening occurance can result from esophageal varices? Who is most likely to develop varacies? |
|
This is the most common type of esophageal discomfort or substernal pain: (clinical + common name) | Pyrosis or heartburn |
Pyrosis: The burning sensation in the abdominal part of the esophagus is usually the result of …? | regurgitation of small amounts of food or gastric fluid into the lower esophagus (gastroesophageal reflux disorder) |
which type of hernia may be associated with pyrosis? | hiatal (hiatus) hernia |