The liver has complex anatomy and vasculature. It is divided into 4 lobes and 8 segments based on blood supply. The liver receives dual blood supply from the hepatic artery and portal vein. It has 3 major functions - metabolism, protein synthesis, and bile production. The bile duct drains bile from the liver into the small intestine.

1. Anatomy and Physiology of liver
and billary tract
Worku Awoke –GSR1
Dr .Samuel –Consultant surgeon
jun, 2022
1

2. objective
1 . under stand surface anatomy bounderies of
liver and biiiary tract
2. To under stand functional anatomy of liver and
billary trees
3. To under stand normal ,aberrant and variant
arterial, veous blood supply of liver
4. To know ligaments,spaces and fissures of liver
5. to know lymphatics and innervation of liver
6 .physiologic function of liver and hepatobillare
trees
2

3. Outlines
 Gross Anatomy of liver
Surfaces anatomy and boundries of liver
Segmetnal anatomy of liver
Vasculatures of liver
Normal, aberrant and variant anatomy of liver
vasculature
portalcircuiation
Gallbladder anatomy and phyiology
Physiologic function of liver and billary tract
3

4. Embryology of liver
• The liver primordium, also known as
diverticulum hepatis or liver bud, arises
from endoderm in weeks 3 through 4 of
embryologic development and invades the
septum transversum, vitelline
(omphalomesenteric) veins, and umbilical
veins.
• Its connection to the embryologic
duodenum (foregut) will eventually
become the bile duct.
4

5. 5

6. Gross anatomy of liver
• The liver is the largest organ in the body,
weighing approximately 1500 g
• It is reddish brown and is surrounded by a
fibrous sheath known as Glisson’s capsule
6

7. Surface outline
• Outlines of the liver on
the anterior body wall
– Point A: 1 cm below
right nipple
– Point B: 2 cm below &
medial to left nipple
– Point C: right costal
margin at the anterior
axillary line
7

8. • liver lies deep to
ribs 7–11 on the
right side and
crosses the
midline toward the
left nipple.
• moves with the
excursions of the
diaphragm and is
located more
inferiorly when
one is erect
because of gravity.
8

9. Surfaces
• Diaphragmatic surface
– Convex in shape
– Covered with visceral peritoneum, except posteriorly in the bare area of
the liver, where it lies in direct contact with the diaphragm
– Relations
• Anterior
– Diaphragm, abdominal wall, costal margin, xiphoid process
• Superior
– Diaphragm
• Posterior
– Diaphragm and lower ribs
• Right
– Diaphragm, lower ribs
• Visceral surface
– Concave in shape
– Impressions of other organs
9

10. Cont..
10

11. Cont.
Bounderies of bare area
of liver
– Coronary
ligament
• Anterior and
posterior layers
– Right triangular
ligament
– Left triangular
ligament
11

12. Cont.
12

13. Cont.
13

14. Spaces
• Subphrenic recesses
– Superior extensions of the peritoneal cavity between
diaphragm and the anterior and superior aspects of the
diaphragmatic surface of the liver.
– Separated into right and left recesses by the falciform
ligament
• Subhepatic space
• The hepatorenal recess
– It is the posterosuperior extension of the subhepatic space,
lying between the right part of the visceral surface of the
liver and the right kidney and suprarenal gland.
14

15. Cont.
15

16. Fixation
• Factors responsible for the fixation of the liver
at the RUQ of the abdomen.
– Ligaments
– Peritoneal folds
– IVC
– Suprahepatic veins
– Positive intra-abdominal pressure
16

17. Ligaments
• The liver is held in place by several ligaments
– The round ligament: the remnant of the obliterated umbilical vein and
enters the left liver hilum at the front edge of the falciform ligament
– The falciform ligament: separates the left lateral and left medial
segments along the umbilical fissure and anchors the liver to the anterior
abdominal wall
– Ligamentum venosum (Arantius’ ligament): found deep in the plane
between the caudate lobe and the left lateral segment
• It is the obliterated ductus venosus and is covered by the plate of Arantius
– Triangular ligaments (left and right): secure the two sides of the liver to
the diaphragm
– Coronary ligaments: extensions from the triangular ligaments anteriorly
on the liver
– These ligaments can be divided in a bloodless plane to fully mobilize the
liver to facilitate hepatic resection
17

18. 18

19. Cont.
• Centrally and just to the left of the GB fossa, the
liver attaches via the hepatoduodenal and the
gastrohepatic ligaments.
– The hepatoduodenal ligament is known as the porta
hepatis and contains the CBD, the hepatic artery,
and the portal vein.
• From the right side and deep (dorsal) to the porta hepatis
is the foramen of Winslow, also known as the epiploic
foramen.
– This passage connects directly to the lesser sac and allows
complete vascular inflow control to the liver when the
hepatoduodenal ligament is clamped using the Pringle
maneuver.
19

20. Cont.
20

21. Segmental Anatomy
(functional anatomy)
• Anatomically, the liver is divided in to 4 lobes
(by the falciform ligament and the left sagittal
fissure)
– Right lobe
– Left lobe
– Quadrate lobe
– Caudate lobe
21

22. Cont.
• Quadrate lobe
– It is situated on the inferior surface and is rectangular
in shape
– Bounded:
• Anteriorly by the inferior border
• Posteriorly by the porta hepatis
• On the right by the fossa for gallbladder
• On the left by the fissure for the ligamentum teres
– Functionally it is related to the left lobe of the liver
22

23. Cont.
• Caudate lobe
– Situated on the posterior surface
– Bounded:
• On the right by the groove for the IVC
• On the left by the fissure for ligamentum venosum
• Inferiorly by the porta hepatis
• Superiorly it is continuous with the superior surface
– It has 3 parts (spiegel lobe, paracaval portion, caudate
process)
– Blood supply: left portal vein (dominant), main portal vein,
right portal vein, right/left hepatic artery
– Functionally, it is separate from the right and the left lobes
of the liver
23

24. Cont.
• Functionally (in terms of blood supply and glandular secretion),
liver is grossly separated into the right and left lobes by the
plane from the GB fossa to the IVC, known as Cantlie’s line
(passing over the middle hepatic vein)
– The falciform ligament does not separate the right and left
lobes, but rather it divides the left lateral segment from the
left medial segment
• The left lateral and left medial segments also are referred
to as sections
• The right lobe typically accounts for 60% to 70% of the liver
mass, with the left lobe (and caudate lobe) making up the
remainder
24

25. Cont.
25

26. Cont.
• Couinaud (a French surgeon and anatomist) divided
the liver into 8 segments (each supplied by a single
portal triad), numbering them in a clockwise direction
beginning with the caudate lobe as segment I
• The right lobe is comprised of segments V, VI, VII, andVIII with
segments V and VIII making up the right anterior section, and
segments VI and VII the right posterior section Separated by the
right sagittal fissure.
• The left lobe is comprised of segments I, II, III,
and IV (a and b)
• Segment I: caudate lobe
• Segment II and III: left lateral section
• Segment IVa and IVb: left medial section
26

27. Cont.
27
A segment is the basic anatomic unit of
the liver

28. Cont.
28

29. Cont.
• Many anatomy textbooks refer to segment IV as
the quadrate lobe.
• Quadrate lobe is an outdated term, and the
preferred term is segment IV or left medial
segment
• Most surgeons still refer to segment I as the
caudate lobe, rather than segment I
29

30. Cont.
• Additional functional anatomy was highlighted by
Bismuth based on the distribution of the hepatic
veins.
– The 3 hepatic veins run in corresponding scissura
(fissures) and divide the liver into four sectors.
• The right hepatic vein runs along the right fissure and separates
the right posterolateral sector from the right anterolateral
sector.
• The left hepatic vein runs in the left fissure and separates the
left medial and left lateral sectors.
• The middle hepatic vein runs in the main fissure and separates
the right and left livers.
30

31. Cont.
31

32. Blood supply
• The liver has a dual blood supply consisting of the hepatic
artery and the portal vein
• The hepatic artery delivers approximately 25% (30-50% of
oxygen) of the blood supply, and the portal vein
approximately 75%.
• The “classic” or standard celiac axis arterial anatomy is
present in only approximately 76% of cases, with the
remaining 24% having variable anatomy.
– Celiac: left gastric, common hepatic, and splenic
– Common hepatic: hepatic proper and gastrodoudenal
– Hepatic proper: right gastric
32

33. Cont.
• Classic anatomy
33
• The right hepatic artery supplies
segments V to VIII and
• The left branch supplies segments II to IV

34. Cont.
• Variants (replacement or accessory)
34

35. Portal vein
• The portal vein is formed by the confluence of the
splenic vein and the SMV.
• The main portal vein traverses the portahepatis before
dividing into the left and right portal vein branches
– The left portal vein typically branches from the main portal
vein outside of the liver with a sharp bend to the left and
consists of the transverse portion followed by a 90° turn at
the base of the umbilical fissure to become the umbilical
portion before entering the liver parenchyma.
– The division of the right portal vein is usually higher in the
hilum and may be close to (or inside) the liver parenchyma
at the hilar plate.
35

36. Cont.
• Classic anatomy
36

37. Cont.
• Variant anatomy of portal vein
– 20-35% of individuals have aberrant portal venous
anatomy, with portal vein trifurcation or an
aberrant branch from the left portal vein supplying
the right anterior lobe being the most frequent
• Other
– Portal vein anterior to the neck of the pancreas and duodenum
– Entrance of the portal vein directly into the IVC
– A pulmonary vein may enter the portal vein
– There may be a congenital absence of the left branch of the portal
vein
37

38. Cont.
• Cont.
38

39. Cont.
• Accessory branches of the main portal vein
– The posterior superior pancreaticoduodenal vein
• Comes off low in an anterior lateral position and is
divided during pancreaticoduodenectomy
– Branch to caudate lobe
• Given off closer to the liver and ligated during hilar
dissection for anatomic right hemihepatectomy to avoid
avulsion
39

40. Cont.
• The portal vein drains the splanchnic blood from
the stomach, pancreas, spleen, small intestine, and
majority of the colon to the liver
• The portal vein pressure in an individual with
normal physiology is low at 3 to 5 mmHg
– In the setting of portal hypertension, the pressure can
be quite high (20 to 30 mmHg)
• This results in decompression of the systemic circulation
through portocaval anastomoses, most commonly via the
coronary (left gastric) vein, which produces esophageal and
gastric varices with a propensity for major hemorrhage
40

41. 41

42. Portosystemic anastomoses
Cont.
– Sites of anastomoses
• The short gastric veins and the left gastric
vein
• The superior hemorrhoidal plexus
• The umbilical and abdominal wall veins
• Other retroperitoneal communications like the
ascending colon, descending colon, duodenum,
pancreas, and liver (portal tributary) anastomose
with the renal, lumbar, and phrenic veins (systemic
tributaries)
42

43. 43

44. Venous drainage
• There are 3 hepatic veins that pass obliquely
through the liver to drain the blood to the
suprahepatic IVC and eventually the right atrium
– The right hepatic vein drains segments V through VIII
– The middle hepatic vein drains segment IV as well as
segments V and VIII
– The left hepatic vein drains segments II and III
– The caudate lobe is unique because its venous drainage
feeds directly into the IVC
44

45. Cont.
• In addition, the liver usually has a few small, variable short
hepatic veins that directly enter the IVC from the
undersurface of the liver
• The left and middle hepatic veins form a common trunk
approximately 95% of the time before entering the IVC,
whereas the right hepatic vein inserts separately (in an
oblique orientation) into the IVC
• There is a large inferior accessory right hepatic vein in 15%
to 20% of cases that runs in the hepatocaval ligament
– This can be a source of torrential bleeding if control of it is lost
during right hepatectomy
45

46. Cont.
46

47. Cont.
47

48. Lymphatics
• Pathways
– Superficial lymphatics: in the subperitoneal fibrous capsule of the
liver
– Deep lymphatics: in the connective tissue that accompany the
ramifications of the portal triad and hepatic veins
• Lymph produced within the liver drains via the perisinusoidal space of
Disse and periportal clefts of Mall
• Final drainage
– To larger lymphatics that drain to the hilar cystic duct lymph node
(Calot’s triangle node), LNs around hepatic artery, celiac lymph
nodes, and finally in to the chyle cistern
– Superficial lymphatics from the posterior aspects of the
diaphragmatic and visceral surfaces of the liver drain into phrenic
lymph nodes or into the posterior mediastinal lymph nodes
48

49. 49

50. Inervation
• The parasympathetic innervation of the liver comes from
the left vagus, which gives off the anterior hepatic
branch, and the right vagus, which gives off the
posterior hepatic branch.
• The sympathetic innervation involves the greater
thoracic splanchnic nerves and the celiac ganglia,
although the function of these nerves is poorly
understood.
• The denervated liver after hepatic transplantation seems
to function with normal capacity.
50

51. 51

52. Cont.
• A common source of referred pain to the right
shoulder and scapula as well as the right side or
back is the right phrenic nerve, which is
stimulated by tumors that stretch Glisson’s
capsule or by diaphragmatic irritation
52

53. Bile Duct and Hepatic Ducts
• Within the hepatoduodenal ligament, the CBD
lies anteriorly and to the right
• In general, the hepatic ducts follow the arterial
branching pattern inside the liver
• The GB sits adherent to hepatic segments IVB
(left lobe) and V (right lobe)
53

54. Microscopic anatomy
• The liver lobule
– It is the structural/basic functional unit of the liver
which is hexagonal and constructed around a central
vein that empties into the hepatic veins and cornered by
the portal 4 to 6 tracts
– The liver contains 50,000 to 100,000 individual lobules
– It has 3 zones (based upon oxygen and nutrient supply)
• Zone 1 (periportal)
• Zone 2 (intermidiate)
• Zone 3 (perivenular)
54

55. Cont.
55

56. Cont.
• Hepatocyte (94% of liver parenchyma)
– Sinusoidal membrane (70% of surface area)
• For exchange of materials between space of Disse (contain
stellate cells) and intracellular space
– Canalicular membrane (15%)
• For exchange with the biliary canaliculi
– Lateral membrane (15%)
• Separated from neighboring hepatocytes by tight junctions
56

57. Cont.
• Hepatic sinusoid
– Specialized capillaries without a basement membrane
– Lined by sinusoidal endothelial cells & other different
types of sinusoidal lining cells
– Perforated by abundant small fenestrae
– Receive blood from both hepatic artery & Portal vein
– Hepatic sinusoid lining cells (6 % of all liver parenchy
ma)
• Endothelial cells, Kupffer cells, hepatic stellate
cells (Ito cells, fatstoring cells), pit cells (intrahepatic
lymphocytes)
57

58. Cont.
58

59. Cont.
• Bile canaliculi
– Drain in to bile ductules and then bile ducts
59

60. Anatomy of Gall
Bladder
• Pear shaped sac
• 7-10cm long
• Capacity 30-50ml …..distended up to
300ml
• Located on GB fossa
• Four anatomic areas
• Peritoneum covers fundus and inferior
surface……..suspended, intrahepatic
02/11/2022 60

61. Histology
• Lined by single folded tall columnar epi.
• Tubuloalveolar glands in neck and
infundibulum
• Muscular layer not well developed
• Perimuscullar subserosa contains CT, NVs,
lymphatic, and adipocytes
• Serosa covers except embed in liver
• GB lacks muscularis mucosa and Sub Mucosa
02/11/2022 61

62. 02/11/2022 62
Arterial supply
Supplied by cystic artery Br.
From RHA (>90%)
Venous return
Small veins enter to liver
Large cystic vein drain to
PV….rare
Lyphatics
Into nodes at neck of GB
Nerve supply
By Vagus nerve and Celiac
plexus

64. 64

65. GB and CD anomaly
 Abnormal position of GB
*rudimentary
*intrahepatic
*anomalous form
*duplicated
 Isolated absence of GB
very rare
incidence…0.03%
 Left side GB with CD
empty into RHD
 Ducts of Lushcka
 Accessory RHD……5% of cases
02/11/2022 65

66. 02/11/2022 66

67. Anomalies of HA and CA
Quite common
Occur in 50% cases
Different forms
*CA from RHA …..in 90%
*Two RHA(CHA, SMA)…..in 5% cases
*RHA off SMA
02/11/2022 67

68. 02/11/2022 68

69. Cont.
• Cont.
69

70. Cystic duct
• Variations of the cystic duct and its point of
union with the CHD are surgically important
• The length of the cystic duct is quite variable
– It may be short or absent and have a high union with
the hepatic duct, or long and run parallel, behind, or
spiral to the main hepatic duct before joining it,
sometimes as far as at the duodenum
70

71. Cont.
• Based on length
– Absent
– Short
– Long
• Based on insertion
– High
– Low
– Rotated (spiral)
• Anterior to CBD
• Posterior to CBD
71

72. Bile ducts
• Small ducts (of Luschka) may drain
directly from the liver into the body of
the gallbladder
– If present, but not recognized at the time
of a cholecystectomy, a bile leak with the
accumulation bile (biloma) may occur in
the abdomen
– Frequency ranges from 1% to 50% in
published series
• An accessory right hepatic duct occurs
in about 5% of cases
– ?Posterior sectoral duct
72

73. Arteries
• Anomalies of the hepatic artery and the cystic
artery are quite common, occurring in as many as
50% of cases
– RHA
• In about 5% of cases, there are two RHAs
– One from the common hepatic artery and the other from the SMA
• In about 20% of patients, the RHA comes off the SMA
• The RHA may course anterior to the common duct
– Cystic artery
• The cystic artery arises from the RHA in about 90% of cases,
but may arise from the left hepatic, common hepatic,
gastroduodenal, or SMA
73

74. Cont.
• Cystic artery
A. From right hepatic aa - 80–90%
B. From right hepatic aa (accessory
or replaced) from SMA - 10%
C. Two cystic aa’s (right hepatic aa,
and common hepatic aa) - rare
D. Two cystic aa’s (right hepatic aa,
and left hepatic artery) - rare
E. The cystic aa running anterior to
the CHD - rare
F. Two cystic arteries arising from
the right hepatic artery - rare
74

75. Physiology of liver
• Liver functions
– Metabolism
• Nutrient
• Bilirubin
• Detoxification
– Secretion/excretion
• Bile, erythropoeitin, waste products
– Production
• Proteins
– Storage
• Nutrients, vitamins, minerals
– Immunologic response
• RES
• Acute phase reactants (CRP, globulins)
75

76. Gallbladder Function
• The gallbladder, the bile ducts, and the
sphincter of Oddi act together to store and
regulate the flow of bile
• The main function of the gallbladder is to
concentrate and store hepatic bile and to
deliver bile into the duodenum in response to a
meal.
76

77. Reference
• Schewartz,11th edition
• netters,clinical anatomy,2nd edition
• Moore clinical oriented anatomy
77