Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_718_Библиотеки_им_академика_М_И_Перельмана
.pdf
Fig.91: Normal anatomy vs anatomical variations of the gall bladder. Source [91].
Anatomical variants of the gallbladder:
Duplication, with or without a double cystic duct.
Agenesis;
Internal septation;
Ectopic location (most commonly left-sided);
Fig.92: Anatomical variants of the gallbladder. Source [92].
80
Intrahepatic biliary tree:
1. The left hepatic duct is formed by the union of segment II, III and IV ducts, most often
behind or to the left of the umbilical portion of the left portal vein.
2. The right hepatic duct is formed by the union of the right anterior (medial) and posterior
(lateral) sectoral ducts.
A. The right anterior (medial) sectoral bile duct drains segments V and VIII, and the right
posterior (lateral) sectoral duct drains segments VI and VII.
B. The right posterior sectoral duct usually curves around the posterior aspect of the right
anterior duct before fusing with its medial aspect; this is known as Hjortsjö’s crook and is
an important technical consideration when performing liver resection.
N.B.: The bile ducts draining the caudate lobe (segment I) usually join the origin of the left hepatic
duct or may drain into both hepatic ducts near the hilar confluence.
Fig.93: Intrahepatic biliary tree. Source [93].
Extrahepatic biliary tree:
1.The cystic duct; 2- 4cm long and has a luminal diameter of 2–3mm.
It passes posteriorly and medially from the neck of the gallbladder, often in a tortuous fashion, to
unite with the common hepatic duct and form the common bile duct.
Anatomical variations of the cystic duct:
1.Low insertion into CBD.
2.Absent cystic duct.
3.Insertion onto the right hepatic duct.
4.Insertion to the biliary confluence.
5.May drain into the distal common bile duct or into a more proximal duct such as the proximal
common hepatic duct or right hepatic duct instead of joining the middle third of the combined
lengths of the common hepatic and common bile ducts.
81
6.May join the medial, anterior or posterior aspect of the common bile duct instead of lateral
aspect.
7.May go spirally around the common bile duct or run parallel to it in the free edge of the lesser
omentum instead of forming an oblique angle with the common bile duct.
8.Rarely, the cystic duct is double or absent, or receives an anomalous hepatic duct from segment
V of the liver.
These variations in cystic duct anatomy are of considerable importance during cholecystectomy.
Fig.94: Anatomical variations of the cystic duct. Source [94].
2.Hepatic ducts:
The right and left hepatic ducts emerge from the liver and unite near the right end of the porta
hepatis to form the common hepatic duct (CBD). The extrahepatic right duct is short (0.5–2.0cm
in adults) and nearly vertical, while the left is longer (1.5–3.5cm) and more horizontal, and lies
along the inferior border of segment IV.
The CBD descends approximately 3cm before being joined obliquely on its right by the cystic duct
to form the common bile duct.
The common hepatic duct lies to the right of the hepatic artery and anterior to the portal vein in
the free edge of the lesser omentum. The luminal diameter of the normal CBD is less than 5mm.
3.The common bile duct (CBD):
The common bile duct is formed near the porta hepatis, by the junction of the cystic and common
hepatic ducts (6-8cm long and its luminal diameter is no more than 7mm).
The common bile duct can be divided into:
1.The supraduodenal segment; descends posteriorly, anterior to the epiploic foramen and inferior
vena cava, in the free right border of the lesser omentum, where it lies anterior and to the right of
the portal vein and to the right of the hepatic artery.
82
2.The retroduodenal segment; lies behind the first part of the duodenum with the gastroduodenal
artery on its left.
3.The pancreatic segment; runs in a groove on the posterior surface of the head of the pancreas,
embedded in the gland to a variable degree; it lies up to 2cm away from the medial wall of the
second part of the duodenum and anterior to the right renal vein.
Hepatopancreatic ampulla:
The CBD descends behind the head of the pancreas medial to the second part of the duodenum,
approaching the right end of the pancreatic duct. The two ducts usually enter the duodenal wall
together in a Y configuration to form a short common channel measuring between 2 and 10mm in
length.
This common channel often contains a dilation known as the hepatopancreatic ampulla of Vater
and it opens via a single orifice on to the medial wall of the second part of the duodenum at the
major duodenal papilla.
Fig.95: Ampulla of Vater. Source [95].
Hepatobiliary triangle:
The triangular region formed between the cystic duct, the common hepatic duct and the inferior
surface of the liver is the hepatobiliary triangle, which is often mistakenly referred to as Calot’s
triangle, which is an isosceles triangle based on the common hepatic duct, with the cystic artery
and cystic duct forming its sides.
The hepatobiliary triangle is bridged by the double layer of peritoneum that forms the short and
variable mesentery of the cystic duct. Between these two layers there is a variable amount of fatty
connective tissue, lymphatics, the cystic lymph node, autonomic nerves, and usually the cystic
artery as it runs from the right hepatic artery to the gallbladder; occasionally, there may also be an
accessory bile duct.
83
Fig.96: Hepatobiliary triangle (Above in blue) and Calot’s triangle (Below in yellow). Source [96].
Blood supply:
A) Arterial supply:
1.The cystic artery (less than 3mm in diameter)
Origin:
From the right branch of the hepatic artery, most commonly from the hepatic artery proper.
Rarely, it may arise from the left hepatic, gastroduodenal, superior pancreaticoduodenal, coeliac,
right gastric or superior mesenteric arteries;
Course:
Passes posterior to the common hepatic duct within the hepatobiliary triangle, where it lies superior
to the cystic duct.
Branches:
On reaching the superior aspect of the neck of the gallbladder, it divides into a superficial branch
that runs along the inferior surface of the gallbladder, and a deep branch that runs between the
gallbladder and its fossa; the branches anastomose over the surface of the body and fundus.
The cystic artery also gives rise to multiple fine branches that contribute to the blood supply of the
extrahepatic bile ducts.
2.Ductal arteries:
A) The common bile duct is frequently supplied by 2–4 small-caliber arteries that form a long,
tortuous, anastomotic network along its length, which originates from the hepatic artery above,
branches from the posterior superior pancreaticoduodenal artery, the retroduodenal artery (both of
which originate from the gastroduodenal artery and cross anterior to retroduodenal segment of the
bile duct) and a retroportal artery (arising from the superior mesenteric artery or coeliac trunk)
from below.
B) The supraduodenal segment of the bile duct is supplied by a fine network of periductal arteries
that arise from the right and left branches of the hepatic artery and form an anastomotic plexus
within the connective tissue of the hilar plate.
84
C)The intrahepatic ducts are supplied by segmental branches of the hepatic artery arising within
the Glissonian sheaths.
3.Small arterial branches; from the parenchyma of segment IV or V of the liver may contribute
to the supply of the body of the gallbladder, particularly when it is substantially intrahepatic.
Fig.97: Blood supply of the GB. Source [97].
B) Venous drainage:
Cystic veins:
Arising from the superior surface of the body and neck of the gall bladder lie in areolar tissue
between the gallbladder and liver, and drain into segmental portal veins within the liver.
The remainder of the organ drains by one or two small cystic veins into either portal vein branches
within the liver or portal venous tributaries draining the hepatic ducts and upper bile duct.
Lymphatic drainage:
A) Lymph from the gallbladder and cystic duct:
1.To the cystic node, which usually lies above the cystic duct in the hepatobiliary triangle, and
from here via nodes in the free edge of the lesser omentum and along the common hepatic artery
to coeliac lymph nodes.
2.Via lymphatics that descend along the common bile duct to the superior
retropancreaticoduodenal node.
3.Directly to superior mesenteric nodes.
B) Lymphatics on the hepatic aspect of the gallbladder: directly to intrahepatic lymph vessels.
C)Lymphatic vessels accompanying the hepatic ducts and upper bile duct:
To hepatic nodes at the porta hepatis and then via lymph nodes in the free edge of the lesser
omentum to coeliac nodes.
D) Lymphatics from the lower common bile duct:
1.To hepatic nodes at the porta hepatis and then via lymph nodes in the free edge of the lesser
omentum to coeliac nodes.
2.Directly to retropancreatic and superior mesenteric nodes.
85
Innervation:
A) The gall bladder:
1.Gallbladder contraction occurs in response to cholecystokinin (CCK) and parasympathetic
(vagal) stimulation.
2.Postganglionic sympathetic nerve fibers from the coeliac and superior mesenteric ganglia are
inhibitory to gallbladder smooth muscle.
3.Sympathetic afferents from the gallbladder convey pain sensation; they travel with the greater
and lesser splanchnic nerves and have their cell bodies in the T7–9 spinal cord segments.
B) The CBD and smooth muscle of the hepatopancreatic ampulla:
Vagus nerve, either directly or via the hepatic plexus, and by sympathetic nerves.
Peritoneal coverings: The gall bladder is a Mesoperitoneal organ.
¾ Rarely;
1. Intraperitoneal.
2. Extraperitoneal (Intrahepatic).
Holotopy:
The gall bladder is projected into the Proper Epigastric Region.
The fundus of the gall bladder projects to:
The anterior border of the ALAW where the external border of the rectus muscle and costal arch
cross at the level where the right IX-X costal cartilages accrete. (Right Parasternal line).
OR could be described as the point at which the costal arch is crossed by the line connecting the
apex of the right axillary fossa with the umbilicus.
Syntopy:
1.Superiorlly & anteriorly; The liver.
2. To the right of the fundus; Right (hepatic) colic flexure & first part of the duodenum.
3. To the left; The gastric pylorus.
4. If the liver is low positioned e.g., hepatomegaly; Small intestinal loops.
Fig.98: Syntopy of the gall bladder. Source [98].
Skeletopy:
The gall bladder projects to the 9th costal margin, at the intersection of the lateral border of the
right rectus abdominis and the costal cartilage.
86
3) The stomach:
Parts of the stomach:
1.The fundus; is dome-shaped and projects above and to the left of the Oesophageal opening
(cardiac orifice) to lie in contact with the left dome of the diaphragm; it lies above a horizontal
line from the cardiac notch to the greater curvature.
2.The body; extends from the fundus to the angular incisure (incisura angularis), a constant
external notch at the lower end of the lesser curvature.
3.The cardia; adjacent to the Oesophageal opening. A line drawn from the angular incisure to an
inconstant indentation on the greater curvature defines the lower boundary of the body.
4.The pyloric antrum; extends from previously mentioned line to where the stomach narrows to
become the pyloric canal (1–2 cm long), which terminates at the pyloric orifice.
Gastric curvature:
1.The lesser curvature; extends between the cardiac and pyloric orifices and forms the medial
border of the stomach. It descends from the medial side of the esophagus in front of the decussating
fibres of the right crus of the diaphragm, curves downwards and to the right, and lies anterior to
the superior border of the pancreas. It ends at the pylorus, just to the right of the midline. In the
most dependent part, there is typically a notch, the angular incisure.
2.The greater curvature; It starts from the cardiac notch, formed between the lateral border of
the abdominal esophagus and the fundus of the stomach, and arches upwards, posterolaterally and
to the left. Its highest convexity, the apex of the fundus, at the level of left 6
Th
rib, from this point,
it sweeps inferiorly and anteriorly, slightly convex to the left, almost as far as the 10TH costal
cartilage, where it turns medially to end at the pylorus in the transpyloric plane L1.
Fig.99: Parts of the stomach. Source [99].
87
Gastric surfaces:
1.Anterior (superior) surface;
A) The lateral part of the anterior surface; lies posterior to the left costal margin in contact with
the diaphragm, which separates it from the left pleura, the base of the left lung, the pericardium
and the left seventh to ninth ribs and costal cartilages. Posterior to the costal attachments of the
upper fibres of transversus abdominis.
B) The upper left part of the anterior surface; curves posteriorly and lies in contact with the visceral
surface of the spleen.
C)The right half of the anterior surface; is related superiorly to the left lobe of the liver and
inferiorly to the anterior abdominal wall.
2.Posterior (inferior) surface:
The posterior surface of the stomach lies anterior to the left crus and lower fibres of the diaphragm,
the left suprarenal gland, the superior pole of the left kidney, the splenic artery, spleen, the anterior
surface of the pancreas, and the upper layer of the transverse mesocolon, left colic flexure forming
the stomach bed, which is separated from the stomach by the lesser sac.
Fig.100: The stomach bed. Source [100].
88
Gastric orifices:
1.Cardiac orifice: Located at 35-40 cm from the incisor teeth
The esophagus opens into the stomach at the cardiac orifice, which lies to the left of the midline
behind the 7TH costal cartilage at the level of the T11.
2.Pyloric orifice: Located at 50-52 cm from the incisor teeth
lies 1–2 cm to the right of the midline in the transpyloric plane L1.
The pyloric sphincter is formed by a circumferential thickening of circular muscle interlaced with
connective tissue septa and some longitudinal muscle fibres, and is palpably thicker than the
adjacent stomach and duodenum.
Vascular supply of the stomach:
A) Arterial supply:
1.The left gastric artery:
Origin: The coeliac trunk.
Course: It ascends to the left of the midline and crosses over the lower end of the left crus of the
diaphragm beneath a fold of peritoneum in the upper posterior wall of the lesser sac (the
gastropancreatic fold). It runs forwards into the superior portion of the lesser omentum adjacent to
the upper end of the lesser curvature, and then turns anteroinferiorly to run along the lesser
curvature between the two peritoneal leaves of the lesser omentum.
Branches:
1.Oesophageal branches.
2.Multiple branches that run on to the anterior and posterior surfaces of the stomach.
3. Anastomoses with the right gastric artery in the region of the angular incisure.
2.Short gastric arteries (5-7):
Origin: Splenic artery or from the proximal left gastroepiploic artery.
Course: Pass between the layers of the gastrosplenic ligament.
Branches: Supply the gastric fundus and cardiac orifice.
They anastomose with branches of the left gastric and left gastroepiploic arteries.
3.Left gastroepiploic artery:
Origin: Splenic artery.
Course: It arises near the splenic hilum and runs anteroinferiorly between the layers of the
gastrosplenic ligament into the upper gastrocolic omentum, descends between the layers of
peritoneum close to the greater curvature and often anastomoses with the right gastroepiploic
artery.
Branches: Gastric branches to the fundus and the body of the stomach through the gastrosplenic
and gastrocolic ligaments.
4.Posterior gastric artery:
Origin: Splenic artery.
Course: Ascends behind the peritoneum of the lesser sac towards the fundus to reach the posterior
surface of the stomach.
Branches: Supplies the posterior wall of the upper part of the gastric body.
5.Right gastric artery:
Origin: Hepatic artery proper.
Course: runs forwards into the lesser omentum just above the first part of the duodenum. It then
travels within the lesser omentum along the lesser curvature of the stomach.
Branches: Multiple branches to the anterior and posterior surfaces of the stomach.
Anastomoses with the left gastric artery.
89
Соседние файлы в папке Библиотека им академика М.И. Перельмана