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Chapter 2
The cystic plate has been described above. Small
bile ducts may penetrate the cystic plate to enter
the gallbladder. These ‘ducts of Luschka’ are very
small, usually submillimetre accessory ducts.
However, when divided during cholecystectomy,
postoperative bilomas may occur if they are not
visualised and occluded. Bilomas and haemorrhage
may also be caused by penetration of the cystic plate
during dissection. In about 10% of patients there
is a large peripheral bile duct immediately deep to
the plate, disruption of which will cause copious
bile drainage. The origin of the middle hepatic vein
is also in this location, and if it is injured massive
haemorrhage may ensue. There is areolar tissue
between the muscularis of the gallbladder and the
cystic plate. At the top of the gallbladder the layer
is very thin. This areolar layer thickens if retrograde
dissection from the top of the gallbladder in a
medial direction is performed. If areolar tissue is left
on the cystic plate, the surgeon will arrive on the
posterior surface of the cystic artery and cystic duct
(Fig.2.17, dotted arrow). Conversely, if dissection
is performed on the cystic plate leaving the areolar
tissue on the gallbladder, the surgeon will arrive at
the right portal pedicle (Fig.2.17, solid arrow). If
this is not anticipated, structures in the right portal
pedicle may be injured. This dissection method is
significantly more challenging in the presence of an
inflamed gallbladder or Mirizzi syndrome, when
the areolar tissue between the gallbladder and cystic
plate is fused together.
Extrahepatic bile ducts
The common hepatic duct (CHD) is a structure
formed by union of the right and left hepatic ducts.
The union normally occurs at the right extremity of
the base of Sg4, anterior and superior to the portal
vein bifurcation. The CHD travels in the right edge
of the hepatoduodenal ligament for 2–3 cm, where
it joins the cystic duct to form the common bile
duct (CBD). The latter has a supraduodenal course
of 3–4 cm and then passes behind the duodenum to
run in or occasionally behind the pancreas to enter
the second portion of the duodenum. Details of its
lower section and relation to the pancreatic duct are
described in the final section of this chapter. The
external diameter of the common bile duct varies
from 5 to 13 mm when distended to physiological
pressures. However, the duct diameter at surgery,
i.e. in fasting patients with low duct pressures, may
be as small as 3 mm. Radiologically, the internal
duct diameter is measured on fasting patients.
Under these conditions the upper limit is normally
8 mm. Size should never be used as a sole criterion
for identifying a bile duct. Caution is required in
situations where a structure seems larger than
expected. Although the cystic duct may be enlarged
due to passage of stones, the surgeon should take
extra precaution before dividing a ‘cystic duct’
that is greater than 2 mm in diameter because the
common bile duct can be 3 mm in diameter and
aberrant ducts may be smaller.
Anomalies of extrahepatic bile ducts
As already noted, there are biliary anomalies of
the right and left ductal systems that can affect
the outcome of hepatic surgery. The same is true
for biliary surgery. The most important clinical
anomaly is low insertion of right hepatic ducts
referred to above. Because of its low location, it may
be mistaken as the cystic duct and be injured during
cholecystectomy. This is even more likely to occur
when the cystic duct unites with an aberrant duct as
opposed to joining the common hepatic duct. Left
hepatic ducts can also join the common hepatic duct
at a low level. They are less prone to injury since
dissection during cholecystectomy is on the right
side of the biliary tree.
Extrahepatic arteries
The course of these arteries has been described
above. Anomalies of the hepatic artery are
important in gallbladder surgery. Normally the
right hepatic artery passes posterior to the bile duct
(80%) (Fig. 2.19a) and gives off the cystic artery in
the hepatocystic triangle. However, in 20% of cases
the right hepatic artery runs anterior to the bile duct
(Fig. 2.19b–f). The right hepatic artery may lie very
close to the gallbladder and chronic inflammation
can draw the right hepatic artery directly on to
the gallbladder, where it lies in an inverse U-loop
and is prone to injury. In the ‘classical injury’ in
laparoscopic cholecystectomy when the common
bile duct is mistaken for the cystic duct, an associated
right hepatic artery injury is very common.
Blood supply of bile ducts
Many studies, dating back to the 19th century, have
examined the blood supply of the extrahepatic bile
ducts in cadaveric specimens. A key observation made
by Rappaport is that the bile ducts are supplied by
the hepatic artery only,
a dual blood supply from the hepatic artery and the
portal vein. The arterial blood supply can be thought
of as having three anatomical elements. The first
consists of afferent vessels from the hepatic artery
and its branches (
is longitudinal arteries that run parallel to the long
axis of the bile duct and that receive blood from the
afferent vessels (
arterial plexus encasing the bile ducts that receives
blood from the marginal arteries (
branches of the plexus pierce the bile duct wall to
supply the capillaries of the bile duct.
16
unlike the liver, which has
Fig. 2.20a). The second element
Fig.2.20b). The third element is an
Fig. 2.20c). Tiny
32
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Hepatic, biliary and pancreatic anatomy
A3
9
ar
teries to
Figure2.20 • (a) The supplying arteries. All arteries shown
A4
RHA
CA
SMA
a
PSPDA
GDA
Transverse hilar
marginal artery
LLSA
LHA
PHA
RGA
CHA
can all give branches to the marginal arteries or in some cases
directly supply the epicholedochal plexus. (A2, A3, A4, arteries
to Sg2, 3 and 4; CA, cystic artery; CHA, common hepatic
A2
artery; GDA, gastroduodenal artery; LHA, left hepatic artery;
LLSA, left lateral sectional artery; PHA, proper hepatic artery;
PSPDA, posterior superior pancreaticoduodenal artery, the
most important and constant artery; RHA, right hepatic artery).
Replaced arteries arising from the superior mesenteric artery
may also supply the bile ducts. (b) Marginal arteries. Marginal
arteries are disposed at 3 and 9 o'clock (and occasionally at
12 o'clock) on the common bile duct/common hepatic duct.
The hilar marginal artery runs across the top of the confluence
of the right and left hepatic ducts. (c) Epicholedochal plexus.
The epicholedochal plexus is supplied by the marginal arteries.
Adapted from Strasberg SM, Helton WS. An analytical
review of vasculobiliary injury in laparoscopic and open
cholecystectomy. HPB 2011;13(1):1–14. With permission from
John Wiley & Sons.
o' clock marginal
tery
b
c
Hilar component of the
epicholedochal plexus
3 o' clock marginal
artery
Arterial twigs from
supplying ar
marginal arteries
Arterial twigs from
marginal arteries to
epicholedochal plexus
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33
Chapter 2
The afferent vessels are branches of the hepatic
arteries and less commonly of the superior
mesenteric artery or other upper abdominal arteries.
The most constant and important artery supplying
the bile duct is the posterior superior pancreaticoduodenal artery, usually the first branch of the
GDA. Arterial branches pass to the duct as the
artery winds around the lower end of the duct.
These branches supply much of the retroduodenal
and intrapancreatic bile duct, but also ascend the
bile duct to supply the supraduodenal bile duct. The
lowest portion of the duct near the ampulla is also
supplied by the anterior superior pancreatic artery
from the inferior pancreatico-duodenal artery.
Other vessels that commonly send afferents to the
supraduodenal duct are the proper hepatic artery,
cystic artery and artery to Sg4. Furthermore, body
wall collaterals such as phrenic arteries can at times
supply the bile ducts (as well as the liver) since bile
duct infarction is much more common when there
is occlusion of the common hepatic artery after a
transplant than it is in an in situ liver. The notion
that the extrahepatic bile duct is supplied by arteries
that join it only at the bottom and top of its course is
incorrect. Supplying arteries from the cystic artery,
right and left hepatic arteries and proper hepatic
artery may also supply it.
The afferent vessels usually supply the longitudinal
or ‘marginal’ arteries that run parallel to the long axis
of the bile ducts (also called ‘marginal anastomotic
17
loop’).
less commonly, at 12 o'clock on the common bile
duct/common hepatic duct, or run across the top of
the confluence and the right and left bile ducts. This
‘hilar marginal artery’ has been called the ‘caudate
arcade’ or ‘communicating arcade’. This artery is of
great importance in maintaining blood supply to
the liver when one hepatic artery (right or left) is
occluded.
‘epicholedochal plexus’, a fine arterial plexus that
lies on and surrounds the entire common bile duct
and the left and right bile ducts. The latter is the
hilar component of the epicholedochal plexus. The
vessels of the plexus tend to run along the long axis
of the ducts so that on the common duct many
of the vessels are vertical while those around the
confluence and the right and left ducts are disposed
horizontally. In the portion of the biliary tree that
lies adjacent to the hilar plate or which has entered
the fibrous sheaths, the epicholedochal plexus
lies between the sheath and the wall of the bile
duct. Dissection in this plane has the potential to
devascularise bile ducts.
of the duct. For instance, if the duct is transected at
the level of the duodenum, ischaemia of a portion of
the bile duct above this level may occur since blood
These vessels are disposed at 3 and 9 or,
18
The third element of this system is the
19
Transection of the bile duct may result in ischaemia
flow originating from the superior pancreaticoduodenal artery and passing up along the marginal
artery is cut off. Similarly, in a high transection at
the level of the confluence, the lower cut end of
the duct may become ischaemic. This problem is
thought to be an important contributory cause to
the frequent failure of choledocho-choledochotomy
as a form of biliary reconstruction. To avoid this
problem, the bile duct is trimmed back to within
1 cm of the confluence and a hepatico-jejunostomy
is fashioned.
Pancreas
Embryological development of the
pancreas
The thickening of the endoderm on the dorsal
side of the gut tube opposite the hepatic bulge
marks the development of the dorsal pancreas. The
bulging of the dorsal pancreas into the mesenchyme
becomes paired with the growth of the ventral
foregut endoderm, which becomes the ventral
pancreas. During the clockwise rotation of the gut
tube, the ventral and dorsal buds come together
and subsequently fuse. Pancreatic progenitor cells
undergo further differentiation and commit to
the major pancreatic lineages depending on either
endocrine or exocrine pathways. Acinar cells are
produced and proliferate around the epithelial tip,
whilst islets of Langerhans are derived at a later
stage, and continue to develop beyond the first week
of the postnatal period.
Anatomical structure and
functions of the pancreas
The pancreas is a retroperitoneal organ lying
obliquely across the upper abdomen so that the tail
is superior to the head. It is approximately 22 cm
in length. The head of the pancreas is discoid in
shape and terminates inferiorly and medially in the
hook-like uncinate process. The neck, body and
tail are shaped like a flattened cylinder, sometimes
somewhat triangular in cross-section with a flat
anterior and pointed posterior surface. These
divisions of the organ are somewhat arbitrary,
but the neck of the pancreas sits anterior to the
superior mesenteric and portal vein. Normally the
consistency of the gland is soft.
The pancreas has two key functions, which are
endo- and exo-crine functions. For the exocrine
function, pancreatic juice is secreted from acinar
cells to intralobular ducts, which in turn drain
into the main pancreatic duct and then to the
34
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Hepatic, biliary and pancreatic anatomy
duodenum. The enzyme produced from the
acinar cell is secreted as an inactive form, called
zymogen, which is then cleaved and activated by
enteropeptidase upon reaching the duodenum
Fig.2.21).
(
The endocrine function of the pancreas is
contributed by four types of pancreatic islet cells,
namely α-(alpha-)cells (secreting glucagon), β-(beta-)
cells (insulin), δ-(delta-)cells (somatostatin) and
γ-(gamma-)cells (pancreatic polypeptide). Insulin
acts to decrease blood glucose level, whereas
glucagon balances it out. These hormones
are secreted by the islet cells directly into the
bloodstream, and function independently from the
exocrine role of the pancreas.
Pancreatic ducts
The prevailing anatomical pattern of the pancreatic
duct is the result of union of the ventral main duct
(Wirsung) with the dorsal accessory duct (Santorini),
along with partial regression of the dorsal duct in
the head. The ‘genu’ of the duct (genu = knee) is the
bend in the duct where the ventral duct joins the
dorsal duct. In the prevailing pattern, both ducts
communicate with the duodenum, the dorsal duct
entering at the minor papilla approximately 2 cm
above and 5 mm anterior to the major papilla. Other
ductal patterns are possible that involve various
degrees of dominance or regression of portions of
the ducts in the head of the pancreas. For instance,
the ducts may not unite, resulting in separate
drainage from the ventral and dorsal pancreas
(pancreas divisum), the dorsal duct may lose its
connection to the duodenum; or the dorsal duct in
the head may lose its connection to the rest of the
ductal system and drain only a small section of the
head into the duodenum. Alternatively, the ventral
duct may regress and the dorsal duct drain more or
all of the pancreas through the minor ampulla. The
uncinate process is served by its own duct, which
joins the main pancreatic duct 1–2 cm from its entry
into the duodenum.
The pancreatic duct (and pancreas) are often
referred to as proximal (head) and distal (tail).
These may be confusing terms – as may the terms
proximal and distal bile duct. The bile duct nearest
to the ampulla is commonly referred to as ‘distal’,
but the pancreatic duct in this region as ‘proximal’.
An alternative is to refer to the pancreatic portion
or lower bile duct and the upper extrahepatic or
hilar bile duct. For the pancreas, the duct may be
referred to as the ‘pancreatic head duct’, ‘pancreatic
body duct’, etc.
The ventral duct usually joins the common bile
duct to form a common channel several millimetres
from the ampulla of Vater, usually within the wall of
the duodenum. The bile duct traverses the duodenal
wall obliquely and the pancreatic duct at a rightangle. Each duct and the common channel have
their own sphincters. The common channel may
Proenteropeptidase
Acinar cell
Trypsinogen
Enteropeptidase
Trypsin
Chymotrypsinogen
Proelastase
Procarboxypeptidase
Figure2.21 • Pancreatic zymogen activation cascade. Trypsinogen is secreted from the acinar cells. Upon reaching
the duodenum, trypsinogen is cleaved and activated by enteropeptidase to become trypsin, which then activates
chymotrypsinogen, proelastase, procarboxypeptidase. The formation of trypsin also allows the cleavage of more
trypsinogen and the precursor of enteropeptidase.
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Chymotrypsin
Elastase
Carboxypeptidase
35
Chapter 2
be longer or absent, with both ducts entering the
duodenum separately, the pancreatic duct more
inferiorly. In performing a sphincteroplasty, it is
advisable to open the common opening superiorly
(10–12 o'clock position in the mobilised duodenum)
to avoid the orifice of the pancreatic duct (4
o'clock). The ampulla is normally at the midpoint of
the second part of the duodenum. It is rarely higher
but can be as low as the midpoint of the third part
of the duodenum. When the dorsal duct has its own
communication with the duodenum, it is found at
the ‘minor papilla’, about 2 cm proximal and 1 cm
anterior to the major papilla.
Blood supply of the pancreas
The arterial supply of the pancreas consists of
two vascular systems, one supplying the head and
uncinate, and the other the body and tail. The neck
is a watershed area between these two vascular
systems.
supplied by the pancreatico-duodenal arcade, which
consists of two to several loops of vessels that arise
from the superior pancreatico-duodenal (branch
of the GDA) and inferior pancreatico-duodenal
(branch of the SMA) arteries. The arcades run on
the anterior and posterior surface of the pancreas
20
The head and uncinate process are
next to the duodenum, the anterior arcade lying
somewhat closer to the duodenum. The second
system arises from the splenic artery, which gives
rise to three arteries into the dorsal surface of the
Fig.2.22). The dorsal pancreatic artery is the
gland (
most medial of the three and the most important. It
anastomoses with the pancreatico-duodenal arcade
in the neck of the pancreas. It is the most aberrant
artery in the upper abdomen and may arise
from vessels that are routinely occluded during
pancreatico-duodenectomy, which may account in
part for fistula formation after this procedure.
This unique arterial arcade between the inferior
pancreatico-duodenal and the GDA at the head
of the pancreas provides an additional surgical
option in achieving resectability for pancreatic body
tumours encasing the coeliac axis. By resecting the
coeliac axis in these rare circumstances, the liver
will then rely on the backflow arterial supply from
the GDA to the hepatic artery proper, and that GDA
will also provide the only arterial supply to the
stomach via the gastroepiploic artery, since the left
gastric and splenic arteries will have been sacrificed
during the coeliac axis resection. This procedure is
known as the ‘Appleby’ procedure, which was first
described by Lyon Appleby in 1953.
21
a
c
d
i
j
Figure2.22 • Arterial blood supply to the pancreas. The dorsal pancreatic artery is shown shaded. Alternative origins
of the artery are shown as black stumps. Key: a, coeliac artery; b, common hepatic artery; c, right hepatic artery; d,
gastroduodenal artery; e, splenic artery; f, superior mesenteric artery; g, middle colic artery; h, right hepatic artery
(aberrant); i, superior pancreatico-duodenal artery; j, right gastroepiploic artery; k, inferior pancreatico-duodenal artery; l,
dorsal pancreatic artery (DPA); m, right anastomotic branch of DPA to superior part of pancreatico-duodenal arcade; o,
left anastomotic branch of DPA becomes transverse pancreatic artery; p, pancreatica magna artery; q, caudal pancreatic
artery; r, transverse pancreatic artery.
© Washington University in St Louis.
b
l
m
h
k
o
n
f
e
p
r
g
q
36
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Hepatic, biliary and pancreatic anatomy
Anterosuperior
pancreatico-duodenal vein
Posterosuperior
pancreatico-duodenal vein
Right gastroepiploic vein
Superior right colic vein
Portal vein
pancreatico-duodenal vein
Anteroinferior
pancreatico-duodenal vein
Gastrocolic trunk
Ileocolic vein
Pyloric vein
Coronary vein
Splenic vein
Inferior mesenteric vein
Posteroinferior
Middle colic vein
Superior mesenteric vein
First jejunal vein
Jejuno/intermediate vein
Figure2.23 • Venous drainage of the pancreas. Variations in the relation of the portal, splenic, superior mesenteric and
inferior mesenteric veins are shown at the bottom.
Adapted from Vickers SM, Arnoletti JP, Brunicardi FC, Andersen DK. Pancreas anatomy and physiology. In: Mulholland
MW, Lillemoe KD, Doherty GM, editors. Greenfield's surgery: scientific principles and practice. 4th edition. Philadelphia:
Lippincott Williams & Wilkins; 2006. Copyright © 2006 Lippincott Williams & Wilkins.
Venous drainage generally follows the arterial
supply (
the pancreas drain into the splenic vein, which lies
partly embedded in the posterior surface of the
gland. These veins are short and fragile. The right
gastroepiploic and anteroinferior pancreaticoduodenal veins provide drainage for the head
and uncinate process. These two tributaries form
the gastrocolic trunk, which in turn drains into
the superior mesenteric vein (SMV) on the right
lateral side, and then to the portal vein (PV) above
the porto-splenic confluence. The gastrocolic
trunk is a key tributary that is ligated during
pancreatico-duodenectomy. A nearly constant
posterosuperior pancreatico-duodenal vein enters
the right lateral side of the portal vein at the level
of the duodenum. During the isolation of all
venous tributaries prior to performing a SMV/
PV resection, it is important to be mindful of the
Portal vein
Splenic vein
Superior
mesenteric vein
Inferior
mesenteric vein
Fig.2.23). The veins of the body and tail of
Portal vein
Splenic vein
Superior
mesenteric vein
Inferior
mesenteric vein
insertion of the coronary vein, which provides
drainage for the left gastric vein immediately
above the porto-splenic confluence. The inferior
mesenteric vein (IMV) normally drains into the
splenic vein. However, the IMV can occasionally
drain directly to the SMV, and can be damaged
during surgical dissection.
Lymphatics of the pancreas
For surgical purposes, the lymphatic drainage
of the pancreas is best considered with respect to
resection of the pancreatic head and resection of the
pancreatic body and tail. Nomenclature for nodal
stations is currently based on the classification of
the Japanese Pancreas Society as recommended
by the International Study Group on Pancreatic
Surgery (ISGPS).
There is a ring of nodes around the pancreas
that drain the adjacent sections of the gland and
22
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37
Chapter 2
are denoted by various lymph node stations (Ln),
depending on their location.
23
The lymphatics of the
head and uncinate process drain into lymph nodes
in the pancreatico-duodenal groove anteriorly
(Ln17) and posteriorly (Ln13), and infrapyloric
nodes inferiorly (Ln6). These in turn drain into
nodes adjacent to the common bile duct (Ln12)
and hepatic artery superiorly (Ln8), and into nodes
along the SMA (Ln14), coeliac axis (Ln9) and aorta
(axial nodes). Understanding these lymph node
stations is important as current practice is a standard
lymphadenectomy for pancreatico-duodenectomy,
which does not include coeliac (Ln9), splenic (Ln11)
and left gastric (Ln7) nodes.
The lymphatics of the body and tail are shown in
Fig.2.24. These are lymph nodes around the splenic
hilum (Ln10), splenic artery (Ln11) and inferior
border of body/tail of pancreas (Ln18). Resection of
Ln9 is only indicated in tumours involving the body
of the pancreas.
Anatomical relations and ligaments of the
pancreas
The pancreas is a deeply seated organ that, unlike
the liver and most of the biliary tree, is not obvious
when opening the abdomen. The anatomical
relations of the pancreas are very important in
pancreatic surgery. The structures emphasised in
the following section are those that are commonly
invaded by tumours.
The pancreas lies in the pararenal space anterior
to the anterior renal fascia and behind the
peritoneum. Posteriorly, the pancreas is related, from
right to left, to the right kidney and perinephric fat,
IVC and right gonadal vein, aorta, left renal vein
(slightly inferior), retropancreatic fat, left adrenal
gland and the superior pole of the left kidney. All
of the former structures lie in the perirenal space
and behind the anterior renal fascia. In the case
of oncological resections, the plane of dissection
should be behind the anterior renal fascia in order to
12b
12c
Figure2.24 • Japan Pancreas Society nomenclature of peripancreatic lymph nodes.
Adapted from Japan Pancreas Society. Classification of pancreatic carcinoma. 2nd English edition. Tokyo: Kanehara &
Co. Ltd; 2003.
12b
13a
12a
7
14b
15
14a
14c
9
14d
16
11p
11d
18
2
5
8a
8p
6
17a
17b
13b
10
38
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Hepatic, biliary and pancreatic anatomy
maximise the chance of obtaining negative margins
as described for the radical antegrade modular
pancreatosplenectomy (RAMPS) procedure.
24
The SMV and portal vein are posterior relations
to the neck of the pancreas, and splenic vein to the
body and tail. The SMA is a posterior relation of
the junction of the neck and body of the gland lying
posterior and medial to the SMV. The SMA and
SMV are both related to the uncinate process and
give branches into and receive tributaries from the
uncinate process, respectively. Often the uncinate
veins enter a large tributary of the SMV, the first
jejunal vein, which also abuts the uncinate process.
These short arteries and veins are of importance
surgically as they are divided when the head of
the pancreas is resected. The coeliac artery rises
vertically superior to the SMA close to the superior
edge of the pancreas, where it gives off the common
hepatic artery and the splenic artery. The former
runs anteriorly and to the left in approximation
to the superior border of the pancreas. At the
point where the artery passes in front of the portal
vein, it divides into the gastroduodenal artery,
which passes anterior to the neck of the pancreas,
sometimes buried within it. It terminates in the right
gastroepiploic artery that rises in a fold of tissue
toward the pylorus, a fold that also contains the
right gastroepiploic vein and subpyloric nodes. The
splenic artery snakes along the superior border of
the pancreas to leave it 2–3 cm from the termination
of the pancreas.
The head of the pancreas is wrapped in the first
three parts of the duodenum and the tail ends in
relation to the splenic hilum. There is variability
in the proximity of the tail of the pancreas to
the spleen. In some cases the pancreas terminates
2 cm from the splenic substance and in others it
abuts it. The anterior surface of the body and tail
of the pancreas is covered by peritoneum, which
is the posterior wall of the lesser sac, and then
by the posterior wall of the stomach anterior to
this. The transverse mesocolon is related to the
inferior border of the pancreas, and the right and
left extremities of the transverse colon are related
to the head and tail of the gland. The inferior
mesenteric vein is related to the inferior border of
the neck of the pancreas and may pass behind it
to enter the splenic vein or turn medially to enter
the SMV.
The pancreas is normally accessed surgically
by entering the lesser sac either by division of
the greater omentum below the gastroepiploic
arcade or by releasing the greater omentum from
its attachment to the transverse colon. When the
lesser sac is entered, the anterior surface of the
neck, body and tail are often visible, but may be
obscured by congenital filmy adhesions to the
posterior wall of the stomach. To expose the head
of the pancreas it is necessary to mobilise the right
side of the transverse colon and hepatic flexure
inferiorly and to divide the right gastroepiploic
vein. The latter crosses the inferior border of the
pancreas to join with the middle colic vein to form
the gastrocolic trunk, which then enters the SMV.
For complete exposure, e.g. for a Frey procedure,
the right gastroepiploic artery is also divided and it
and the subpyloric nodes are swept upwards off the
pancreas. To access the SMV at the inferior border
of the pancreas the peritoneum at the inferior
border of the neck is divided and the dissection is
carried inferiorly and laterally to open a groove
between the uncinate process and the mesentery.
Division of the right gastroepiploic vein at the
inferior border of the pancreas greatly facilitates
this manoeuvre. Normally no veins enter the SMV
or PV from the posterior surface of the neck of the
pancreas. Consequently the neck of the pancreas
can be separated from the anterior surface of the
SMV/PV in this avascular plane. The peritoneum
at the inferior border of the neck, body and tail
of the pancreas is avascular, and there are few
vascular connections between the back of the body
and tail of the pancreas and retroperitoneal tissues.
As a result the pancreas may be readily dissected
free from the retroperitoneum. The splenic vein is
partly embedded in the back of the pancreas from
the point that it reaches the gland on the left to
about 1 cm from its termination at its confluence
with the SMV.
Innervation of the pancreas
The pancreas is a highly innervated visceral organ.
Pancreatic nerves are sensitive to both chemical
and mechanical stimuli. These nerves transmit
nociceptive and visceral afferent signals to the
coeliac plexus, which is the largest of the three
plexuses of the sympathetic system. Normally,
the preganglionic efferent fibres exit the spinal
cord to form the sympathetic chain. Instead of
synapsing at the sympathetic chain, the greater,
lesser and least splanchnic nerves pass through
the sympathetic chain to form the coeliac ganglia,
and provide the major preganglionic contribution
to the coeliac plexus. The parasympathetic supply
of the pancreas is provided by the left and right
vagal trunks, which do not connect at the coeliac
ganglia. This coeliac plexus most commonly
consolidates around the origin of the coeliac axis
and SMA.
An understanding of this pancreatic innervation
has led to the development of various non-surgical
and surgical techniques for treating pain in chronic
pancreatitis. These include the coeliac plexus block
most commonly performed under endoscopic
guidance
splanchnicectomy and ganglionectomy.
25
26
and selective pancreatic denervation by
27,28
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39
Chapter 2
Key points
• A prevailing pattern of hepatic, biliary and pancreatic anatomy exists but variations (anomalies) are
frequent.
• All HPB operations should be conducted with the strong suspicion that an anatomical anomaly may
be present.
Full reference s available at http://
expertconsult.inkling.com
Key references
2. Terminology Committee of the IHPBA. The
Brisbane 2000 Terminology of Liver Anatomy and
Resections. HPB 2000;2:333–9.
The Scientific Committee of the IHPBA created a
Terminology Committee to deal with the confusion in
nomenclature of hepatic anatomy and liver resections.
The resulting terminology is presented in this paper.
This use of agreed anatomical and surgical terms
permits a meaningful and consistent approach to
liver resection terminology in all clinical and academic
writing.
14. Schnitzbauer AA, Lang SA, Goessmann H, et al.
Right portal vein ligation combined with in
situ splitting induces rapid left lateral liver lobe
hypertrophy enabling 2-staged extended right
hepatic resection in small-for-size settings. Ann Surg
2012;255:405–14. PMID: 22330038.
First report of a novel two-stage hepatic resection
performing surgical exploration, portal vein ligation, and
in-situ splitting, resulting in marked and rapid hypertrophy
of functional liver tissue enabling curative resection of
marginally resectable liver tumours or metastases.
15. Strasberg SM, Brunt LM. Rationale and use
of the critical view of safety in laparoscopic
cholecystectomy. J Am Coll Surg 2010;211:132–8.
PMID: 20610259.
This paper describes the use of the critical view
of safety (CVS) method of identification of the
cystic duct and cystic artery during laparoscopic
cholecystectomy, in order to minimise the risk of
common bile duct injury.
22. Tol JA, GoumaDJ, Bassi C, etal. Definition of a
standard lymphadenectomy in surgery for pancreatic
ductal adenocarcinoma: a consensus statement
by the International Study Group on Pancreatic
Surgery (ISGPS). Surgery 2014;156(3):591–600.
PMID: 25061003.
This paper describes the lymph node stations surrounding
the pancreas, and provides the definitions required
for standard lymphadenectomy in surgery for ductal
adenocarcinoma located in different parts of the pancreas.
40
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3
Staging and assessment of hepatobiliary malignancies
Steve M.M. de Castro
Otto M. van Delden
Olivier R.C. Busch
Introduction
Tumour staging including assessment of potential
metastases in patients with HPB malignancy is of the
utmost importance. Patient selection should ideally
identify those who might benefit from surgery and
those who will not. Palliation for the majority of
patients with unresectable or metastatic disease can
be undertaken using minimally invasive techniques
(i.e. endoscopic or percutaneous biliary stenting,
radio- and/or chemotherapy). Technological
advances have changed the approach to evaluate
patients with suspected HPB malignancies. Modern
state-of-the-art imaging now allows physicians
to focus on two key questions in patients with
suspected HPB tumours. Is there really a malignant
tumour present (diagnosis)? If so, can it be removed
with an R0 resection (staging)?
This chapter focuses on the diagnostic work-up of
patients with the most common HPB malignancies
and discusses the staging and assessment, mainly
focusing on resectability.
Colorectal liver metastases
Imaging of colorectal liver metastases (CRLM) is
important in patient assessment for several reasons.
Firstly, to detect all the liver metastases present with
their exact location within the liver, in order to
maximise the chance of achieving complete clearance
of disease at surgery. Secondly, to characterise any
benign liver lesions that may be present, so as to
avoid unnecessary surgical procedures. Thirdly,
to provide anatomical information necessary to
perform a complete and safe resection or ablative
procedure.
Transabdominal ultrasound
Ultrasound has a diagnostic sensitivity of only
36–61% for detecting lesions measuring 1–2 cm
even when performed by experienced radiologists.1
It is very useful in guiding fine-needle aspiration
(FNA) to confirm unresectability by cytopathology.
However, FNA has a risk of seeding metastases in
up to10% of patients and is associated with a risk of
false-negative results, which does not justify its use
in patients suitable for potentially curative therapy.
A meta-analysis of the performance of ultrasound
for CRLM found a pooled sensitivity of 63% (95%
CI 56–70%; five studies) with a specificity of 97.6%
(95% CI 95.6–99.5%; four studies).
Ultrasound can be very useful as a problemsolving tool when computed tomography (CT) or
magnetic resonance imaging (MRI) is uncertain.
Targeted ultrasound of a suspicious lesion can
often discriminate between a benign (e.g. cyst) or
malignant lesion.
3
2
Computed tomography and
magnetic resonance imaging
Nowadays, cross-sectional imaging CT and MRI
are the most commonly used modalities for
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41