GI Tract Anatomy Flashcards
1
Q
What is the 4 layers of the oesophagus?
A
Mucosa
Submucosa
Muscle
Adventitia
2
Q
What is the epithelium of the oesophagus?
A
Non-keratinised stratified squamous epithelium
3
Q
Where are the 4 physiological lumen constrictions?
A
Arch of aorta
Bronchus
Cricoid cartilage
Diaphragmatic hernia
4
Q
What is the outer covering in the intraperitoneal portion of the oesophagus?
A
Serosa
5
Q
What is the arterial supply of the oesophagus?
A
Left gastric
Left inferior phrenic
6
Q
What is the venous drainage of the oesophagus?
A
Left gastric (portal)
Azygous (systemic)
7
Q
What is the innervation of the oesophagus?
A
Oesophageal plexus
Parasympathetic: vagal trunks
Sympathetic: cervical and thoracic trunks
8
Q
What is the lymphatics of the oesophagus?
A
Superior- deep cervical plexus
Middle- superior and posterior mediastinal nodes
Lower- left gastric and celiac nodes
9
Q
What are the areas of the stomach?
A
Cardia
Fundus
Body
Pylorus: antrum, canal, sphincter
10
Q
What is the greater and lesser omentum?
A
Greater- sheet of visceral peritoneum that hangs down from greater curvature and attaches to the transverse colon
Lesser- sheet of visceral peritoneum that arises at the lesser curvature and attaches to the liver
11
Q
Is the stomach intraperitoneal or retroperitoneal?
A
Intraperitoneal
12
Q
What is the arterial supply of the stomach?
A
Left gastric
Right gastric
Left gastroepiploic
Right gastroepiploic
13
Q
What is the venous drainage of the stomach?
A
Right gastric, left gastric -> hepatic portal
Short gastric, right gastroepiploic, left gastroepiploic -> SMV
14
Q
What is the innervation of the stomach?
A
Parasympathetic- vagal trunk anterior and posterior
Sympathetic- T6-T9 and passes to coeliac plexus via greater splanchnic nerve
15
Q
What is the lymphatics of the stomach?
A
Gastric nodes at lesser curvature
Gastroepiploic nodes at greater curvature
16
Q
What are the vertebral levels of the 4 parts of the duodenum?
A
Superior: L1
Descending: L1-L3
Horizontal: L3
Ascending: L3-L2
17
Q
What is the arterial supply of the duodenum?
A
Proximal to major papilla (forgeut): gastroduodenal artery
Distal to major papilla (midgut): inferior pancreaticoduodenal artery
18
Q
What is the venous drainage of the duodenum?
A
Hepatic portal vein
19
Q
Is the duodenum intraperitoneal or retroperitoneal?
A
The ascending portion is intraperitoneal
The rest is retroperitoneal
20
Q
What are the features of the jejunum?
A
Thick wall
Long vasa recta
Less arcades
Red in colour
21
Q
What are the features of the ileum?
A
Thin wall
Short vasa recta
More arcades
Pink in colour
22
Q
Is the jejunoileum intraperitoneal or retroperitoneal?
A
Intraperitoneal
23
Q
What is the arterial supply of the jejunoileum?
A
Superior mesenteric artery
24
Q
What is the venous drainage of the jejunoileum?
A
SMV -> hepatic portal vein
25
Is the caecum intraperitoneal or retroperitoneal?
Intraperitoneal
26
What is the arterial supply of the caecum?
Ileocolic a. (gives off anterior cecal and posterior colic)
27
What is the venous drainage of the caecum?
Ileocolic vein -> SMV
28
What is the innervation of the caecum?
Superior mesenteric plexus
29
What is the lymphatics of the caecum?
Ileocolic lymph nodes
30
Is the colon intraperitoneal or retroperitoneal?
Ascending- retro
Transverse- intra
Descending- retro
Sigmoid- intra
31
What is the arterial supply of the colon?
Ascending: ileocolic, right colic (SMA)
Transverse: right colic (SMA), middle colic (SMA), left colic (IMA)
Descending: Left colic (IMA)
Sigmoid: sigmoid arteries (IMA)
32
What is the venous drainage of the colon?
Ascending: SMV
Transverse colon: SMV
Descending: IMV
Sigmoid: IMV
33
What is the innervation of the colon?
Midgut: SMP
Hindgut: IMP
34
Where does the rectum begin?
S3
35
How is the rectum distinct from the colon macroscopically?
Absence of:
Teniae coli
Haustra
Omental appendices
36
What are the peritoneal covers of the rectum?
Superior 1/3- Intraperitoneal
Middle 1/3- Retroperitoneal
Lower 1/3- No peritoneum
37
What are the flexures of the rectum?
Sacral
Anorectal
Lateral
38
What is the arterial supply of the rectum?
Superior rectal (Inferior mesenteric)
Middle rectal (Internal iliac)
Inferior rectal (Internal pudendal)
39
What is the venous drainage of the rectum?
Superior rectal drains into portal system
Middle rectal drains into systemic
Inferior rectal drains into systemic
40
What is the innervation of the rectum?
Sympathetic: lumbar splanchnic nerves, Superior/inferior hypogastric plexuses
Parasympathetic: S2-S4 via pelvic splanchnic nerves and inferior hypogastric plexus
41
What is the lymphatics of the rectum?
Pararectal nodes -> inferior mesenteric nodes
Internal iliac nodes
42
What are the anal sphincters?
Internal- formed from thickening of involuntary circular smooth muscle in the bowel wall
External- voluntary muscle
43
How is the mucosa organised in the anal canal?
Longitudinal folds called anal column
44
How is the mucosa organised in the anal canal?
Longitudinal folds called anal colum
45
What is the pectinate (dentate) line?
Line which divides the upper two-thirds and lower third of the anal canal.
46
What are the embryological derivatives above and below the pectinate line?
Above- hindgut
Below- ectoderm of proctodeum
47
What is the arterial supply of the anal canal above the pectinate line?
Superior rectal a. (IMA)
48
What is the venous drainage of the anal canal above the pectinate line?
Superior rectal drains into IMV
49
What is the innervation of the rectum above the pectinate line?
Inferior hypogastric plexus
50
What is the lymphatics of the anal canal above the pectinate line?
Internal iliac nodes
51
What is the arterial supply of the anal canal below the pectinate line?
Inferior rectal a. (internal pudendal)
52
What is the venous drainage of the anal canal below the pectinate line?
Inferior rectal drains into internal pudendal vein (Systemic)
53
What is the innervation of the anal canal below the pectinate line?
Inferior rectal nerves
54
What is the lymphatics of the anal canal below the pectinate line?
Superficial inguinal lymph nodes
55
What are the unpaired branches of the aorta and their vertebral level?
Celiac trunk (T12)
Superior mesenteric (L1)
Inferior mesenteric (L3)
56
What are the branches of the celiac trunk?
Left gastric
Splenic
Common hepatic
57
What are the branches of the left gastric artery?
Oesophageal branches
58
What are the branches of the splenic artery?
Left gastroepiploic
Short gastric
Pancreatic
59
What are the branches of the common hepatic artery
Proper hepatic
- Right gastric
- Left and Right hepatic (cystic)
Gastroduodenal
- Right gastroepiploic
- Superior pancreaticoduodenal
60
What are the branches of the superior mesenteric artery?
Inferior pancreaticoduodenal
Jejunal and Ileal
Middle colic
Right colic
Ileocolic
61
What are the branches of the inferior mesenteric artery?
Left colic
Sigmoid
Superior rectal
62
What are the paired branches of the aorta and their vertebral level?
Inferior phrenic (T12)
Adrenal (L1)
Renal (L2)
Gonadal (L2)
Lumbar (L1-L4)
Common iliac (L5)
63
Where are the portosystemic anastomoses?
- Oesophageal branches + oesophageal tributaries to the azygous system
- Superior rectal + Inferior rectal
- Portal tributaries of mesenteric veins + retroperitoneal veins
- Portal veins of liver + veins of anterior abdominal wall
64
What are the subdivisions of the peritoneal cavity?
Greater sac
Lesser sac
65
What are the subdivisions of the greater sac?
Divided by transverse mesocolon
- Supracolic compartment
- Infracolic compartment
Compartments connect by paracolic gutters
66
What is SADPUCKER?
Retroperitoneal organs
Suprarenal glands
Aorta/IVC
Duodenum (not proximal 2cm)
Pancreas (not tail)
Ureters
Colon (asc. + desc.)
Kidneys
Esophagus
Rectum
67
What is the inguinal canal?
Pathway for structures to pass from abdominal wall to external genitalia
68
How is the deep inguinal ring formed?
Transversalis fascia
69
How is the superficial inguinal ring formed?
Evagination of external oblique
70
What are the contents of the inguinal canal?
Spermatic cord in males
Round ligament in females
Ilioinguinal nerve
Genital branch of genitofemoral nerve
71
What is the roof of the inguinal canal made of?
Transversalis fascia
Internal oblique
Transversus abdominis
72
What is the posterior wall of the inguinal canal made of?
Transversalis fascia
73
What is the anterior wall of the inguinal canal made of?
Aponeurosis of external oblique
Internal oblique
74
What is the floor of the inguinal canal made of?
Inguinal ligament
Lacunar ligament
75
What are the regions of the inguinal triangle?
Medial- lateral border of rectus abdominis
Lateral- inferior epigastric vessels
Inferior- inguinal ligament
76
What is the lumbar plexus formed by?
Anterior rami of T12-L4
77
How many major peripheral nerves are there in the lumbar plexus?
6
78
What are the 6 major nerves of the lumbar plexus and their root values?
Iliohypogastric (T12-L1)
Ilioinguinal (L1)
Genitofemoral (L1-L2)
Lateral cutaneous nerve of thigh (L2-L3)
Obturator (L2-L4)
Femoral (L2-L4)
79
What is the mnemonic to remember the nerve of the lumbar plexus?
I, I Get Leftovers On Fridays
80
What makes up the anterior wall of the rectus sheath?
External oblique
Half of internal oblique
81
What makes up the posterior wall of the rectus sheath?
Half of internal oblique
Transversus abdominis
82
What is the arcuate line of the rectus sheath?
Horizontal line that demarcates the lower limit of the posterior layer of the rectus sheath.
83
What muscles make up the anterolateral abdominal wall?
External oblique
Internal oblique
Transversus abdominis
Rectus abdominis
Pyramidalis
84
What muscles make up the posterior abdominal wall?
Quadratus Lumborum
Psoas major
Psoas minor
Iliacus
Diaphragm
85
What are the lobes of the liver?
Left
Right
Quadrate
Caudate
86
What are the ligaments of the liver?
Left triangular
Right triangular
Coronary ligament
Falciform ligament
Round ligament
87
What is the peritoneal coverings of the liver?
Intraperitoneal
Bare area has no peritoneum. It is attached directly to the diaphragm by loose connective tissue.
88
What is the microscopic structure of the liver?
Hepatocytes arranged into lobules
Each lobule has a central vein
At the periphery of each lobule is a Portal triad
89
What is the arterial supply of the liver?
Hepatic artery proper (25%)
Hepatic portal vein (75%)
90
What is the venous drainage of the liver?
Central veins -> Hepatic veins -> IVC
91
What is the innervation of the liver?
Hepatic plexus- liver parenchyma
Lower intercostal nerves- fibrous covering
92
What is the lymphatics of the liver?
Hepatic lymph nodes (anterior)
Phrenic and posterior mediastinal lymph nodes (posterior)
93
What is the peritoneal covering of the gall bladder?
Intraperitoneal
94
Where does the gall bladder lie?
In a fossa formed between the right and quadrate lobes of the liver
95
What is the storage capacity of the gall bladder?
30-50ml
96
What is Hartmann's pouch?
Mucosal fold in the neck of the gallbladder
Common location for gallstones to become lodged
97
What is the anatomy of the biliary tree?
Right hepatic + Left hepatic -> Common hepatic duct
Common hepatic + Cystic duct -> Common bile duct
Common bile duct + Pancreatic duct -> Hepatopancreatic ampulla of Vater
98
What is the arterial supply of the gallbladder?
Cystic artery
99
What is the venous drainage of the gallbladder?
Cystic veins (neck)
Hepatic sinusoids (fundus and body)
100
What is the innervation of the gallbladder?
Coeliac plexus
Vagus nerve
101
What is the lymphatics of the gallbladder?
Cystic nodes -> Hepatic nodes -> Coeliac nodes
102
What level is the pancreas positioned at?
Transpyloric plane (L1)
103
What is the peritoneal coverings of the pancreas?
Tail is intraperitoneal
Body, neck and head are retroperitoneal
104
What is the arterial supply of the pancreas?
Pancreatic branches of splenic a.
Superior pancreaticoduodenal (head)
Inferior pancreaticoduodenal (head)
105
What is the venous drainage of the pancreas?
Pancreatic veins -> Splenic vein
Superior mesenteric branches of hepatic portal vein (head)
106
What is the lymphatics of the pancreas?
Pancreaticosplenic nodes+ Pyloric nodes
These drain into superior mesenteric + coeliac nodes
107
What is the vertebral level of the kidneys?
T12-L3
108
What is the peritoneal covering of the kidneys?
Retroperitoneal
109
What is the arterial supply of the kidneys?
Renal arteries
110
What is the venous drainage of the kidneys?
Left + right renal veins
111
What is the lymphatics of the kidneys?
Para-aortic lymph nodes at the origin of the renal arteries
112
What is the peritoneal covering of the adrenal glands?
Retroperitoneal
113
What is the arterial supply of the adrenal glands?
Superior adrenal (inferior phrenic a.)
Middle adrenal (AA)
Inferior adrenal (renal)
114
What is the venous drainage of the adrenal glands?
Right adrenal vein-> IVC
Left adrenal vein-> left renal
115
What is the innervation of the adrenal glands?
Coeliac plexus
Greater splanchnic nerves
116
What is the lymphatics of the adrenal glands?
Lumbar nodes
117
What is the peritoneal covering of the spleen?
Intraperitoneal
118
What is the gastrosplenic ligament?
Connects spleen to greater curvature of stomach
119
What is the splenorenal ligament?
Connects spleen hilum to left kidney
120
What is between the gastrosplenic and splenorenal ligaments?
Lesser sac
121
What is the arterial supply of the spleen?
Splenic artery
122
What is the venous drainage of the spleen?
Splenic vein -> Hepatic portal vein
123
What is the innervation of the spleen?
Coeliac plexus
124
What is the lymphatic drainage of the spleen?
Pancreaticosplenic nodes
125
What vertebral level is the transpyloric plane?
L1
126
What vertebral level is the subcostal plane?
L3
127
What vertebral level is the transumbilical plane?
L4
128
What vertebral level is the transtubercular plane?
L5
129
What are the thoracic splanchnic nerves?
Set of sympathetic nerves that contribute to autonomic supply to abdomen and pelvis
All 3 are preganglionic and form synapses are the celiac ganglion
130
Why are the splanchnic nerves called thoracic?
The nerves all pass through the ganglia of the sympathetic trunk
131
What are the 3 sets of paired thoracic splanchnic nerves?
Greater splanchnic nerves
Lesser splanchnic nerves
Least splanchnic nerves
132
What are the spinal root of the greater splanchnic nerves?
T5-T10
133
What is the spinal roots of the lesser splanchnic nerves?
T10-T11
134
What are the spinal roots of the least splanchnic nerves?
T11-T12
135
What is the function of the greater splanchnic nerve?
Sympathetic supply of foregut and adrenal medulla
136
What is the function of the lesser splanchnic nerve?
Sympathetic supply of the midgut
137
What is the function of the least splanchnic nerve?
Sympathetic supply of the kidneys
138
Where does the greater and lesser splanchnic nerves end?
Celiac ganglion
139
Where does the least splanchnic nerve end?
Renal ganglion
140
What is the origin of the lumbar splanchnic nerves?
L1-L2
141
Where do the lumbar splanchnic nerves end?
Inferior mesenteric ganglion
Hypogastric plexus
