GI anatomy Flashcards
1
Q
what planes are used to divide the abdomen into quadrants?
A
median + transumbilical
2
Q
which planes are used to divide the abdomen into 9 regions?
A
left and right midclavicular planes, subcostal plane, transtubercular plane
3
Q
what are 9 regions of the abdomen?
A
right hypochondriac, epigastric, left hypochondriac, right lumbar, umbilical, left lumbar, right inguinal, pubic, left inguinal
4
Q
which organs are found in the right hypochondriac region?
A
right lobe of liver, hepatic flexure, right kidney, duodenum, pyloric stomach
5
Q
which organs are found in the left hypochondriac region?
A
stomach, spleen, splenic flexure, left kidney, pancreas
6
Q
which organs are found in the epigastric region?
A
oesophagus, stomach, left lobe of liver, pancreas, transverse colon
7
Q
which organs are found in the right lumbar region?
A
ascending colon, right kidney, duodenum, jejunum
8
Q
which organs are found in the left hypochondriac region?
A
descending colon, left kidney, jejunum, ileum
9
Q
which organs are found in the umbilical region?
A
duodenum, jejunum, ileum,
10
Q
which organs are found in the right inguinal region?
A
caecum, appendix, ileum, right ureter, right ovary/spermatic cord
11
Q
which organs are found in the pubic region?
A
ileum, bladder, (uterus)
12
Q
which organs are found in the left inguinal region?
A
sigmoid colon, left ureter, left ovary/spermatic cord
13
Q
what is the linea alba?
A
midline of rectus abdominis
14
Q
what is the linea semilunaris?
A
the line around the outside of the rectus abdominis
15
Q
where does the RA attach to?
A
pubic crest and xiphoid process and costal cartilages of ribs 5 to 7
16
Q
what type of muscle is RA?
A
paired strap muscle
17
Q
what covers the RA?
A
rectus sheath?
18
Q
what makes up the rectus sheath from deep to superficial?
A
the aperneurosis of transversus abdominis, internal oblique and external oblique muscles
19
Q
where does TA originate from?
A
Iliac crest, inguinal ligament, thoracolumbar fascia, and costal cartilages 7-12
20
Q
which direction do the fibres of TA run?
A
mostly horizontally unless forms part of inguinal canal
21
Q
Where does IO originate from?
A
Inguinal ligament, Iliac crest, thoracolumbar fascia
22
Q
which direction do the fibres of IO run?
A
down and backwards unless forms part of inguinal canal
23
Q
where does EO originate from?
A
eight fleshy digitations from the external surfaces and inferior borders of ribs 5 to 12
24
Q
what does the free edge of External oblique form?
A
inguinal ligament
25
what is the defect in the fibres of EO?
superficial inguinal ring
26
what does the internal thoracic artery bifurcate into?
musculophrenic and superior epigastric arteries
27
what does the musculophernic artery supply?
diaphragm and anterior abdominal wall
28
what does the superior epigastric artery supply?
Rectus abdominis - pierces the rectus sheath
29
where does the inferior epigastric artery come from?
external iliac artery
30
where does the external iliac artery run and what does it give rise to?
runs into the pelvis deep to the inguinal ligament and gives rise to the femoral artery
31
which abdominal artery does the femoral artery give rise to?
superficial epigastric
32
which thoracic nerves supply the abdomen?
continuations of nerves T8-T12
33
which nerves arise from L1 and where do they supply?
ileohypogastric - supplies inguinal region
| lieoinguinal - travels through inguinal canal to innervate parts of the genitalia
34
between which layers do the nerves and arteries of the abdomen run?
transversus abdominis and internal oblique
35
above the umbilicus, list the layers of the PAW from superficial to deep
skin, subcutaneous tissue, external oblique, internal oblique, rectus abdominis, internal ablique, transversus abdominis, transversalis fascia, parietal peritoneum
36
below the umbilicus, list the layers of the PAW from superficial to deep
skin, subcutaneous tissue, external oblique, internal oblique, transversus abdominis, rectus abdominis, transversalis fascia, parietal peritoneum
37
what and where is the arcuate line?
cresent shaped line where the rectus sheath pierces RA. lies 1/3 way between umbilicus and pubic crest. it is also where the inferior epigastric perforates the RA muscle
38
list the bony features of the pelvis that we need to know.
ASIS, pubic tubercle, pubic crest, pubic symphisis, inferior and superior pubic rami, oburator foramen
39
where does the inguinal ligament run from and to?
ASIS to pubic tubercle
40
what does the inguinal ligament form?
floor of inguinal ligament
41
what is the lacunar ligament formed from?
lateral reflection of inguinal ligament from pubic tubercle to pectineal line
42
Where is the superficial ring located?
Supralateral to pubic tubercle
43
What thickens the lateral edges of the SIR?
Medial and lateral crura
44
Where is the deep inguinal ring?
Halfway down the inguinal ligament
45
What makes up the 4 walls of the inguinal ring?
Anterior – External oblique, Inferior – inguinal ligament, posterior – Transversalis fascia, superior – Internal oblique and Transversus abdominis.
46
What makes up the conjoint tendon and where is it found?
Made up of fused fibres of IO and TA. Lies directly posterior to the superficial inguinal ring
47
What is the epiploic foramen and what forms its 4 walls?
Gap between the greater and lesser sacs. Superior – liver, inferior – duodenum, anterior – lesser omentum, posterior – inferior vena cava
48
How many layers of peritoneum does the greater omentum have above the Transverse colon?
6
49
How many layers of peritoneum does the greater omentum have below the Transverse colon?
4
50
Which two ligaments form the lesser omentum?
Hepatoduodenal and hepatogastric
51
What does the free edge of the lesser omentum carry?
The portal triad – portal vein, hepatic artery, bile duct
52
What are the 9 retroperitoneal organs?
Suprarenal gland, aorta, duodenum, pancreas, ureter, colon (ascending and descending), kidneys, Oesophagus, rectum
53
Which hepatic ligament does the lesser sac form?
Posterior coronary ligament
54
Which hepatic ligament does the greater sac form?
Anterior coronary ligament
55
What lies between the Posterior and anterior coronary ligaments?
Bare area of the liver
56
At what spinal level does the oesophagus pierce the diaphragm?
T10
57
List the parts of the stomach.
Cardia, fundus, body, pylorus (pyloric antrum, pyloric canal, pyloric sphincter)
58
What attaches to the greater curvature of the stomach?
Greater omentum
59
What attaches to the lesser curvature of the stomach?
Lesser omentum
60
What are the 4 parts of the duodenum?
Superior, descending, horizontal, ascending
61
Which landmark splits the foregut from the midgut?
Major papilla
62
What is the function of the papillae in the duodenum?
Allow bile and pancreatic juice to pass into the intestine
63
What are the jejunum and ileum suspended by?
The mesentery
64
Where does the jejunum start?
At the duodenojejunal flexure
65
In which direction does the small intestine run?
UL quadrant to LR quadrant
66
What is the demarcation between ileum and jejunum?
There isn’t one
67
What are the differences between ileum and jejunum?
Jejunum redder, greater calibre, thicker walls
68
What are plique circulares?
Amplifications in the intestinal wall that increase the SA
69
What 3 features of the large intestine differentiate it from small intestine?
Taeniae coli, Appendices epiploicae, haustra
70
What are taeiniae coli?
3 longitudinal bands of muscle that originate from the appendix.
71
What are Appendices epiploicae?
Fatty tags on the outside of the large intestine
72
Where does the ileum join the large intestine?
At the ileocaecal junction
73
What is the caecum?
First part of the large intestine that is a blind ended pouch
74
What attaches to the caecum?
Appendix
75
Describe the path of the large intestine from the caecum.
Runs superiorly as the ascending colon, turns left at hepatic flexure and runs as Transverse colon to the splenic flexure as it turns downwards and runs inferiorly as descending colon to the sigmoid colon which then leads into the rectum
76
Where does midgut turn to hindgut?
2/3 way down transverse colon
77
At what spinal level is the duodenojejunal junction?
L2
78
Which ligament supports the duodenojejunal junction?
Ligament of treitz
79
Where is the fissure of the liver?
Sagittal fissure on the anterior diaphragmatic surface
80
What are the 5 parts of the pancreas?
Head, neck, body, tail, uncinate process
81
Where does the head of the pancreas lie?
In the concavity of the duodenum
82
Where does the pancreas run to?
The spleen
83
Where does the root of the mesentery run from and to?
Duodenojejunal junction to ileocaecal junction
84
What is the mesentery supplied by?
Superior mesenteric artery
85
Where does the root of the transverse mesocolon run?
Along anterior side of the pancreas
86
What are the 3 peritoneal ligaments of the greater sac?
Gastrosplenic, gastrophrenic, gastrocolic (greater omentum – from greater curvature of the stomach to the PAW)
87
Which two ligaments suspend the spleen?
Gastrosplenic and splenorenal (attaches spleen to PAW)
88
If the spleen enlarges in which direction does it expand and why?
From UL to LR – due to phrenicolic ligament attaching splenic flexure to the diaphragm
89
What is the lesser omentum a remnant of?
The ventral mesentery
90
What developed within the ventral mesentery?
Liver
91
What is the falciform ligament?
Remnant of ventral mesentery that attches the liver to the AAW
92
What does the thickened edge of the falciform ligament carry?
Ligamentum Terries – fibrosed umbilical vein.
93
What to the triangular ligaments form from?
The thickened edges of the anterior and posterior coronary ligaments
94
Where do the paracolic gutter run?
Lateral to the ascending and descending colons
95
What do the paracolic gutters allow?
Free fluid to pass around the abdomen
96
What does the coeliac trunk supply?
The foregut – liver, gall bladder, stomach, duodenum, spleen, pancreas
97
What does the coeliac trunk come off and at which spinal level?
abdominal aorta – comes off at the aortic hiatus at the lower border of T12.
98
What are the three branches of the coeliac trunk?
Left gastric, splenic artery, common hepatic artery
99
Describe the path of the left gastric artery.
Ascends to oesophagus where it gives off an oesophageal branch. Curves down and round the lesser curvature of the stomach where it will anastomose with the right gastric artery
100
Describe the path of the splenic artery.
It is the largest branch of the coeliac trunk. Passes posterior to the stomach along the superior border of the pancreas passing towards the hilum of the spleen. Gives off short gastric arteries that supply the fundus. Also gives branch that runs along the greater curvature of the stomach –left gastro-omental artery.
101
What does the common hepatic artery bifurcate into?
Gastroduodenal artery and hepatic artery proper
102
Describe the path of the hepatic artery proper.
Gives off right gastric artery which anastomoses with left on lesser curvature. Then branches to left and right hepatic artery which supply the 2 main lobes of the liver.
103
What comes off the right hepatic artery and what does it supply?
Cystic artery supplying the gall bladder
104
Describe the path of the gastroduodenal artery.
Passes to duodenum where it gives off supraduodenal branch. Continues posterior to duodenum where it branches into right gastro-omental artery and superior pancreaticoduodenal artery. The right gastro-omental anastomoses with the left and superior pancreaticoduodenal splits into anterior and posterior branches the supply the duodenum and head, neck and uncinate process of the pancreas
105
At which spinal level does the superior mesenteric artery come away from the abdominal aorta?
Upper border L1
106
What does the superior mesenteric artery branch into?
Middle, right and ileocolic arteries, inferior pancreaticoduodenal artery and numerous jejunal and ileal branches.
107
What does the inferior pancreaticoduodenal artery supply?
The posterior and anterior sides of the head, neck and uncinate process of the pancreas and the inferior sections of the duodenum
108
What does the middle colic artery supply?
Transverse colon
109
What does the right colic artery supply?
Ascending colon
110
What does the ileocolic artery supply?
Caecum and branches to give off appendicular artery which runs posterior to the ileum to supply the appendix
111
What is the marginal artery?
A channel that runs along the edge of the colon that the arteries feed into and gives off short arteries to supply the colon
112
What do the jejunal and ileal branches of the superior mesenteric artery form?
Arterial arcades
113
How do arterial arcades supply blood?
Form a channel running parallel to the small intestine. Give off short vasa recta that supply blood to the intestines
114
At which spinal level does the inferior mesenteric artery branch off the abdominal aorta?
L3
115
What branches off of the inferior mesenteric artery?
Left coli, sigmoidal arteries and superior rectal artery
116
What does the left colic artery split into?
Ascending and descending left colic
117
How does the left colic run?
Retroperitoneally
118
What are the 4 lobes of the liver?
Left, right, caudate, quadrate
119
How many functional segments does the liver have?
8
120
What is the function of the spleen?
Produce both RBCs and WBCs, act as a reservoir of blood.
121
What are caput medusae and why do they form?
Recanulation of umbilical veins due to portal hypertension
122
What are the left and right lobes of the liver separated by?
Falciform ligament
123
What is the ligament terres?
Thickening of the free edge of the falciform ligament
124
Where is the caudate lobe of the liver found?
Visceral surface between the IVC and left lobe
125
Where is the quadrate lobe of the liver found?
Visceral surface between the gall bladder and left lobe, inferior to caudate lobe
126
What is the porta hepatis and where is it found?
Portal triad when in the liver found on the visceral surface.
127
What joins to form the common hepatic duct?
Left and right hepatic duct
128
What joins to form the bile duct?
Cystic duct and common hepatic duct
129
Which two veins join to form the hepatic portal vein?
Superior mesenteric vein and splenic vein
130
Where does the hepatic portal vein run?
Behind the neck of the pancreas into the free edge of lesser omentum as part of portal triad
131
Where does the superior mesenteric vein always run?
To the right of the SM artery
132
Where does the superior mesenteric vein collect blood from?
The midgut
133
Which veins join to form the inferior mesenteric vein?
Superior rectal veins, sigmoidal veins, left colic veins
134
Where does the inferior mesenteric vein run?
Runs into the splenic vein
135
What happens to the hepatic portal vein when it reaches the liver?
Splits into left and right portal veins
136
Where does the venous blood from the liver drain into?
The IVC through left, right and middle hepatic veins
137
What can liver disease lead to?
Portal hypertension
138
How does the body combat portal hypertension?
Redirects blood into systemic systems
139
Which systemic systems can the portal vein lead into?
Azygous system, paraumbilical veins, middle and inferior rectal veins, retroperitoneal veins
140
Where can the azygous system receive portal blood from?
Oesophageal and gastric veins
141
If paraumbilical veins are used to return blood back to IVC what can this cause?
Caput medusae
142
Where would the middle and inferior rectal veins lead?
Anastomose with the superior rectal vein which drain into the internal iliac vein
143
Where does the bile duct run and what does it unite with to form?
Runs behind head of pancreas and unites with the pancreatic duct to form the hepatopancreatic ampulla
144
Where is the hepatopancreatic ampulla?
On the medial surface of the descending duodenum
145
What surrounds the hepatopancreatic ampulla?
Hepatopancreatic sphincter (sphincter of oddi)
146
Is the pancreas intra or retroperitoneal?
Mainly Retro, tail intra
147
Describe the situation of the pancreas.
Head in concavity of duodenum, extends left towards the spleen and the tail becomes intraperitoneal when it reaches the hilum of the spleen. The uncinated process runs along the transverse duodenum
148
Describe the situation of the spleen.
Sits against ribs 9, 10, 11 on the left hand side
149
Where does the gall bladder sit?
Visceral surface of the liver
150
What is the hepatopancreatic sphincter controlled by?
The ANS – PS relaxes sphincter to aid digestion
151
Where does the minor pancreatic duct run to?
The minor papilla
152
Which arteries coming from the splenic artery supply the pancreas?
Dorsal and greater pancreatic artery
153
Which part of the pancreas does the dorsal pancreatic artery supply?
Body
154
Which part of the pancreas does the greater pancreatic artery supply?
Tail
155
What does the common hepatic artery bifurcate into?
Hepatic artery proper and gastroduodenal artery
156
What is the first branch off of the superior mesenteric artery?
Inferior pancreaticoduodenal artery
157
Where does the superior mesenteric artery lie?
Anterior to horizontal duodenum and the uncinated process of the pancreas
158
What is a gastric ulcer?
Damage to the mucosal membrane of the stomach
159
What are the most common causes of gastric ulcers?
Increased acid production, wearing away of lining, pylori bacteria, use of NSAIDs
160
Where do gastric ulcers usually occur?
Lesser curvature
161
How can you tell the difference between a gastric and duodenal ulcer?
Length of time for pain to occur after eating. Gastric – 1-2 hrs, duodenal – 3-4 hrs
162
What can the complications of gastric ulcers be?
Perforation leading to peritonitis, haemorrhage leading to vomiting blood and black tarry stools, obstruction leading to projectile vomiting
163
How are ulcers treated?
Antacids
164
What causes gall stones?
Crystallization of bile salts – often associated with high cholesterol and red blood cell breakdown
165
What are the symptoms of gall stones?
Abdominal pain, high temperature, jaundice, pale stool, dark urine, diarrhoea
166
How do you treat gallstones?
Cholecystectomy
167
What are the symptoms of colon cancer?
Blood in stool, abdominal pain, weight loss, unusual bowel movements
168
How is colon cancer diagnosed?
Rectal exam, colonoscopy
