Anatomy - Abdomen

Question 1

Boundaries of anterior abdominal wall:

How many layers

Answer 1

Sup: cartilage of 7th-10th ribs and xiphisternum
Inf: inguinal lig and superior margins of pelvic girlde

3 muscultendonous layers containing a total of 4 muscles.

Question 2

From post to ant what are the muscles of abdo wall?

Describe their course

Answer 2

1) Transversus abdominis: extends medial from thoracolumar fascia to linea alba or ribs sup
2) Int. oblique: Extends superiomedially from thoracolumbar fascia and iliac creast to linea alba and 10th-12th ribs
3) Rectus abdominis: extends superiorly from pubic symph and pubic crest to xiphisternum and 5th-7th ribs
4) External obliques: extend inferiomedialy from 5th-12th ribs to linear alba and anterior half of iliac crest

Question 3

Arterial supply to the anterior abdominal wall:

Answer 3

○ Internal thoracic artery → superior epigastric artery
○ Aorta → subcostal artery
○ External iliac artery → inferior epigastric artery
○ Femoral artery → superficial epigastric artery

Question 4

Venous drainage and key clinical anasatamosis of anterior abdominal wall:

Answer 4

○ Superior
■ internal thoracic vein → brachiocephalic vein
■ lateral thoracic vein → axillary vein
○ Inferior
■ superficial epigastric vein → accessory saphenous → great saphenous → femoral vein
■ inferior epigastric vein → external iliac vein
○ Anastomoses
■ between lateral thoracic vein and superficial epigastric vein
● blood from thorax can drain into femoral vein and from lower abdomen can drain to axillary
■ around the umbilicus with para-umbilical veins from the portal system

Question 5

Lymphatic drainage of the anterior abdominal wall can be divided into:

Answer 5

Superficial and deep:
●	Superficial
      ○	Superior
■	axillary lymph nodes
■	parasternal lymph nodes
       ○	Inferior
■	superficial inguinal lymph nodes

● Deep
○ Accompany deep veins of the abdominal wall and drain to
■ external iliac, common iliac, para-aortic nodes

Question 6

The pyloric sphincter is at what verterbral level? It demarcates what?

Answer 6

The pyloric sphincter demarcates the transpyloric plane at the level of L1

Question 7

The pylorus of the stomach can be divided into?

Answer 7

Antrum, canal, sphincter

Question 8

Anatomical relations of the stomach:

Answer 8

Superior:
Oesophagus and left dome of the diaphragm
Anterior:
Diaphragm, greater omentum, anterior abdominal wall, left lobe of liver, gall bladder
Posterior:
Lesser sac, pancreas, left kidney, left adrenal gland, spleen, splenic artery, transverse mesocolon

Question 9

Greater curvature: Arising at the ……. …….., it arches backwards and passes ……… to the …….. It curves to the …… as it continues medially to reach the pyloric antrum.

Answer 9

Greater curvature – forms the long, convex, lateral border of the stomach. Arising at the cardiac notch, it arches backwards and passes inferiorly to the left. It curves to the right as it continues medially to reach the pyloric antrum.

Question 10

Supply to the greater curvature:

The ….. ….. ….. and the ….. and ….. …..-….. arteries supply branches to the greater curvature of the stomach

Answer 10

The short gastric arteries and the right and left gastro-omental arteries supply branches to the greater curvature.

Question 11

At what vertebral level is the coeliac trunk? What are the vessels from Left to right?

Answer 11

It arises from the anterior aspect of the aorta, at the aortic hiatus of the diaphragm (T12 level).
Left to right:
left gastric (eosophageal and left gastric branches), splenic and common hepatic arteries.

The Splenic passes under the left gastric to become the left-most vessel, giving off 2 branches to the greater curvature (left gastroepiploeic and short gastric) and pancreas (pancreatic branches)

Question 12

Branches of the common hepatic artery:

Answer 12

Sole arterial supply to the liver and the only branch of the coeliac artery to pass to the right.
Past the anterior aspect of the duodenum divides into 2 branches:
1) Proper hepatic:
- Right gastric - pylorus and lesser curvature of the stomach
- Right and left hepatic: divide inferior to the porta hepatis
- Cystic
2) Gastroduodenal:
- Right gastroepiploic (terminal branch): large portion of greater curvature of the stomach and greater omentum, which it also supplies. Anastamoses with left gastroepiploeic/omental aa. from splenic
- Superior pancreaticoduodenal: divides into an anterior and posterior branch, which supplies the head of the pancreas.

Question 13

Innervation of the stomach:

Answer 13

1) Parasympathetic: from the anterior and posterior vagal trunks of vagus
2) Sympathetic: Arises from the T6-T9 spinal cord segments and passes to the coeliac plexus via the greater splanchnic nerve. It also carries some pain transmitting fibres.

Question 14

Lymphatic drainage of the stomach

Answer 14

Follows arterial supply to the coeliac nodes.
Greater curvature:
short gastric and left gastro-omental -> Spenic -> trunk
(anastamoses w/),
Right gastro-omental -> gastroduodenal -> common hepatic -> Trunk
Lesser curvature: left gastric (superiorly), Right gastric -> common hepatic ->trunk
Pylorus: Right gastro-omental->gastro duodenal -> hepatic -> Trunk

Question 15

Venous drainage of the stomach:

Answer 15

The veins of the stomach run parallel to the arteries.
Right and left gastric veins drain into the hepatic portal vein.
The short gastric vein, left and right gastro-omental veins ultimately drain into the superior mesenteric vein.

Question 16

Course of the portal vein:

Answer 16

Formed from confluence of splenic v. and SMV posterior to neck on pancreas (L2), proceeds superiorly and rightward behind 1st part of duodenum, joined by left and right gastric veins and pancreo-dudenal vein.

Entrer free margin of lesser omentum anterior to epiploic foramen (traveling with hepatic artery, the portal vein, the common bile duct) to enter liver at portahepaticus where it then divides into left and right.

Question 17

The portal vein accounts for what % of the hepatic blood supply?
How much of the 02 supply?
About how long is it?

Answer 17

75%
50% 02

8cm long

Question 18

Describe the duodenum:

Answer 18

C-shaped hollow viscous, can be divided into 4 parts, parts 2-4 reteroperitoneal. Associated medially w/head/neck pancreas
1st part 1 inch - duodenal cap is above TP plane. connected to the liver by the hepatoduodenal ligament.
2nd Part 2 inches - Descending part from L1-L3, contains papilliary sphincter
3rd Part - Horizontal, across body of L3, IVC and Aorta
4th Part - ascending, up left side of L3-L2

Question 19

Histological layers of the duodenum

Answer 19

● Mucosa
○ lined with columnar epithelium
○ contains lamina propria and muscularis mucosa
● Submucosa containing blood vessels and lymphatics
● Muscularis propria
● Serosa
○ peritoneal on anterior surface

Question 20

How does the mucosal lining differ along the GIT from mouth to anus?

Answer 20

Stratified Squamous Epi: Mouth, eosophagus, anus

Simple Columnar: The rest

Question 21

The duodenum shares its arterial supply with?

Answer 21

The head of pancreas

Question 22

Superior pancreaticoduodenal artery is a branch of? Supplies what?

Inferior pancreaticoduodenal artery is a branch of?
Supplies what?

Answer 22

○ Superior pancreaticoduodenal artery
■ branch of common hepatic artery
■ supplies up to ampulla of Vater

○ Inferior pancreaticoduodenal artery
■ branch of SMA
■ supplies distal to ampulla of Vater

Question 23

Venous drainage of the duodenum (and also)?

Answer 23

Also head of panc:
○ Superior pancreaticoduodenal vein drains to portal vein
○ Inferior pancreaticoduodenal vein drains to SMV

Question 24

Lymphatic drainage of the duodenum?

Answer 24

● Pancreaticoduodenal
● Pyloric
● Superior mesenteric
● Coeliac

Question 25

Compare Jejunum to ileum:

Answer 25

``` Jej: Located in upper left quadrant Thick intestinal wall Longer vasa recta (straight arteries) Less arcades (arterial loops) Red in colour ``` ``` Ileum: Located in lower right quadrant Thin intestinal wall Shorter vasa recta More arcades Pink in colour ```

Question 26

Branches of the common hepatic artery:

Answer 26

From trunk, 1st branch is: 1) Gastroduodenal artery: - Right gastroepiploic - Superior pancreoduodenal 2) Right gastric 3) L and right common hepatic (cystic artery branches off right)

Question 27

General description of the pancreas:

Answer 27

● Lobulated, retroperitoneal organ ● Lies transversely across L1 and L2 vertebra ● Posterior to the stomach and between duodenum (right) and spleen (left) ● Has endocrine and exocrine functions ● Divided into uncinate, head, neck, body and tail.

Question 28

Where lies the head of the pancreas (not specific relations)?

Answer 28

● Right of midline ● Anterior and to the right of the vertebral column ● Within the curve of the duodenum

Question 29

The IVC travels on what side of the abdomen? | What part of the pancreas lies anterior to it?

Answer 29

To the right. | Passes posterior to the head of pancreas

Question 30

Relations of the head of pancreas:

Answer 30

``` ○ Superior: ■ first part of duodenum ○ Inferior ■ 3rd part of duodenum ○ Medial ■ neck of pancreas ○ lateral ■ 2nd part of duodenum ■ superior and inferior pancreaticoduodenal arteries ○ Posterior ■ IVC ■ right renal artery and vein ■ left renal vein ○ Anterior ■ Mesentery and small bowel ```

Question 31

The neck of pancreas is defined as?

Answer 31

Portion that lies anterior to the portal vein

Question 32

Relations of the neck of pancreas?

Answer 32

``` ○ Postero-superior ■ portal vein ■ Splenic vein ○ Antero-superior ■ pylorus ○ Anterior ■ gastroduodenal and anterior superior pancreaticoduodenal arteries ○ Postero-inferior ■ superior mesenteric vein ○ Left ■ body ○ Right ■ head ```

Question 33

What is "special" (anatomically) about the body of the pancreas?

Answer 33

Longest portion of the gland ● 3 surfaces: anterosuperior, posterior, anteroinferior ● Anterior surfaces covered by peritoneum ● Part of pancreas that crosses the midline

Question 34

What passes posterior-inferiorly to the neck of pancreas, but anterior to the uncinate?

Answer 34

Sup mesenteric vessels (i.e SMV joins splenic behind the neck), after passing anteriorly

Question 35

The SMV arises 1cm below? At what vertebral level?

Answer 35

1cm below coeliac trunk, at L1 (a lot of shit happens at L1)

Question 36

Relations of the body of pancreas:

Answer 36

``` ○ Superior ■ Coeliac trunk ● common hepatic artery runs to the right ● Splenic artery runs to the left ○ Inferior ■ Superior mesenteric artery and vein ■ Inferior mesenteric vein ■ 4th part of duodenum ■ duodenojejunal flexure ■ Uncinate is inferior to proximal part ○ Anterior ■ Peritoneum ■ Stomach ○ Posterior ■ L2 vertebra ■ Aorta!!!!!!!! ■ Superior mesenteric artery ■ left adrenal gland ■ left kidney ■ renal vessels ```

Question 37

What is the anatomically exciting feature of the tail of pancreas?

Answer 37

Nothing - get a life. | It is the only part that is intraperitoneal.Though it is inside the splenorenal ligament with the splenic vessels.

Question 38

Relations of the tail of pancreas:

Answer 38

Left: spleen Right: body Post: splenic branches of the splenic artery and splenic vein

Question 39

Microscopic features of the pancreas:

Answer 39

``` ● Exocrine acinar cells ○ secretes protease, lipase and amylase ● Endocrine islets of Langerhans ○ more numerous in the tail ○ alpha type: insulin ○ beta type: glucagon ○ delta type: somatostatin and gastrin ```

Question 40

Superior pancreaticoduodenal artery comes from? | and has what branches

Answer 40

Superior pancreaticoduodenal artery ○ branch of gastroduodenal artery (from common hepatic) ○ anterior and posterior branches

Question 41

Inferior pancreaticoduodenal artery comes from? | and has what branches

Answer 41

Branch of superior mesenteric artery | ○ anterior and posterior branches=

Question 42

Arterial supply of pancreas?

Answer 42

Sup and inf pancreaticoduodenal arteries + Splenic arteries

Question 43

Venous supply of pancreas:

Answer 43

● Head and neck ○ superior and inferior pancreaticoduodenal veins → portal vein or SMV ● Body and tail ○ small veins that drain into splenic vein

Question 44

Lymphatic drainage of pancreas:

Answer 44

``` Follow the arterial supply. Empty into the pancreaticosplenal nodes and the pyloric nodes, which in turn drain into the superior mesenteric and coeliac lymph nodes. ● Head and neck ○ pancreaticoduodenal ○ superior mesenteric ○ hepatic ○ pre-aortic ○ coeliac ● Body and tail ○ pancreaticosplenic nodes ```

Question 45

The unpaired branches of the abdominal aorta and their vertebral levels:

Answer 45

1) Coeliac trunk: Left gastric, splenic, common hepatic @ T12 2) SMA: Inferior pancreoduodenal, middle colic, right colic, jejunal and ileal branches @T1 3) IMA: Left colic, sigmoid arteries. @L3 4) Median sacral artery at L5

Question 46

Arterial supply to large bowel:

Answer 46

Right and middle colic from SMA | Left colic from IMA.

Question 47

The paired branches of the abdominal aorta and their vertebral levels: Which are lateral, which posterior?

Answer 47

1) Inferior phrenic (givens of superior adrenals). Exist more posteriorly @T12 2) Middle suprarenal paired lateral, at same level as coeliac trunk. @T12 3) 1st (of four) lumbar artery. At level of SMA, extends posteriorly (each level 1-4 has a pair of lumbar arteries) 4) Renal arteries (the right passes behind the vena cava @ L1 (inferior to SMA) 5) Gonadal arteries. Pass lateral at L2.

Question 48

The duodenum has the same lymphatic drainage as? | What is it?

Answer 48

Same as head and neck of pancreas: | Splenoduodenal nodes -> Superior mesenteric -> pre aortic ->coeliac.

Question 49

Describe the spleen:

Answer 49

``` Intraperitoneal organ (except at hilum). Of variable size and shape. The Spleen is typically a ovoid or "clenched fist" shaped organ with a long axis around 11cm and a hilum directed medially. Covered by a distensible capsule, connected to the kidney (splenorenal lig), and stomach greater curvature (gastrosplenic lig). Surface can be divided into diaphragmatic surfaces. Diaphragmatic = in contact with diaphragm and inferior ribs 9-11. Parietal surface = Stomach anterior, scenic flexure inferiorly, diaphragm posteriorly, pancreases and left kidney medially. Function: mainly to remove damaged red blood cells. It also plays a role in both cell-mediated and humoral immune responses. ```

Question 50

Anatomic relations of the spleen:

Answer 50

Diaphragmatic Surface (superior) = in contact with diaphragm Parietal surface = Stomach anterior, scenic flexure inferiorly, diaphragm posteriorly, pancreases and left kidney medially.

Question 51

Describe the arterial supply of the spleen:

Answer 51

The splenic artery is the middle branch of the coeliac trunk, it travels laterally to the left in close association with the pancreas which is anterior and inferior, for which it gives off pancreatic branches to the body and tail (dorsal, greater, transverse). Travelling in the splenorenal lig, at the hilum the artery breaks into 5 branches – giving rise to vascular segments of the spleen.

Question 52

Describe the venous supply of the spleen:

Answer 52

Venous drainage = splenic vein = joins superior mesenteric vein to form portal vein behind head of pancreas.

Question 53

Lymphatic drainage of the spleen:

Answer 53

Emerge from the hilum and the splenic nodes Drain into nodes along splenic artery (pancreaticosplenic nodes) and then into coeliac nodes (via potentially SMA, pure aortic and hepatic nodes).

Question 54

Functional cells of the pancreas:

Answer 54

Exocrine gland: secretes enzymes capable of digesting fats, proteins and carbohydrates Endocrine gland: secreting hormones, insulin and glucagon, which are involved in carbohydrate metabolism. Islets of Langerhans which are interspersed throughout the pancreas

Question 55

Histological layers of the stomach

Answer 55

Typical: serosa, muscularis externa, submucosa and mucosa. Mucosa begins at GOJ with increasing folds (Rugae) columna epithelium forming increasingly deeper gastric pits and glands. The later containing mucous secreting (G cells) and H secreting parietal cells, in pylorus D cells secrete somatostatin

Question 56

Pancreas nerve supply?

Answer 56

Sympathetic and parasympathetic via the coeliac plexus

Question 57

General description of the IVC:

Answer 57

``` IVC is the largest vein in the body. • It has no valves • Located post abdominal wall • To the right of the aorta • 20cm long ```

Question 58

How long is the IVC? | Why so short?

Answer 58

``` 20cm starts lower and ends higher + concavity of the thoracic diaphragm ```

Question 59

The IVC leaves the abode cavity at what level? Through what? The enters?

Answer 59

Passes through the canal foramen in the | diaphragm at T8 level, enters the right atrium of the heart

Question 60

Basic rule for levels of IVC tributaries:

Answer 60

``` Correspond to the abdominal aorta except: 1) left testicular/ovarian vein and the left adrenal vein usually drain into the left renal vein (ie. to avoid travelling so far) ```

Question 61

What connects the systems of superior vena cava and inferior vena cava? Describes it course:

Answer 61

The azygos vein. Formed from union of ascending lumbar veins and right subcostal veins at T12, ascending in the posterior mediastinum, and arching over the right main bronchus posteriorly at the root of the right lung to join the superior vena cava. Major tributary is the semi-azygous on the LEFT side.

Question 62

Some general facts about the kidneys (position ect) Lazy card

Answer 62

``` • paired bilateral abdominal organs • located retroperitoneally on the posterior abdominal wall • one on each side of the vertebral column • level of T12 to L3 vertebrae • right kidney lies slightly more inferiorly than the left due to the presence of the right lobe of the liver • the kidneys are suspended from the diaphragm and move with it up to 2.5 cm with respiration ```

Question 63

Relate the laterality of the ureters to the vertebral column:

Answer 63

Just medial to tips of transverse process

Question 64

Colour, size, shape of the kidenys

Answer 64

Redish brown Approx 10 cm in length, 5 cm in width and 4.5 cm in depth Shape: ovoid in shape, with an indentation at the medial border, causing a medial concavity = renal hilum • renal artery and vein, the renal pelvis and nerves and lymphatics enter and leave the kidney

Question 65

From ant to post, what are the structures running into the renal hilum? At what vertebral level

Answer 65

Vein, artery, pelvis Hilum at L1 on Left @ L2 on Right

Question 66

The tissue running between the renal pyramids is called what? The region it is in? The region it leads to? What do the pyramids drain to?

Answer 66

Renal column in renal medulla, join renal cortex. | Pyramids drain to minor calyx

Question 67

The kidneys are surrounded by peri-renal fat and what? | Attachments of this are?

Answer 67

Gerota's (renal) fascia. Attaches to the diaphragmatic fasica superiorly, foins transversus fascia laterally Blends with vessel fascia medially

Question 68

Relations of the LEFT kidney?

Answer 68

Superior: LEFT Supra renal glands, perirenal fat (can put that everywhere along with Groata's), Diaphragm Anterior: - Anteriosuperior: stomach (greater curvature) - Middle: Pancreas and splenic aa/vv - inferior splenic flexure of colon Lateral: Spleen Medial: Pancreas Posterior: Diaphragm, LEFT ribs 11-12, LEFT Psoas maj, LEFT quadratus, LEFT origin of transversus abdominis.

Question 69

Relations of the RIGHT kidney?

Answer 69

Sup: R.Suprarenal gland (fat and fascia) Anterior: - Ant sup = right lobe of liver - Ant inf: Hepatic flexure Post: Right Diaphragm (superior half), and right rib (11,12) Right psoas maj, quadratus lumborum, Right origin of transversus abdominus. Medial: duodenum, renal artery/vein, ureter.

Question 70

The renal artery: Arises from? Passes ? to enter the renal hilum in what relation to the other structures entering/leaving. Which one is longer? Why Each renal artery usually divides into ? segmental arteries before entering the hilum of the kidney

Answer 70

Arises from the aorta at the level of L2 passes laterally to enter the renal hilum posterior to the vein and anterior to the pelvis Which one is longer? Why The right renal artery is longer than the left and passes posterior to the IVC Each renal artery usually divides into five segmental arteries before entering the hilum of the kidney

Question 71

Kidneys can be divided in X segments based on what?

Answer 71

5 segments based on arterial supply.

Question 72

The renal vein: Emerges from the hilum ? to the artery. It drains directly into the? Which is longer? why It passes ? to the aorta, passing ? to the origin of the superior mesenteric artery.

Answer 72

Emerges from the hilum anterior to the artery. It drains directly into the IVC. The left renal vein is longer than the right. It passes anterior to the aorta, passing inferior to the origin of the superior mesenteric artery (remember nut cracker syndrome).

Question 73

Lymphatic drainage of the kidneys

Answer 73

Follows veins: Superficial lymphatic vessels form a plexus under the renal capsule = subcapsular lymphatic plexus. They, along with medullary lymph vessels, communicate with cortical lymph vessels that travel alongside interlobular, arcuate and interlobar arteries. The renal lymphatics then drain directly to the lumbar lymph trunks (which then drain to the thoracic duct and cisterna chyli) and to para-aortic nodes

Question 74

Nerve supply to kidneys:

Answer 74

arise from the renal plexus consists of sympathetic and parasympathetic fibres ``` This plexus is supplied by the splanchnic nerves (abdominopelvic) ```

Question 75

What do the adrenal glands secrete?

Answer 75

``` Cortex (sweeter as you go in) 1) Corticoids from out to in = mineralocorticoids (i.e the salt regulating one i.e aldosterone), glucocorticoids (e.g. cortisone), and 2) Androgens. DHEA and testosterone Medulla: Catecholamines ```

Question 76

Anatomical relations of RIGHT adrenal gland:

Answer 76

Anterior: Perinephric fat, and groat's fascia (same as posterior) then Liver. Anterior medial: IVC - gland extends medially to lie behind IVC Posterior: Right crus of the diaphragm Could extend this further by naming relations of kidney e.g Right origin of transversus is posterior ect.

Question 77

Anatomical relations of LEFT adrenal gland:

Answer 77

Anterior: Spleen, pancreas stomach Posterior: Rests on RIGHT diaphragm

Question 78

Arterial supply to adrenals:

Answer 78

Superior adrenal artery – arises from the inferior phrenic artery Middle adrenal artery – arises from the abdominal aorta. Inferior adrenal artery – arises from the renal arteries.

Question 79

Venous supply to adrenals:

Answer 79

Right and left adrenal veins drain the glands. The right adrenal vein drains into the inferior vena cava, whereas the left adrenal vein drains into the left renal vein.

Question 80

Nerve supply to adrenals - what is particularly important?

Answer 80

Sympathetic innervation to the adrenal medulla is via myelinated pre-synaptic fibres, mainly from the T10 to L1 spinal cord segments. The adrenal glands are innervated by the coeliac plexus and greater splanchnic nerves.

Question 81

Lymphatic drainage of adrenals:

Answer 81

Capsular and Medullary plexi drain to lumbar paraaortic lymph nodes. Lymph drainage is to the lumbar lymph nodes by adrenal lymphatic vessels. These vessels originate from two lymphatic plexuses – one deep to the capsule, and the other in the medulla.

Question 82

How long are the ureters?

Answer 82

25-30cm

Question 83

Describe the course of the ureters:

Answer 83

From ureteropelvic junction at L2, descend through the retroperitoneal abdomen, along the anterior surface of the psoas major. At the sacroiliac joints, they cross the pelvic brim, to enter pelvic cavity. Here they also cross the bifurcation of the common iliac arteries. Within the pelvic cavity, travel inferiorly along pelvic side wall. At the level of the ischial spines, they turn anteromedially, moving in a transverse plane towards the bladder. Piercing its lateral aspect in an oblique manner. This creates a one way valve, where high intramural pressure collapses the ureters.

Question 84

Arterial supply to ureters:

Answer 84

Divide into 3 parts: Upper = renal artery Middle = testicular/ovarian Pelvic = superior vesical artery

Question 85

Venous supply to ureters:

Answer 85

Same as arterial Upper = renal vein Middle = testicular/ovarian Pelvic = superior vesical vein

Question 86

Lymphatic drainage of ureters:

Answer 86

Not the same as blood supply: Upper = follows renal vessels to lumbar aortic nodes Middle = Common iliac nodes Inferior = Common, Internal and external iliac nodes!!

Question 87

What doesn't rain to the thoracic duct (aka)

Answer 87

Aka the left thoracic duct. Drains 75% of the body by not: 1) Head and neck 2) Right thorax 3) Right forequarter,

Question 88

Abdominal course of the thoracic duct

Answer 88

Formed by the confluence of the right and left lumbar trunks, AND Intestinal trunk at T12. This confluence is the cysterna chyli. The Duct enters the thorax via the aortic opening. It ascend posterior to the aorta and anterior to the vertebral bodies.

Question 89

General description of the liver:

Answer 89

Largest gland in the body, and largest visceral organ in the abdocavity, conical shaped with apex directed to he left, weighing around 1.5Kgs. Predominantly located in the right hypochondrium and epigastric areas, and extends into the left hypochondrium. The gallbladder extends Dark reddish brown, encapsulated organ, broadly attached to the right diaphragm it moves 4-8cm with respiration. Divided into 2 major lobes (Left and Right, the left being much larger) by the falciform ligament that extends anteriorly . Numerous functions e.g: glycogen storage and clotting factor production synthesis of bile

Question 90

The liver can be divided into what surfaces?

Answer 90

How do they differ? Diaphragmatic; smooth and dome shapes, In contact with diaphragm anteriorly and superiorly. Attaches broadly to diaphragm over the bare area Visceral surface is postero-inferior: Irregular and molded by adjacent viscera

Question 91

The viceral surface of the liver is moulded by what viscera

Answer 91

``` Oesophagus (need to remember as hard to guess) Stomach Duodenum Hepatic flexure Right Kidney/adrenal Gallbladder ```

Question 92

From right to left, name the liver ligaments above the anterosuperior surface of the liver:

Answer 92

Right Triangular Right coronary Falciform ligament Left coronary

Question 93

The bare area of the liver is enclosed by?

Answer 93

The coronary ligaments

Question 94

Between the anterosuperior surface of the liver and the anterior abdominal wall, ribs and diaphragm lies the? Other spaces are?

Answer 94

Subphrenic recess which extends over the liver until the bare area. Subheaptic and heaptorenal space.

Question 95

What "functionally" makes the left lobe of the liver the same size as the right? Give anatomical detail on the relations.

Answer 95

Caudate and quadrate lobe, though on the right side of the falciform leg are functionally part of the last lobe. The quadrate lobe is inferior, containing the billiard indetatiom. The caudate is caudal (superior)

Question 96

Each lobe of the liver is supplied by:

Answer 96

* hepatic artery, * portal vein * hepatic duct Very little overlap between two sides

Question 97

The liver an be divided in to how many segments? Based on what? How would you guesstimate where each is:

Answer 97

VIII Segments Subunits defined by the principle divisions of the hepatic artery and vein. I is the caudate Either skip to the next question and use the time gained to get more marks there, or: From anterior view, go clockwise from top of L.lobe I sup, II inf III diving the lobes adjacent the falciform. Cont clockwise on the right hoping for the best.

Question 98

What runs in the free edge of the lesser omentum and where does this edge go?

Answer 98

The right and left hepatic artery and portal vein enter the liver, and the right and left hepatic ducts exit the liver. The free edges attaches to the margins of the ports hepatis.

Question 99

Describe the porta hepatis:

Answer 99

The hilum of the liver. Located on the inferior surface of the liver, between Caudate and quadrate lobes. Margins formed by the superior part of the free edge of lesser omentum. Contains the portal veins, hepatic arteries, hepatic ducts, lymphatics and nerves.

Question 100

Describe the functional subunit of the liver:

Answer 100

Lobules: Hexagonal elongated structure containing a central vein surrounded by hepatocytes, each corner of the hexagon contains a triad of portal vein, hepatic artery and bile duct. Canniculi drain bile toward the bile ducts, while portal and arterial blood drains towards the central vein..

Question 101

Describe the gallbladder

Answer 101

A pair-shaped fibrous sac in the right hypochondrial region, lying within a fossa formed by the quadrate and right liver lobe. 7-10cm long, can hold 50mls of bile. Has body, fundus and neck Joins the 4cm typically "S shaped" cystic duct Function is to store and concentrate bile.

Question 102

Relations of the gall bladder

Answer 102

Superiorly: Inferior surface of right lobe of liver and quadrates lobe. Anterior: Anterior abdominal wall, edge of visceral surface of liver Posterior: Transverse colon. D1 and D2 (posteriormedially)

Question 103

Describe the components of the wall of the gallbag

Answer 103

Peritoneum completely covers the fundus, • holds the body and neck firmly against the visceral surface of the liver. (along with connective tissue) Smooth muscle • contracts when cholecystokinin is secreted by the duodenum in response to the presence of fat in the gastrointestinal tract Mucous Membrane • folded and honeycombed, • designed to absorb water from bile to concentrate it

Question 104

Blood supply to the gallbag

Answer 104

Cystic artery and vein Vein drains in right PV Artery is branch of right hepatic

Question 105

Gall bladder lymphatics:

Answer 105

Channels drain towards the neck, then to cystic nodes (at neck) which drain to hepatic nodes at the porta, hepatic nodes follow common heaptic to coeliac nodes.

Question 106

Innervation of the G.Bag

Answer 106

From coeliac trunk (always guess this for upper abdo organs). But also some somatic fibers from right phrenic (shoulder tip pain). Parasympathetics by vagus nerve. Though this action is laregly done by circulating CCK released by the duodenum.

Question 107

How long is the cystic duct?

Answer 107

4cm, S-shaped, contains spiral valve

Question 108

How does the ampula vater terminate

Answer 108

Empties into D2 via the sphincter of oddi and the major duodenal papilla

Question 109

What opens the sphincter of Oddi?

Answer 109

CCK release from duodenum

Question 110

The jejunum begins at the?

Answer 110

The jejunum begins at the duodenojejunal flexure.

Question 111

What is significant about the the blood supply to the duodenum?

Answer 111

``` Proximal part (above papilla) supplied by coeliac trunk. Inferior part by inferior pancreoduodenal artery - a branch of the SMA. – it marks the change from the embryological foregut to midgut. The veins of the duodenum follow the major arteries and drain into the hepatic portal vein. ```

Question 112

Describe the SMA

Answer 112

Arises from the aorta at the level of the L1 vertebrae, immediately inferior to the coeliac trunk. It moves in between layers of mesentery, splitting into approximately 20 branches. These branches anastomose to form loops, called arcades. From the arcades, long and straight arteries arise, called vasa recta.

Question 113

How does the vasa recta differ between jejunum and ileum? Which has a thicker wall

Answer 113

``` Jej= long with fewer arcades Ileum = short ``` Jej does more absorbing so thicker wall (also redder)

Question 114

Describe the rectum

Answer 114

Kind of like Scott Morrison at a Hill-Song event. 13cm hollow viscous pelvic organ connecting the colon to the anus. Closely associated with the sacrum where it begins at S3, it follows this curvature (sacral flexure) as it descends inferiorly in the midline turning posteroinferiorly (pulled by puborectalis) to pierce the pelvic diaphragm to become the anal canal at the level of the coccyx tip. Anteriorly and laterally covered by peritoneum in upper 1/3, only covered anteriorly in middle 1/3rd lower 1/3 has no covering or Serosa. Function: Conduit, water balance, store feces.

Question 115

Relations of the rectum:

Answer 115

Mesorectal fascia circumferentially surrounds rectum as it descends from S3. Superiorly: Rectosigmoid junction and sigmoid colon Inferiorly: anal canal, ANOCOCOCYGEAL LIGAMENT, pirformis muscle. Laterally: sigmoid colon, terminal ileum, ischioanal fossa Anteriorly: - Males: upper 2/3 peritoneum, with rectovesicle pouch and RECTOVESICAL fascia, sigmoid colon and loops of ileum. Inf 1/3 post surface prostate, posterior bladder wall seminal vesicles - Females: Upper 2/3 rectouterine pouch, sigmoid and loops ileum. Lower 1/3 = post FORNIX OF VAG, posterior wall of vagina (I.e dont just say date or vag)

Question 116

Valves of houston:

Answer 116

In the rectum: 1) near the commencement of the rectum, on the right side. 2) extends inward from the left side of the tube, opposite the middle of the sacrum. 3) the largest and most constant, projects backward from the forepart of the rectum, opposite the fundus of the urinary bladder.

Question 117

Arterial supply to rectum:

Answer 117

1) Superior rectal artery (branch of IMA) apupplies proximal rectum and most of the mucosa. 2) Middle rectal artery (branch of internal iliac, sometime inf vesicle artery) mainly supplies muscularis layer 3) Inferior rectal artery (branch of internal pudendal a very inferior branch of the internal iliac) supplies anorectal junction and butt hole.

Question 118

Mesorectal fascia begins where?

Answer 118

S3, where superior rectal artery brifurcates into L and R branches

Question 119

Venous drainage of the rectum:

Answer 119

1) SUBMUCOSAL VENOUS PLEXUS drains to sup middle and inf Superior rectal vein -> IMV ->portal vein ->liver Middle rectal veins -> Internal iliac (i.e systemic) Inf rectal -> Internal pudendal - internal iliac Importantly!!! Anasatomoses between the 3 make portocaval anastomosis.

Question 120

Lymphatic drainage of the rectum:

Answer 120

PARARECTAL NODES - superior and inferior group Superior group: Ascend with superior rectal vessels to drain into INFERIOR MESENTERIC nodes Inferior Group: Follow middle vessels to internal iliac Very inferiorly, can drain to superficial inguinal and external iliac.

Question 121

Innervation of the rectum:

Answer 121

Sympathetic: L1 root to L3 - Lumbar splanchnic -> hypogastric/pelvic plexus -> plexi around inf mesenteric and sup rectal art Parasympathetic: Sacral plexus S2-S4 -> Pelvic plexus Somatic S2-4 - strech info only