AB1 Ch. 7-8 Flashcards
Liver and Biliary System
GB congenital anomalies
-Floating GB: low position in abdomen
-Hypoplasia: under development
-Agenisis: failure of the GB to develop
GB variants
-Bilobed: hourglass shaped
-Septated: 1 or more divisions of the GB
-Junctional fold: fold seen at the body and the neck of GB
Hepatic Oxygenation of blood -> liver
The remaining 25% of blood to liver
How much blood does the Portal System provide to the liver
75%
Image protocol for the liver to include the MPV
-phasic flow
-response to respirations
-cont., forward
-low velocity
-increase flow on resp.
Morrison’s pouch
In between liver and kidney
Epiploic of Winslow
Passageway between greater/lesser sacs just inferior to liver.
Normal Measurement of Liver
RT Lobe: 13-17 cm (length)
5-6 cm (width)
LT Lobe: variable
How to measure the Liver
Measure superior to inferior (very top left to very bottom right)
Elongated Left lobe
Extension of the left lobe laterally (can extend all the way to the spleen!)
Glisson’s Capsule
Encloses the liver with a fibrous capsule. (Highly echogenic)
Ligamentum Venosum
Was the duct venous that collapsed after birth. Separates LT lobe from Caudate lobe.
Falciform Ligament
Thin, sickle shaped fibrous structure. Not seen unless ascites is present!
Main Lobar Fissure
-Separates the RT/LT lobes.
-Main HV is located here.
-Identified location of the GB Fossa
Ligamentum Teres
aka “The Bulls-eye Lesion”
-Left umbilical vein after birth becomes ligament teres.
-Courses between medial/lateral segments of the left lobe.
Echogenicity of Liver to other structures:
-Pancreas (hypoechoic/isoechoic)
-RT Kidney (hyperechoic/isoechoic)
-Spleen (hypoechoic)
Protocol of Liver to include MPV
Image RT lobe to include MPV, color showing direction.
US appearance of CBD/GB
CBD: avascular anechoic tubular, thin bright walls
GB: Anechoic, thin bright walls and pear shaped
CBD/GB location
GB: In main lobar fissure
CBD: Anterior to Portal Vein
GB Wall measurement
(Less) <3 mm
GB Fossa
Indentation of RT lobe near GB
GB sections
neck, body, fundus
Route of Bile from Liver to GB
CCK secretion -> GB contracts -> Sphincter of Oddi relaxes -> Bile goes into cystic duct -> flows through CBD and enters duodenum
Diameter of Bile Duct
4-8mm
Hepatic Artery max is 2-6mm
normal measurment is 1-7 mm
Porta (gate) Hepatis (liver)
3 structures w/n hepatoduodenal ligament
Bile Duct is ventral/lateral
Hepatic Artery is ventral/medial
Portal Vein is dorsal
CCK
cholecystokinin, stimulates GB contractions
Spiral Valves of Heister
Fold that controls bile flow in cystic duct.
CBD is formed by
Common Hepatic and Cystic Ducts
Preprandial vs. Postprandial
pre: before meal
post: after meal
CBD Measurement
1-7mm
can be 10 after cholesectomy or age (40+)
Functions of Biliary Tract
Drains liver of bile, stress bile, and supplies blood to GB
Hartmans Pouch
Small sacculation on the GB neck.
(ABNORMAL)
Phrygian Cap
GB fundus is folded onto itself. (NORMAL/VARIATION/HAT)
Clinical Indications for Biliary Tract
-RUQ (primary)
-+ Murphy sign (pin-point tenderness)
-Nausea
-Vomiting
-Pain in RT shoulder
-Jaundice/abnormal LFT’s
-Loss of appetite
-Intolerance to fatty/dairy foods
IVC is ___ to the Caudate Lobe
Posterior
Portal Veins
DECREASE in size as they near the diaphragm. Echogenic/Bright due to collagen tissues in WALLS
Cont., Monophasic, Hepatopetal blood flow
Portal Veins
Portal veins are intra or intersegmental?
INTRASEG.
RT Intersegmental Fissure
Divides RT Lobe into anterior and posterior segments.
Hepatic Veins
INCREASE in size when draining TOWARDS diaphragm.
-Anechoic
-No echogenic walls
Triphasic, Pulsate, Hepatofugal blood flow
Hepatic Veins
Is the Hepatic Veins INTER or INTRAsegmental
Intersegmental
LT Intersegmental Fissure
Divides LT Lobe into medial and lateral segments
Reidels Lobe
Tongue-like inferior extension of RT lobe that goes caudally to the iliac crest. Seen frequently in thin women.
The diaphragm is ___ to the Liver
Superior
Caudate Lobe
Smallest Lobe
-Lies posterior/superior to the RT Lobe
LT Lobe
Varies in size
-Falciform lig. and ligamentum teres are located w/n this lobe
-supplied by left portal vein
RT Lobe
6x larger than LT lobe
-supplied by right portal vein
Location of Liver
Inferior to dome of diaphragm.
-Occupies major portion of RUQ.
What is divided by the Hepatic Veins
The Liver. The different lobes come from the HV’s
Functions of the Liver
-Bile production
-Excretion of Drugs, Bilirubin, Cholesterol, and Hormones
-Metabolizes fats, proteins, and carbs
-Enzyme activation
-Storage of vitamins and minerals
-Synthesis of plasma protein s.a. albumin and clotting factors
-Blood purification/detoxification
US appearances of Renal Cortex (KIDNEY)
Hypoechoic to Liver
US appearance of Liver
homogeneous (smooth) and somewhat echogenic
Segments of Hepatic Veins
These separate the LT/RT lobes
LT HV
Medial/Lateral division of LT lobe.
Middle HV
LT/RT division
RT HV
Anterior/Posterior division of RT lobe.
Hepatopetal vs. Hepatofugal
Towards= Petal (normal)
Away= Fugal (abnormal)
Function of the Portal Vein
Carries blood and nutrients from abdominal bowel to the liver.
(For metabolism and detoxification)
Couinads Liver Segments
8!
-Used for hepatic lesions localization (Surgeons)
-Clockwise rotation
Normal blood flow
RED on Color Doppler- blood flowing towards liver.
US appearances of portal vein
-Anechoic tubular structure
-Bright echogenic walls
-spontaneous, phasic flow, intrasegmental
Normal size for MPV
-13mm (diameter)
-5-6cm (length)
diameter should NOT increase 1.3cm
How to measure the MPV
inner wall to inner wall
Obtaining Doppler for MPV
-Tell your PT to “Just stop breathing” or “Don’t take a breath or exhale”
-Phasic Flow (above baseline)
-Continuous
What forms the MPV
Spenlic Vein and Superior Mesentric Vein
-courses superiorly 5-6cm then divides into RT/LT branches.
3 Main Tributaries of Portal System
-Splenic Vein (SPV)
-Superior Mesentric Vein (SMV)
-Inferior Mesentric Vein (IMV)
Appearance of Bile Ducts
Avascular, anechoic tubular structures
Bare Area
A portion of the posterior surface of the liver without a peritoneal covering.
Situs Inversus
The transverse scan on a newborn, demonstrating the liver in the LUQ
Hepotomegaly
Enlarged Liver
Sonographic Sign to Differentiate CBD and Hepatic Artery
Pulsation should only be exhibited from an artery or vein
Portal Triad
-Main Portal Vein
-Proper Hepatic Artery
-Common Hepatic Duct
Probe/Frequency for scanning the Liver
1-9MHz for the Adult Liver
Curved Array
Harmonics
Helps reduce artifacts.
Gastroesophageal Junction (GEJ)
Located between aorta and edge of Liver.
Liver Parenchyma
Made up of 50-100k individual lobules. Parenchyma means “tissue”
The Portal Hepatic/Hilium of the Liver
A fissure where the major vessels and ducts enter/leave the organ. The major structures traversing Porta Hepatis are the
-Portal Vein
-Hepatic Artery
-Hepatic Duct
+ Murphy Sign
When you apply pressure onto the patient, there will be focal (pin-point) tenderness.
Frequency for GB
2-5MHz
Curved Array
Improper PT Prep can lead to…
incorrect measurements of the GB Wall.
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