topic is related to liver diseases

1. Collateral Pathways in Portal
Hypertension
DrABDULSAMAD P

2. • Presence of portosystemic collateral veins
(PSCV) is common in portal hypertension due to
cirrhosis.
• Physiologically, normal portosystemic
anastomoses exist which exhibit hepatofugal
flow.
• With the development of portal hypertension,
transmission of backpressure leads to increased
flow in these patent normal portosystemic
anastomoses.
• In extrahepatic portal vein obstruction collateral
circulation develops in a hepatopetal direction
and portoportal pathways are frequently found.
• The objective is to illustrate the various PSCV

3. • When blood flow through a vessel or a vascular
bed is obstructed due to occlusion, as in EHPVO,
or distortion, as in liver cirrhosis
• Collateral pathways open up as blood bypasses
the occlusion or obstruction
• Always flowing down a pressure gradient from a
high pressure to a low-pressure vessel or bed.
• The formation of portosystemic pathways occurs
due to reopening of collapsed embryonic
channels or reversal of the flow within existing
adult veins.

5. • The left gastric vein (LGV) anastomoses with the
esophageal veins, which in turn drain into the
azygos vein (AV).
• The superior rectal vein (SRV) anastomoses with
the middle and inferior rectal veins (IRV), which are,
respectively, tributaries of the internal iliac and the
pudendal veins.
• The paraumbilical vein (PUV) anastomoses with
subcutaneous veins in the anterior abdominal wall.
NORMAL PORTOSYSTEMIC ANASTOMOSE

6. • In the retroperitoneal region, tributaries of the
splenic and pancreatic veins anastomose with the
left renal vein.
• Short veins also connect the splenic and colic veins
to the lumbar veins of the posterior abdominalwall.
• The veins of the bare area of the liver also
communicate with those of the diaphragm, as well
as the right internal thoracic vein.

7. NORMALPORTOSYSTEMIC
ANASTOMOSES
ESOPHAGEAL
VEIN
MIDDLE&
INFERIOR
RECTALVEIN
PUDENDAL
VEIN
INTERNAL
ILIACVEIN
PARAUMBLICAL
VEIN
ANTERIOPR
ABDOMINALWALL
Left gastric
vein(LGV)_
Azygous
vein(AV)
SUPERIOR
RECTAL VEIN

8. bare area of the
liver
diaphragm, aswell
asthe right internal
thoracic vein
Tributaries of the
splenic and
pancreatic veins
left
renal vein

9. THE DIRECTION OF COLLATERAL FLO
• When vascular obstruction is intrahepatic,
collateral vessels drain away from the liver
(hepatofugal collateral circulation).
• When the obstruction is extrahepatic, the
collateral circulation usually develops toward the
portal vein beyond the site of obstruction and thus
drains toward the liver
(hepatopetal collateral circulation).

10. • There are intraepithelial channels, a superficial
venous plexus and deep submucosal and
adventitial veins.
• In addition, perforating veins connect the
adventitial and deep submucosal veins.
• Backpressure transmitted through the tributaries
of the portal vein results in the engorgement of
the collaterals outside the gut wall in a
paraesophageal, para-gastric para-rectal or
paracholedochal location.
• The backwaters of the gut wall results in the
formation of varices in a submucosal or subepithelial
location.
ORDER OF APPEARANCE OF COLLAT

11. • In patients with oesophageal varices dilated deep
intrinsic veins displace the superficial venous
plexus, assume a subepithelial position.
• And are easily seen on endoscopy as the red
color sign on varices i.e. telangiectasiae, cherry
red spots, hemocystic spots and red wale
markings or as the varices themselves.
• Veins on the mucosal aspect can cause gastrointestinal
luminal bleeding and those outside the wall may cause
extraluminal i.e. pleural or peritoneal bleeding.
• Submucous veins are the first sites of ‘bloodlogging’
and become varicose before those upon the outer
surface of esophagus in portal hypertension.

12. The varices
outside the
wall are called
para-in location
and varices
adjacent to the
muscular layer are
called peri-in
location.
The hematocystic
spots represent focal
weakness on the
varicea lwall.

13. CLASSIFICATIONOFCOLLATERAL
PATHWAYS
• Simplest classification of PSCVputs
esophagogastric varices into one group andall
other varices asectopic varices.
• Someauthors describe PSCVaccording to
their drainage into either the superior vena
cava(SVC)or the inferior vena cava(IVC)

14. CollateralVesselsDraininginto the SuperiorVenaCava
• left gastricveinlarger than 5–6 mm in diameter at
Doppler ultrasonography is considered abnormal and is
an indicator of portal hypertension
• Shortgastricveinscourse along the lateral aspect of the
gastric wall and descendalong the medial aspectof the
spleen . These veins drain the gastric fundus and the left
side of the greater curvature .
• Dilated short gastric veins appear asacomplextangle of
vessels in theregion ofthesplenichilum
• EsophagealandParaesophagealVarices-Thesevarices are
supplied primarily by the left gastric vein , which divides
into anterior and posterior branches. Theanterior
branch supplies the esophagealvarices,and the
posterior branch forms the paraesophagealvarices.

15. CollateralVesselsDrainingintotheIVC
• Splenorenal and Gastrorenal Shunts- The splenoportal
vein axis and the left renal vein communicate through
the coronary vein, short gastric vein (gastrorenal shunt),
or other veins that normally drain into the splenic vein
(splenorenal shunt)
• Splenorenal or gastrorenal shunts are seen aslarge,
tortuous veins in the region of the splenic and left renal
hila and drain into an enlarged left renal vein.
• Paraumbilical Veinand Abdominal Wall Veins-The umbilical
vein never opens after closure . Rather, patent portal veins
in the ligamentum teres and falciform ligament are actually
enlarged paraumbilical veins.

16. • Paraumbilical vessels may anastomose with the superior
epigastric or internal thoracic veins and drain into the
superior vena.
• Mesenteric collateral vesselsusually appear asdilated and
tortuous branches of the superior mesenteric veinwithin
the mesenteric fat.
• Mesenteric collateral vessels may arise from the superior
and inferior mesenteric veins and may ultimately drain
into the systemic venous system via the retroperitoneal
or pelvic veins .

17. • Aretroperitoneal shunt maybepresent between the
mesenteric vesselsandthe renal vein or inferior venacava.
• Retroperitoneal varicesinclude various pathways between
the intestinal or retroperitoneal tributaries of the superior
or inferior mesenteric veinsandsystemicveins.
• Their communications with the inferior venacavaareknown
as the veinsof Retzius.

18. ESOPHAGEAL VARICES
• VenousDrainageof Esophagus
• eightto ten veins,whichdrainfrom right border of
esophagusto join the medialaspectof AV
• veinson left sideof esophagusdraininto
hemiazygosveins.

19. venousdrainageof abdominal esophagus
• predominantlyto the left gastricvein (LGV)atributary of
the portal venoussystem
• LGVhastwo branches- Theanterior branch of LGVdrains
the cardiacregion andthe posterior branch terminates
by joining the AV
.
• Paraesophagealveinsarepresent on the sideof
esophagus andareconnected with the posterior branch
of the LGV
.

20. • TheAfferent to EsophagealVarices
• LGVisthe afferent to esophagealvarices(EV)
• TheEfferentfromEsophagealVarices
• In 78%of cases,the LGVconnectsto the AVesophagealand
para-esophagealvarices.

22. • VenousDrainageof Stomach
• Gastric varices (GV) are generally defined as cardiac or
fundic according to their location. This location is
consistent with the boundary line of portosystemic
shunting.
• Thisareaof shunting ismainly in posteriorwall of the cardiac
or the fundic area, which isfixed to the retroperitoneum
and isthe closest site to the systemiccirculation.
• Isolated GVare related to gastroepiploic (GEV)veinsand
are located in bodyofstomach
GASTRIC VARICES

23. • Stomachdrainseither directly orindirectlyintothe portalvein
asfollows
• Short gastric veinsdrain from the fundus to the splenic vein
• Left gastroepiploic vein (LGEV)movesalong greater
curvature to splenic vein
• Rightgastroepiploic (RGEV)movesfrom the right end of
greater curvature to superior mesentericvein
• Left gastric vein movesfrom the lessercurvature of the
stomach to the portalvein
• Rightgastric vein movesfrom the lessercurvature ofthe
stomach to the portalvein

24. portal and systemic venous
pathways that are potentially
involved in gastric varices.ADV
=adrenal vein, AZV=azygos
vein, EV=esophageal vein,
HAZV=hemiazygos vein, ICV=
intercostal vein, ITV=internal
thoracic vein, LGV=left gastric
vein, LIPV=left IPV,LRV=left
renal vein, PGV=posterior
gastric vein, PPV=
pericardiophrenic vein, RIPV=
right IPV,SGV=short gastric
vein, 1 =precaval interphrenic
anastomotic vein, 2 =
anastomotic vein to the renal
capsular vein and adrenal vein,
3 =paravertebral anastomotic
veins, * =termination of the
LIPVinto the inferior venacava
(IVC),* =termination of the
LIPVinto the left renalvein.

25. Afferents to GastricVarices
• leftgastric vein - Thesecardiac varices are
contiguous with submucosal varices of thelower
part of theesophagus
• short gastric veins - course along the greater
curvature on the medial side of the spleen to
empty into the splenicvein
• posterior gastric vein - localized between theleft
and short gastric veins, which runs superiorly in
the retroperitoneum and gastrophrenicligament
and joins GV

26. Efferents from GastricVarices
• Gastric varices drain into the systemic vein via the esophageal-
paraesophageal varices (gastroesophageal venous system), the
inferior phrenic vein (IPV) (gastrophrenic venous system).
• The left IPVterminates either (a) inferiorly into the left renal
vein (forming a gastrorenal shunt)
• Majority of GVform the gastrorenal shunt (80–85% ofcases)
while 10–15% form the gastrocaval shunt.

27. • The gastrorenal shuntis formed mainly by lower branch of
inferior phrenic vein, which can open into the renal vein
directly (spleno-gastro-phreno-renal shunt) or via left
adrenal vein.

28. Afferents to gastric
varices. Theafferents to
GVcome from left
gastric vein, shortgastric
veins and posterior gastric
vein the left gastric
vein mainly contributes to
formation of cardiac
varices whereas the short
gastric vein and posterior
gastric vein contribute to
formation of fundal
varices. Isolated gastric
varices are more likely to
be related to
gastroepiploeic
veins

29. • GOVsdraining via the
gastroesophagealvenous
system.Thegastric varices
(GV)aresupplied bythe
left gastric vein (LGV)and
drain via the esophageal
varices(EV) andazygosand
hemiazygosveins (AZV and
HAZV)into the superior
venacava(SVC). Redline
with arrowheads
=blood flow from theleft
gastric vein through the
gastroesophagealvarices
into the azygosvein

30. • IGVsdraining viathe
gastrophrenic venous
system.Gastric varices (GV)
aresuppliedbythe
posterior gastric vein (PGV)
andthe short gastric vein
(SGV),which drain viathe IPV
into the left renal vein (LRV)
(forming agastrorenal shunt
[GRS])or IVC(gastrocaval
shunt [GCS]).Redlines with
arrowheads =blood flow
from the posterior and
short gastric veins through
the gastric varicesinto the
gastrorenaland gastrocaval
shunts.PPV
=pericardiophrenic
vein.

31. enlarged
paraesophageal
varix (arrows)
that
communicates
with the portal
vein through a
dilated left
gastric vein
dilated left gastric vein (arrow)
between the anterior wall of the
stomach and the posterior surfaceof
the left hepaticlobe

32. contrast- enhanced CTimage shows gastric
varices (GV) draining through the multiple
channels of agastrorenal shunt (arrows) into
the left renalvein
Coronal contrast-enhanced CTimage
shows the varices (arrows) draining
through agastrorenal shunt (arrowheads)
into the left renal vein(LRV).

33. PericardiophrenicVein
• Theleft pericardiophrenic vein anastomoseswith the
left IPVat the cardiacapex.
• It runs superiorly alongthe pericardium andin the left
superior mediastinum, then terminates into the left
brachiocephalic vein.
• Theleft pericardiophrenic vein isoften seenwith a
gastrorenalshunt at multidetector CTasanaccessory
drainageveinfrom gastric varices.
• In afew cases(5%),it canserveasa main drainageroute of
gastricvarices

34. Gastric varices with accessory drainage via the
pericardiophrenic vein in apatient with liver
cirrhosis. Coronal contrast-enhanced MIP CTimage
shows gastric varices (GV)draining via a
gastrorenal shunt (black arrows) and the
pericardiophrenic vein (white arrows). LRV=left
renalvein.
Coronal contrast-enhanced CTimage
shows gastric varices (GV) draining mainly
via the leftIPV (arrowheads) and the
pericardiophrenic vein (arrows) into the
left innominatevein.

35. • VenousDrainageof Duodenum
• Four small pancreatico duodenal veins drain the head ofthe
pancreasand the adjacent secondand third portions of the
duodenum.
• Thefour veins regularly form ananterior and sometimes a
posterior arcade through anastomosesbetween the superior
and inferior veins.
• Thepancreatico duodenal veins joins SMV.
• Thetwo major tributaries of the SMVare the gastrocolic
trunk and the first jejunal trunk which join the SMVroughly
at the samelevel but on opposite sides.
ECTOPIC VARICES IN DUODENUM

36. Afferents to DuodenalVarices
• pancreatico duodenal venous arcades,which
are in communication with portal venous
system.

37. Efferentsfrom DuodenalVarices
• Theefferents from DV
• In cirrhosis, they areformed in the descending or transverse
parts of the duodenum and flow hepatofugallyvia
retroperitoneal shunts (alsocalled veinsof Retzius)into the IVC
via the following veins:
1.Rightrenal vein (mesenterorenalshunt)
2.Lumbarveins

38. Portoportal Efferents of Duodenal
Varices
• In extrahepatic portal veinobstruction
(EHPVO)
• Efferents of DVare formed in the
duodenal bulbwhich flow
hepatopetally via portoportal
collaterals into theliver

39. • Venous drainage of duodenum
and afferents to duodenal varices

40. paraumbilical vein (solid arrows) as it extends superiorly and inferiorly to
the anterior abdominal wall to anastomose with the superior and inferior
epigastric veins

41. Retroperitoneal shunt. (a) AxialCT
scanshows tortuous dilated
vessels(arrows) in the medial
portion of theleft
kidney. (b) Coronal MIP CT
portal venogram demonstrates
atortuous, dilated
retroperitoneal shunt (arrows)
that communicates with the
inferior vena cava(I) through
the left renal vein(R).

42. VenousDrainageof JejunoilealVarices
• Mesenteric collateral vesselsmayarise from the superior
(SMV)and inferior mesenteric veins (IMV) ultimately drain
into the IVCvia the retroperitonealor pelvic veins
• Veinsof Retziusare various veins in the dorsal wall of the
abdomen forming anastomoses between the inferior vena
cavaand the superior and inferior mesenteric veins.
• Suchanastomoses between the portal and the systemic
venous systemcanexist even under normal conditions.
ECTOPIC VARICES IN SMALL INTESTIN

43. Afferentsto JejunalandIleal Varices
• Jejunal and ileal veins (tributaries of SMV).
EfferentsfromJejunalandIleal Varices
• Small bowel varices generally drain into abdominal
wall. Theymay also drain into veins of Retzius

44. Applied Anatomyof ColonicandRectalVarices
• Colonicvarices,areusually located in the cecum,and
rectosigmoid region. Theyareoften associatedwith
cirrhosis or portal veinobstruction.
• Lesscommoncausesof colonic varicesarecongestiveheart
failure, mesenteric vein thrombosis, pancreatitis with
splenic vein thrombosis, adhesionsandmesenteric vein
compression
• Theright colon isdrained by three tributaries of SMV,
which include the ileocolic, right colic andmiddle colic
veins. Tributaries joining inferior mesenteric vein drainthe
rest of thecolon
ECTOPIC VARICES IN LARGE INTESTIN

45. Afferentsto ColonicVarices
1.Ileocolic vein
2.Right colic vein
3.Middle colic vein
4.Sigmoid colonic vein
Efferentsfrom Colonic Varices
Efferents candrain into veins of Retzius, whichinclude:
1.Right gonadalvein
2.Right renal vein
3.Systemiclumbar veins
Rectal Varices
Afferents to RectalVarices
Inferior mesenteric vein (IMV) continues asthe superior
rectal vein and acts as afferent to rectalvarices

47. • Theblood from superior rectal vein goesto extrinsic rectal
venous plexus (ERVP),which lies outside rectum below the
level of peritoneal reflection.
• From the ERVPthe blood flows by perforators through the
muscularis propria into intrinsic rectal venous plexus (IRVP)
which consists of two groups of veins – the superior group
lying in the rectal submucosaand the inferior group lying in
the corresponding anal subcutaneous tissue.
• The rectal varices are formed from this superior group of
upper submucosal veins of IRVP
.
• Theinferior group of IRVPlying in the anal subcutaneous
tissue passesdown to form the inferior rectal vein and
contribute to formation of externalhaemorrhoids.

48. Efferents from RectalVarices
Fromboth ERVPandIRVPthe portal hemorrhoidal blood worksinto systemiccirculation
through two portosystemicshunts (recto genital andinter-rectal).
1.rectal venousplexuswith vesico-prostatic or vaginalvenousplexus
2.Theinter-rectal communicationsoccurbetween the three rectal
veins both in ERVPandIRVP

49. Afferents to OmentalVarices
1. Superior or inferior mesentericveins
Efferentsfrom Omental Varices
1. Theretroperitoneal or pelvicveins.
2. Omental veins may also drain into GEV
.
ECTOPIC VARICES: OMENTAL
COLLATERAL VESSELS

50. • In 1883, Sappeydescribed accessoryportal veins entering
the livercapsule from different locations.
• Thesevesselsplay arole in the origin of transhepatic
portosystemic shunts and are sometimes the only PSCV
capableof transporting portal blood into the liver in
EHPVO.
ECTOPIC VARICES: VEINS OF SAPPEY

51. • Thedifferent locationsare:
1.Upper part of falciform ligament -superior veins of Sappey,
2.Lowerpart of falciform ligament–inferior veins of Sappey
3.Ligamentumteres in the central part of falciform
ligament-the recanalized umbilical vein
4.Left triangular ligament–left inferior phrenic vein and
intercostalvein
5.Right triangular ligament–right inferior phrenicvein
6.Gastrohepatic omentum (cystic veins and branches of left
gastric veins)
7.Diaphragmatic veins (bare area of liver)
8.Ligamentum venosum–patent ductus venosusif present

52. • Theparaumbilical veinsarealsocalledinferior veinsof
Sappey.
• Theyaccompanyligamentum teres (obliterated left
umbilical vein) in the falciform ligament andconnect
superior andinferior epigastricveins in the rectus
sheathat umbilicus with left branch of portal vein
• Afferentto UmbilicalVarices
• Left branch of portal vein receivesthe umbilical and
paraumbilical veinsto form umbilical varicesby the
recanalisedligamentum teres in the falciform
ligament.

53. • EfferentsfromUmbilicalVarices
• Superior and inferior epigastric veinsare the
efferents of umbilical varices.
• Themost common path of drainage of
paraumbilical veins isthrough the inferior
epigastricveins, which follow the posterior faceof
the rectus abdominis musclesto finally reachthe
external iliac veins.
• Paraumbilical vesselsmayalsoanastomosewith
internal thoracic veinsand drain into the superior
venacava.

54. • Vesicalvarices are rare in patients withportal
hypertension becausethe bladder wall is an
unusual collateral route for the venous
splanchnic blood. Generally reported casesof
vesical varices haveahistory of abdominal
surgery.
ECTOPIC VARICES: VESICAL VARIC

55. • VenousDrainageof Vaginaand Uterus
• Theanatomyof the vaginaand uterus makesthem unlikely
locations to develop varicesasthe uterus hasanextensive
extensive venousplexus,which primarily drains into the
uterine veinsand later into the internal iliac vein (part of
systemic circulation).
• Thevaginaalsohasavenous plexus,which similarly drains
into the internal iliac vein via bilateral vaginal veins.
• The plexusesare in communication with eachother and
with thevesical and hemorrhoidal plexuses.
ECTOPIC VARICES: VAGINAL AND UTERINE
VARICES

56. Afferentto VaginalandUterine Varices
• Superior portion of the hemorrhoidalplexus
EfferentfromVaginalandUterine Varices
• Venousplexusesof uterus and vagina,internal iliac vein and
uterine veins.

57. • Gallbladder varicesarepresent in 12%of patientswith
portal hypertension but aremore frequent in those with
extrahepatic portal hypertension(30%).
• TheGBwall varicesrefer to presenceof varicesin or
outside the wall of GBin apericholecysticlocation.
• Afferentsto GallbladderVarices
• Cysticvein, branch of the right portalvein.
• EfferentsfromGallbladder Varices
• Theymaydrain to hepatic vein
ECTOPIC VARICES: GALLBLADDER VARI

58. • These collateral veins are related to 2 preformed venous
systems near the extrahepatic bile ducts: the paracholedochal
(PACD) veins of Petren, and the epicholedochal (ECD) venous
plexusof Saint.
• The PACDvenous plexus of Petren runs parallel to the CBD, and
the ECD plexus of Saint veins form a reticular mesh on the
surfaceof the CBD.
• The PACD collaterals, if dilated, may cause extrinsic
compression and protrusion into the thin and pliable CBD.
• And the ECD collaterals, if dilated, may make the normally
smooth intraluminal surface of theCBDirregular.
ECTOPIC VARICES: BILIARY VARICES

59. • Saint's anatomic studies suggestthat dilatation of the
PACDveinswill occurfirst in portal hypertension.
• PortoportalConnectionsof BiliaryVarices
• Theright-sided plexus cancommunicate with
pancreatico duodenal vein to the cystic vein.
• The left sided plexus can communicate with left and
right gastric vein (LGV and RGV) and with the left portal
vein (LPV).
• Generally the flow occurs toward the branches of portal
vein in the liver.

60. •

61. • Surgeryinvolving apposition of abdominal structures
(drained bysystemic veins) to the bowel (drained by portal
tributaries) mayresult in the formation of collaterals at
unusualsites.
• Transcapsularcollaterals are especially common in
patients whohad undergone hepatobiliary surgery and
who had chronicPVT.
• 50%of patients with surgical digestive stoma in acontext
of portal hypertension havestomal varices.
ECTOPIC VARICES: ANASTOMOTIC AND
STOMAL VARICES

62. • VenousDrainageof Diaphragm
• Superior surface of diaphragm isdrained by pericardiophrenic
and musculophrenic veins, which drain into the internal
thoracic vein.
• Inferior phrenic veinsdrain the inferior surface.
• Theright inferior phrenic vein usually opensinto the inferior
venacavawhereasthe left inferior phrenic vein joins the IVC
and or left renal or suprarenal vein.
• Cardiophrenic varicesparticularly on the right side are usually
located at acardiophrenic angle, and rupture israre.
ECTOPIC VARICES: DIAPHRAGM

63. • Afferentto DiaphragmaticVarices
• Cardiophrenic varices.
• EfferentsfromDiaphragmatic Varices
• Internal mammaryvein.

64. • Theword interportal communication isdifferent from
portoportal communications.
• Theconceptual difference between portoportal and
interportal collateral isthat aportoportalcollateral will be
connectedto the portalveinonentryand/or exit .
• Whereas an interportal collateral goesfromonepart of
portalvenoussystem intoanother part of portal venous
system.
INTERPORTAL COMMUNICATIONS

65. • Interportal communication indicates flow of blood that
bypassesan obstructedsegmentof the portalvenous
system.
• Thisoccurs mainly in EHPVOwhere the collaterals havea
tendency to go toward the portal venoussystemafter
bypassing the site of obstruction.

66. COLLATERAL PATHWAYS IN BUDD–CHIARI
SYNDROME
• Three types of obstruction can occur in Budd–Chiari
syndrome(BCS) which include
• obstruction to the major hepatic veins alone (Type I)
• obstruction to the suprahepatic IVC alone (Type II)
• and combined obstruction to the major hepatic veins
and IVC (Type III)
• Development of collateral pathways depends on the
type and location of obstruction in BCS and can occur
in intra and extrahepatic locations.

67. •Twoforms of intrahepatic collaterals maydevelop:
1.Those that communicate withsystemicveinsviathe
subcapsularvessels–
• Thesubcapsularvesselsoriginate asintrahepatic collaterals
but becomeextrahepatic after goingthrough the capsule
of liver and communicatewith leftinferior phrenic vein.
2. Those that shunt blood from the occludedto the non-
occludedsegmentsof the hepatic vein.
• Intrahepatic collaterals, which remain inside liver, develop
as commashapedcollateralsbetween the adjacentright
andleft hepaticvein.

68. REFERENCES
1.Collateral Pathways in Portal Hypertension
Malay Sharma et al.,*, Chittapuram S. Rameshbabu**