Imaging approach to Pancreas,
Gallbladder and Bile duct anomalies
and anatomical variants
A Reinders
Department of Radiology
March 2012
Introduction
• Embryology & normal anatomy
– Pancreas
– Bile ducts
– Gallbladder
– Cystic duct
– Liver vascular anatomy*
• Congenital variants
• Imaging approach
• Report
Embryology
Bile duct
4th Week of Fetal life
Hepatic ducts
Hepatic
Diverticulum
Gallbladder
Dorsal pancreatic
Outpoutching
Ventral
pancreatic
outpoutching
Primitive Foregut
& midgut
Figure 1a. Drawings illustrate the normal embryologic development of the pancreas and
biliary tree.
Mortelé K J et al. Radiographics 2006;26:715-731
©2006 by Radiological Society of North America
Embryology
7th Week of Fetal life
Dorsal pancreas
Dorsal pancreatic
outpoutching
Posterior pancreatic
ductal system
Pancreas
Extrahepatic BD
Ventral pancreatic
outpouching
Intrahepatic BD
Ventral pancreas
Figure 1c. Drawings illustrate the normal embryologic development of the pancreas and
biliary tree.
Mortelé K J et al. Radiographics 2006;26:715-731
©2006 by Radiological Society of North America
Figure 1d. Drawings illustrate the normal embryologic development of the pancreas and
biliary tree.
Mortelé K J et al. Radiographics 2006;26:715-731
©2006 by Radiological Society of North America
Congenital Variants
• Pancreas
– Annular pancreas
– Hypoplasia/aplasia of the pancreas
– Ducts
• Rudimentary duct of Santorini
• Dominant duct of Santorini
• Ansa Pancreatica
– Pancreas Divisum
– Ectopic pancreas
Annular Pancreas
• Rare = 1:2000
– Incomplete rotation of ventral anlage
• Segment of pancreas encircling 2nd part of
duodenum
– Obstruction 10%
Extramural
Intramural
Ventral pancreatic
duct
Pancreatic tissue
intermingled with
muscle fibres
Encircles
duodenum and
joins MPD
Small ducts drains
directly into
duodenum
Lecco’s theory
Baldwin’s theory
Lee NK, Kim S, Jeon TY et al. Complications of congenital and developmental abnormalities of the gastrointestinal tract in
adolescents and adults: Evaluation with multimodality imaging. Radiographics 2010;30:1489-1507
Annular Pancreas
Annular pancreas in a 55-year-old man
with
repeated episodes of vomiting.
Contrast-enhanced CT
image shows pancreatic tissue
(arrows) completely encircling
the descending portion of the
duodenum (*).
Lee NK, Kim S, Jeon TY et al. Complications of congenital and developmental abnormalities of the gastrointestinal tract in adolescents
and adults: Evaluation with multimodality imaging. Radiographics 2010;30:1489-1507
Annular Pancreas
Mortele KJ, Rocha TC, Streeter JL et al. Multimodality Imaging of Pancreatic and Biliary Congenital Anomalies. Radiographics
2006; 26:715-731
Hypoplasia/Agenesis of Pancreas
• Hypoplasia
– Absence of ventral/dorsal anlage
– Dorsal hypoplasia more common
• NB to rule out pancreatic carcinoma with “upstream”
atrophy of gland
• Degrees of hypoplasia with varying degrees of abscence of
neck, body and tail, MDP and duct of Santorini
• Agenesis
– Total agenesis is rare = incompatible with life
– Associated with other GIT malformations
• Polysplenia
• GB aplasia
Ductal Anatomy
• Two major duct
– Wirschung
• Main = 1.5 – 3.5 mm diameter
• 20 – 30 side branches
• Meets with CBD to pass through SOO8
– Y (75%) or V (20%) configuration – 10 – 15 mm long
– U type (5%)
– Santorini
• Drains anterior and superior portion of head
• Normal narrowing at level of junction between MPD and W
• No proximal dilatation of duct
– Minor duodenal papilla
• +/- 27 different ductal configurations
Figure 3a. Normal pancreatic ductal anatomy.
Mortelé K J et al. Radiographics 2006;26:715-731
©2006 by Radiological Society of North America
Ductal variants
• Rudimentary duct of Santorini (30%)
– Duct of Wirsung as manor drainage route still
• Dominant duct of Santorini (1%)
– Major drainage route
• Ansa Pancreatica
– Duct of Santorini forms a sigmoid curve as it
courses to duct of Wirschung
Figure 6b. Variant pancreatic ductal anatomy – Ansa Pancreatica
Mortelé K J et al. Radiographics 2006;26:715-731
©2006 by Radiological Society of North America
Sphincter of Oddi
• 3 separate smooth muscle layers
– Surrounds MPD and CBD before AOV
• Anomalous junctions
– Fusion of MPD and CBD outside duodenal wall
– = Long common channel (>15mm)
• Reflux
– Pancreatitis
– Cholangitis
• Cyst
• Choledocal web
Figure 3d. Normal pancreatic ductal anatomy.
Mortelé K J et al. Radiographics 2006;26:715-731
©2006 by Radiological Society of North America
Figure 10a. Abnormal common channel.
Mortelé K J et al. Radiographics 2006;26:715-731
©2006 by Radiological Society of North America
Figure 10b. ERCP: Abnormal common channel with CBD web in child
Mortelé K J et al. Radiographics 2006;26:715-731
©2006 by Radiological Society of North America
Pancreas Divisum
• Common 4 – 10%
• Ventral and dorsal ducts DONT fuse
– Wirschung (ventral) = atretic & short
– Santorini (dorsal) = Larger in caliber
• Focal dilatation of terminal portion – Santorinicele
• Cause obstruction at minor papillae of duodenum
Figure 6a. Variant pancreatic ductal anatomy - Santorinicele
Mortelé K J et al. Radiographics 2006;26:715-731
©2006 by Radiological Society of North America
Mortele KJ, Rocha TC, Streeter JL et al. Multimodality Imaging of Pancreatic and Biliary Congenital Anomalies. Radiographics
2006; 26:715-731
Ectopic pancreas
• Incidence – 0,6 – 13%
• 0,5 – 2 cm in largest dimensions
• Usually asx – rarely become malignant
• In submucosa (50%)
– Stomach (26 - 38%)
– Duodenum (28 – 36%)
– Jejenum (16%)
– Meckel’s diverticulum
Biliary System
• Liver segments
– Cuinaud classification
• Main hepatic ducts
• Cystic duct
• Choledochal cyst
– Todani’s classification
• Gallbladder
Biliary System
• Intrahepatic bile ducts (IBD) run parallel to portal
supply
• RHD
– Right posterior duct = I, VI & VII (horizontal)7
• Super and Inferior
– Right anterior duct = V & VIII (vertical)
• Superior and inferior
• LHD
– Draining II, III and IV
• Lateral and medial
– Superior and inferior
• CHD
• 58 % of people
Images available from URL: http://www.pkdiet.com/pages/pld/pldresection.htm
Figure 5. Normal biliary anatomy.
Mortelé K J et al. Radiographics 2006;26:715-731
©2006 by Radiological Society of North America
Biliary System
• Right posterior duct (RHD)
– Drain into LHD before confluence with RAD
• 13 – 19%
– Will not pass RAD posterior but drains directly into it
• 12%
– “Tripple confluence”
• 11%
– Drains into CHD
• Left <1%
• Right 5% - “aberrant hepatic duct”
Biliary System
Onofrio AC, Anandkumar HS, Raul NU et al. Vascular and biliary variants in the liver: Implications for liver surgery. Radiographics
2008; 28:359-378
Biliary System
Cystic duct
• Low insertion
– Into distal 1/3 of CHD (9%)
• Medial insertion
– Left side of CHD (10-17%)
• Parallel coarse with CHD
– 1.5 – 25%
– 2 cm long
• Spiral course
– Anterior
– Posterior
• Into intrahepatic bile duct
– Right (0.3%) and left rarely
• Abscence
– Drains directly into CBD
Figure 6. Anatomic variants in the cystic duct.
Turner M A , Fulcher A S Radiographics 2001;21:3-22
©2001 by Radiological Society of North America
Figure 7b. (7a) Cholangiogram shows a right lateral insertion of the cystic duct (arrows) into
the extrahepatic bile duct.
Turner M A , Fulcher A S Radiographics 2001;21:3-22
©2001 by Radiological Society of North America
Biliary System
• Choledochal cysts
– Rare
– Biliary tree dilatation
– > Female 4:1
•
•
•
•
Abdominal pain
Jaundice
Right upper quadrant mass
Children 2 – 38%
Todani Classification
Images available from URL: http://radiopaedia.org/encyclopaedia/quizzes/all/8097
Figure 16b. Todani Type 1 Choledochal cysts.
Mortelé K J et al. Radiographics 2006;26:715-731
©2006 by Radiological Society of North America
Figure 16d. Todani Type 2 Choledochal cysts.
Mortelé K J et al. Radiographics 2006;26:715-731
©2006 by Radiological Society of North America
Figure 16f. Todani Type 3 Choledochal cyst
Mortelé K J et al. Radiographics 2006;26:715-731
©2006 by Radiological Society of North America
Figure 17b. (a, b) Drawing (a) and coronal MR cholangiopancreatogram (b) show type IV
choledochal cysts.
Mortelé K J et al. Radiographics 2006;26:715-731
©2006 by Radiological Society of North America
Figure 17d. (a, b) Drawing (a) and Endoscopic Retrograde Cholangiopancreatogram (b)
show type IV choledochal cysts.
Mortelé K J et al. Radiographics 2006;26:715-731
©2006 by Radiological Society of North America
Caroli’s Disease
• Imaging
– “Central dot sign”
• Dilagted IHD with contrast enhancement of the portal
branches
• Todani classifications Type 5
– If large IBD affected = Caroli’s disease
– If small interlobular bile ducts also affected =
Congenital hepatic fibrosis
• Caroli’s Syndrome
Gallbladder
• Adjacent to inferior surface of liver
– Plane of interlobar fissure
– Different positions
• Under left lobe
– Situs inversus
• Intrahepatic
– Subcapsular along ant-inf surface of right lobe of liver
• Transverse
• Retroperitoneal
– Congenital
– Acquired
Gallbladder
• GB displacement/rotation
– Hepatic lobe abnormalities
• Aplasia
• Hypoplasia
– Associated with Cystic Fibrosis
• Hypertrophy
• Agenesis
• Duplication
Rare
Gallbladder
• Phrygian cap
– Ancient Greek headgear
– Asx folding of GB fundus
• Junctional fold
– Usually posterior wall
• Septa
– Multiseptate
• Honeycombed appearance
Statis and stone
formation
– Extension of Spiral valves of Heister
• Other
– Duplication/Triplication, Bifid gallbladder
– Diverticulum
Gallbladder
Meilstrup JW. Hopper KD. Thieme GA. Imaging of gallbladder variants. AJR 1991;157:1205-1208
Meilstrup JW. Hopper KD. Thieme GA. Imaging of gallbladder variants. AJR 1991;157:1205-1208
Liver
• Arterial
– Proper hepatic artery (CHA from Coeliac trunk)
• Right, middel and left hepatic artery (55%)
• Porto-venous
– Porta hepatis (SMV and SV)
• Right
– Post and anterior
• Left portal vein
• Venous = IVC
– Right
• Segment 6 & 7
– Middle
• Segments 4,5 & 8
– Left
• Segments 2 & 3
Common trunk (60%)
Arterial and Venous anatomy
Onofrio AC, Anandkumar HS, Raul NU et al. Vascular and biliary variants in the liver: Implications for liver
surgery. Radiographics 2008; 28:359-378
Porto-venous anatomy
Onofrio AC, Anandkumar HS, Raul NU et al. Vascular and biliary variants in the liver: Implications for liver surgery.
Radiographics 2008; 28:359-378
Arterial Variants
Onofrio AC, Anandkumar HS, Raul NU et al. Vascular and biliary variants in the liver: Implications for liver surgery. Radiographics
2008; 28:359-378
Arterial Variants
Onofrio AC, Anandkumar HS, Raul NU et al. Vascular and biliary variants in the liver: Implications for liver surgery.
Radiographics 2008; 28:359-378
Venous Variants
• Tributary veins
– Drain segments in addition to hepatic veins
• Eg. Segment 8 into MHV (9%)
• NB for surgical incision (Cantlie line)
• Accessory inferior right hepatic vein
– Drains directly into IVC (47%)
– NB:
• Nr of acc veins
• Size and distance from main hepatic venous drainage site
along IVC
– Surgical difficulty if >40 mm
Venous Variant
Onofrio AC, Anandkumar HS, Raul NU et al. Vascular and biliary variants in the liver: Implications for liver surgery.
Radiographics 2008; 28:359-378
Portal Vein Variants
Gallego C. Velasco M. Marcuello P et al. Congenital and Acquired anomalies of the portal venous system. Radiographics
2002;22:141-159
Portal Vein Variants
• Variants common (20%)
– Trifurcation (7 – 10%)
– RPPV from MPV (5 – 6%)
– RAPV from LPV (3 – 4%)
• Cantlie line
• Hypovascular surgical line – transplantations
• 1cm to right of MHV
– Between IVC and gallbladder fossa
Imaging
• No surprises – Radiologist/Surgeon
• Pre operative planning
–
–
–
–
Liver transplant/resection/cholecystectomy
Whipple’s procedures
Intra arterial chemotherapy (HAIP)
Asymptomatic
• Several options
– Helical CT Cholangiography, MR Cholangiography
– ERCP, PC Cholangiography
– Oral Cholangiography, Scintigraphy
• Best?
–
Kapoor V, Peterson MS, Baron RL. Intrahepatic biliary anatomy of living adult donors: Correlation of Mangafodipir
Trisodium – enhanced MR Cholangiography and intraoperative cholangiography. AJR Nov 2002; 179(5):1281-1286
Report
• Technique used
– Sequences and contrast material
– Puncture site
• Normal anatomy
– If not – where does what implant?
• Classifications and measurements
• Distinguish from pathological processes
Bibliography
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1. Lee NK, Kim S, Jeon TY et al. Complications of congenital and developmental abnormalities of
the gastrointestinal tract in adolescents and adults: Evaluation with multimodality imaging.
Radiographics 2010;30:1489-1507
2. Mortele KJ, Rocha TC, Streeter JL et al. Multimodality Imaging of Pancreatic and Biliary
Congenital Anomalies. Radiographics 2006; 26:715-731
3. Rizzo RJ, Szucs RA, Turner MA. Congenital abnormalities of the pancreas and biliary tree in
adults. Radiographics 1995;15:49-68
4. Onofrio AC, Anandkumar HS, Raul NU et al. Vascular and biliary variants in the liver: Implications
for liver surgery. Radiographics 2008; 28:359-378
5. Turner MA, Fulcher AS. The Cystic Duct: Normal Anatomy and Disease Processes. Radiographics
2001;21:3-22
6. Kapoor V, Peterson MS, Baron RL. Intrahepatic biliary anatomy of living adult donors: Correlation
of Mangafodipir Trisodium – enhanced MR Cholangiography and intraoperative cholangiography.
AJR Nov 2002; 179(5):1281-1286
7. Applied Radiological anatomy. Butler P, Mitchell AWM, Ellis H Editors. Cambridge University
Press. United Kingdom. 2008. Chapter 9. Embryology of the gastrointestinal tract and its adenxae.
p185-186
8. Radiology Review Manual. 6th Edition. Danhert Wolfgang. Lippincott Williams & Wilkins.
Philadelphia. 2007. p687 - 690
9. Primer of Diagnostic Imaging. 4th Edtion. Weissleder R, Wittenberg J, Mukesh GH, Chen J. Mosby
Elsevier. 2007. p227-228
10. Meilstrup JW. Hopper KD. Thieme GA. Imaging of gallbladder variants. AJR 1991;157:1205-1208
11. Gallego C. Velasco M. Marcuello P et al. Congenital and Acquired anomalies of the portal
venous system. Radiographics 2002;22:141-159