The Normal Liver Part 4: Vasculature Flashcards
(18 cards)
Liver Vasculature
• In the hepatic portal system, the liver receives a dual blood supply from the _____
portal vein and hepatic _____
• The hepatic portal vein carries _____ blood drained from the spleen,
gastrointestinal tract and its associated organs; it supplies approximately _____% of the
liver’s blood.
• The hepatic arteries supply _____ blood to the liver and account for the remainder
of its blood flow
• The hepatic portal system connects the capillaries of the _____ tract with the capillaries in the liver. Nutrient-rich blood leaves the gastrointestinal tract and is first brought to the liver for processing before being sent to the _____
• A portal system is a venous structure that enables blood from one set of capillary beds to drain into another set of capillary beds, without first returning this blood to the _____. The majority of capillaries in the body drain directly into the _____, so
portal systems are unusual
• Approximately half of the liver’s 02 demand is met by the hepatic _____ vein, and
half is met by the hepatic _____
• Blood flows through the liver tissue and empties into the central _____ of each lobule.
The central veins course into hepatic veins that collect the blood leaving the liver, drains into the _____ which will bring it to the heart
hepatic arteries venous 75 arterial gastrointestinal heart heart heart portal arteries vein IVC
Vascular Supply
I. Vessels
1) Hepatic Artery
2) Portal Venous System
- -_____
- -_____
- -_____
3) Hepatic Veins
II. Has Dual blood supply
> _____ and _____
III. Has Portal Triad
—Branch of hepatic _____,
portal _____ and _____ ducts
—Contained within connective sheath; presenting as echogenic walls of PV when compared to HV
IV. Sono & Distinguishing Appearance
► Distinguishing Portal and Hepatic Veins
Intrahepatic Vessels and Ducts
MPV RPV LPV PV HA arteries veins bile
Hepatic Artery
• Function - carries _____ blood to liver
—Part of the Portal Triad of _____, CD, _____, therefore travels in the sheath which creates echogenic walls
• Anatomy - AO –> CHA —> PHA —> right and left hepatic arteries
SONO
–very small, especially away
from porta hepatis
–Technique - anterior approach
–Doppler - antegrade flow in
diastole, low RI
oxygenated
PV
HA
Portal Venous System - Anatomy Aka Portal Triad
Normal placement is w/in the _____ ligament (portion of the lesser omentum extending b/t porta hepatis of liver and the superior part of the duodenum; running inside of it are the structures collectively know as the portal triad)
1) CHD/CBD - Ventral (_____) and _____
2) PHA/HA - Ventral (_____) and _____
3) PV - Dorsal (_____) between _____ and _____
** porta hepatis or transverse fissure of the liver is a short but deep fissure, about ___ cm long. extending transversely beneath LT portion RT lobe of liver, separates the _____ lobe from the _____ lobe
hepatoduodenal anterior lateral anterior medial posterior PHA CHD 5 quadrate caudate
Portal Venous System - Function
• ____-____% of hepatic blood flow
• Carries incompletely 02 blood from _____, _____, _____,
Portal Venous System - Anatomy
• MPV begins with
the junction of the _____ mesenteric veins and _____ vein, posterior to the neck of the _____
—Travels _____, _____
alongside the HA
• MPV is: _____
to IVC, cephalad to _____ head, caudal to _____ lobe
50 60 spleen pancreas GB superior splenic pancrease superiorly obliquely anterior pancreatic caudate
Portal Triad Localization in Imaging
- Identify _____ in a transverse image of the mid-abdomen
- Follow the SV to its confluence with the _____ = MPV
• _____ will course superiorly and laterally toward the liver
appearing round
• Oblique the transducer _____° (on a line from the right hip to the left shoulder) until the HA and the CHD are seen = Mickey Mouse sign
SV
SMV
MPV
45 degrees
Porta Hepatis
• Gate/_____ of liver
• MPV divides into _____ and _____
branches
• the RHA and LHA enters the
_____ parenchyma
• right and left hepatic ducts exit
the liver and form the _____
hilum right left liver CHD
Portal Triad – Differentiating PHA from CHD
- Travels in _____; bright (echogenic) area around it
- Intrinsic pulsations in _____ or _____ ONLY
- A crossing artery can sharply indent a _____ or _____; reverse NOT TRUE
- Duct _____ may vary through exam and along course; arteries are uniform in caliper
- Artery may not _____ vein or may do so for only a short distance; _____ parallels vein closely
- _____ may be tortuous and loop in and out of the scan plane
- Arteries produce _____ Doppler signals; veins produce _____ Doppler signals; ducts produce _____ DOPPLER SIGNAL
sheath artery vein duct vein size parallel duct arteries pulsatile continuous NO
Right Portal Vein
• Larger more _____
and more _____ branch
- Receives _____ vein
- Divides into
• Anterior branch - central within _____ segment right lobe .
– Posterior branch -
central within _____ segment right lobe
posterior caudal cystic anterior posterior
Left Portal Vein
—Enters left lobe and joined by paraumbilical veins and ligamentum _____
—Smaller more _____ and cranial branch
—Initially (horizontal portion) anterior to caudate lobe —> ascending branch runs within left intersegmental fissure separating left medial from left lateral segments
Left Portal Vein
Divides into
- –Medial branch - central within _____ segment left lobe
- –Lateral branch - central within _____ segment left lobe
Depending on the angle or position of probe, the LPV may look differently
teres
anterior
medial
lateral
Portal Venous System - Technique
- MPV and LPV - _____ approach; “Recumbent H” = initial LPV, ascending branch LPV, medial and lateral and additional posterior/lateral branch (oblique-cranially-angled, subxiphoid)
- RPV - right _____ approach; “Recumbent H” = sagittal or oblique
anterior
intercostal
Portal Venous System - Doppler
- _____ velocity continuous flow toward liver (hepatopedal)
- occasionally may see mild undulations due to _____
- Velocity _____ during inspiration and post-prandially
low
heartbeat
increase
Hepatic Veins, Anatomy
• Function
—Carries _____ blood from liver
to IVC
• Anatomy
•Vary in number and position, generally 3 major - _____, _____, _____
–No _____
- Technique
- Transverse scan plane high in _____
deoxygenated right middle left valves epigastrium
Hepatic Veins, Anatomy:
—RHV, MHV, LHV join and enters the _____
—3 upper hepatic veins which drain the liver of _____ blood into the IVC
Right Hepatic Vein (RHV)
—-Single lies w/in _____ intersegmental fissure
Short hepatic vein
—separates RT lobe into _____ and _____ segments
Middle Hepatic Vein LHV)
> Forms common trunk w/in _____
—-lies within _____ lobar fissure
► separates _____ lobe from _____ lobe
Left Hepatic Vein
> The cephalad boundary dividing LT lobe
into _____ and _____ segments
IVC deoxygenated right anterior posterior LHV main right left lateral medial
Main Lobar Fissure
> a plane which can be
approximated by drawing a line connecting the
_____ bed and _____
> Bright (echogenic) line
seen connecting GB bed/fossa to _____
— Divides _____ and _____ lobes of
liver
—The middle hepatic vein
courses within the _____ lobar fissure
gallbladder RPV RPV right left main
Hepatic Veins Doppler
- Blood flow toward _____
- Characteristic _____ waveform or a “W” reflective of cardiac activity
IVC
triphasic
Hepatic Vein:
- -Interlobar and _____
- -Drain towards _____ atrium
- -Caliper _____ as approach diaphragm and IVC
- -_____ reflective walls
- -Branch _____
- -Caliper varies with _____
- -With an oblique coronal supxiphoid view, form a “___”, _____ shape, or “_____ bunny” sign
Portal Veins:
- -Branches of RPV and _____ intrasegmental
- -Originate from porta _____
- -Caliper _____ near porta hepatis
- -Echogenic, _____ walls
- -Branch _____
intersegmental right increases No longitudinally respiration W star playboy LPV hepatis greater reflective horizontally
RHV = Location: _____ intersegmental fissure; Usefulness: Divides cephalic aspect of right lobe into _____ and _____ segments
MHV = Location: _____ lobar fissure; Usefulness: separates _____ and _____ lobes
LHV = Location: _____ intersegmental fissure; Usefulness: divides cephalic aspect of left lobe into _____ and _____ segments
RPV = Location: _____ intersegmental fissure; Usefulness: Divides anterior and posterior segments of _____ lobe
RPV - anterior branch = Location: Intrasegmental in _____ segment of right lobe; Usefulness: Courses centrally within _____ segment of right lobe
RPV - posterior branch = Location: Intrasegmental in _____ segment right lobe; Usefulness: Courses centrally within _____ segment of right lobe
LPV - horizontal segment = Location: _____ to caudate lobe; Usefulness: Separates caudate lobe _____ from medial segment of left lobe _____
LPV - ascending segment = Location: _____ intersegmental fissure; Usefulness: Divides medial from _____ segment of left lobe
LPV - Medial branch = Location: Intrasegmental in _____ segment left lobe; Usefulness: Courses centrally within _____ segment of left lobe
LPV - Lateral branch = Location: Intrasegmental in _____ segment left lobe; Usefulness: Courses centrally within _____ segment of left lobe
GB fossa = Location: _____ lobar fissure; Usefulness: Separates _____ and _____ lobes
Fissure for Ligamentum Teres = Location: _____ intrasegmental fissure; Usefulness: Divides caudal aspect of left lobe into _____ and _____ segments
right anterior posterior main right left left medial lateral right right anterior anterior posterior posterior anterior posteriorly anteriorly Left lateral medial medial lateral lateral main right left left medial lateral
