Anatomy overview II

Question 1

How long is the oesophagus?

Answer 1

25cm?

Question 2

What are the 3 constrictions of the oesophagus?

Answer 2

o	Cervical (pharyngo- esophageal): – 15cm from incisor teeth (IT)
o	Thoracic (broncho – aortic): – crossed by arch of aorta (22.5 fromIT) and left main bronchus 27.5cm from IT)
o	Diaphragmatic: Where it passes through the oesophageal hiatus of the diaphragm- 40 cm from IT

Question 3

How far from the incisor teeth is the cervical constriction of the oesophagus?

Answer 3

15cm

Question 4

How far from the incisor teeth is the thoracic constriction of the oesophagus?

Answer 4

27.5cm

Question 5

How far from the incisor teeth is the diaphragmatic constriction of the oesophagus?

Answer 5

40cm

Question 6

What makes up the stomach bed?

Answer 6

Diaphragm, spleen, left kidney, adrenal gland, splenic artery, pancreas, transverse mesocolon and colon

Question 7

Describe a vagotomy

Answer 7

Vagotomy is a surgical procedure that removes part of the vagus nerve that innervates the lower oesophagus and stomach, and therefore reduces the production of acid in stomach. This leaves the nerve of Laterjet in place to ensure the emptying function of the stomach remains intact.

Question 8

What does the lesser omentum enclose?

Answer 8

The lesser omentum, enclosing the portal triad (portal vein, hepatic artery and bile duct), passes from the liver to the lesser curvature of the stomach and the first 2cm of the superior part of the duodenum

Question 9

How many lobes does the liver have?

Answer 9

Right
Left
Caudate
Quadrate

Question 10

What is the right sagittal fissure?

Answer 10

The right sagittal fissure is the continuous groove formed by the fossa for the gallbladder anteriorly and the groove for the IVC posteriorly

Question 11

What is the left sagittal fissure?

Answer 11

The left sagittal fissure is the continuous groove formed anteriorly by the fissure for the round ligament and posteriorly by the fissure for the ligamentum venosum

Question 12

What embryological feature becomes the round ligament of the liver?

Answer 12

The round ligament of the liver (L. ligamentum teres) is the remains of the umbilical vein

Question 13

What embryological feature becomes the ligamentum venosum?

Answer 13

The ligamentum venosum is the fibrous remains of the foetal ductus venosus, which shunted blood from the umbilical vein to the IVC

Question 14

How much bile can be stored in the gallbladder?

Answer 14

50ml

Question 15

What artery supplies the gallbladder and where is it found?

Answer 15

Cystic artery

Lies in the triangle of calot (triangle between common hepatic duct, cystic duct and visceral surface of the liver)

Question 16

Describe exocrine production by the pancreas

Answer 16

pancreatic juice

Question 17

Describe endocrine production by the pancreas

Answer 17

insulin and glucagon

Question 18

Where is the pancreas?

Answer 18

Lies along the transpyloric plane (L1/L2)

Question 19

Where is the portal vein formed?

Answer 19

Behind the neck of the pancreas (L2)

Question 20

Where is the spleen found?

Answer 20

• Located in the left hypochondrium
• Entirely covered by peritoneum except at the hilum
• Related to 9 to 11 ribs on the left side

Question 21

What is the blood supply of the foregut?

Answer 21

Celiac trunk
Origin: Abdominal aorta (T12)
Main branches:
o Left gastric artery – runs along the lesser curvature of the stomach
o Hepatic artery – supply liver and gallbladder
o Splenic artery – Runs retroperitoneally along the superior (upper) margin of the pancreas

Question 22

Where does the celiac trunk branch off the aorta?

Answer 22

T12

Question 23

List some midgut structures

Answer 23

• Small intestine including most of duodenum

* The cecum, appendix, ascending colon, and the right half to two-thirds of the transverse colon

Question 24

Which part of the duodenum receives bile and pancreatic secretions?

Answer 24

It’s second part receives bile and pancreatic duct secretions

Question 25

What is the blood supply of the midgut?

Answer 25

Superior mesenteric artery

Question 26

Where does the superior mesenteric artery branch off the aorta?

Answer 26

L1

Question 27

List the branches of the superior mesenteric artery

Answer 27

Main branches: Jejunal and ileal arteries | Other branches: Middle colic, right colic and iliocoloic

Question 28

List some hindgut structures

Answer 28

Left one-third of transverse colon, descending colon, sigmoid colon, rectum and upper part of anal canal Epithelium of the urinary bladder and most of the urethra

Question 29

Describe the blood supply of the hind gut

Answer 29

Inferior mesenteric artery

Question 30

Where does the inferior mesenteric artery branch off the aorta?

Answer 30

L3

Question 31

How can you distinguish the large intestine from the small intestine?

Answer 31

Omental appedices – small, fatty, peritoneal like projections (yellow) of colon Haustra or sacculations – pouches of the colon between the teniae Teniae coli – Three thickened bands of smooth muscle (longitudinal layer)

Question 32

Whats the most common position of the appendix?

Answer 32

Retrocecal

Question 33

List the 3 branches of the inferior mesenteric artery

Answer 33

Left colic, sigmoid arteries and superior rectal artery

Question 34

What is the terminal branch of the inferior mesenteric artery?

Answer 34

Superior rectal artery

Question 35

At what level is the recto-sigmoid junction?

Answer 35

S3

Question 36

What structures can be palpated in rectal examinations?

Answer 36

``` Structures palpated through rectum are: o 1) Male: Prostate and Seminal gland o 2) Female – Cervix In both the sexes: o Ischial spines & tuberosities o Enlarged internal iliac lymph nodes o Sacrum and coccyx o Collections in rectovesical (male) and rectouterine fossa (female) ```

Question 37

Describe the parasympathetic innervation of the abdomen

Answer 37

o Vagus nerve (10th cranial nerve) | o Pelvic splanchnic nerves (S2,S3 & S4)

Question 38

Describe the sympathetic innervation of the abdomen

Answer 38

o Abdominopelvic splanchnic nerves (greater – T5-T9, lesser-T10-T11 and least –T12) o Preveretebral sympathetic ganglia o Abdominal aortic plexus

Question 39

Describe the formation of the portal vein?

Answer 39

By the union of splenic vein with the superior mesenteric vein

Question 40

List 3 sites of porto-systemic anastomoses and their clinical significance

Answer 40

o Anorectal junction – Haemorrhoids or piles o Gastroesophageal junction - esophageal varices o Around the umbilicus – caput medusae

Question 41

Describe lymphatic drainage of the abdomen

Answer 41

Lumbar nodes include 3 terminal groups o Pre-aortic (celiac, superior and inferior mesenteric nodes) – Drains organs supplied by the anterior branches of aorta o Lateral aortic – Drains organs supplied by lateral aortic branches o Retro-aortic – drains the posterior abdominal wall * Foregut structures – Celiac group * Midgut structures- Superior mesenteric group * Hindgut structures – Inferior mesenteric group