AB-Liver Flashcards
Budd Chiari disease
uncommon, often dramatic illness caused by thrombosis of the hepatic veins or inferior vena cava.
20% are reported to be portal vein thrombosis
Budd Chiari often occurs in patients with..
Hypercoaguable states
Oral contraceptives
Collagen vascular diseases
Hepatic tumors
Clinical findings for Budd Chiari
Ascites Elevated liver function test Hepatomegaly Splenomegaly Upper abdominal pain
Sonographic findings for Budd Chiari
Reduced visualization of the hepatic veins
Thrombus within the hepatic veins
Enlarged caudate lobe
Lack of flow within the hepatic veins with color Doppler
Narrowing of the inferior vena cava
Fatty infiltration of the liver
An acquired and reversible disease
Benign
Increased lipid accumulation in the hepatocytes leading to impaired or excessive metabolism of fat
Clinical findings for fatty liver
Asymptomatic Alcohol abuse Chemotherapy Diabetes mellitus Elevated liver function test Obesity Pregnancy
Sonographic findings for fatty liver
Diffusely echogenic liver
Liver may appear patchy, inhomogenous due to focal sparing
Liver is enlarged(hepatomegaly)
Increased attenuation of the sound beam
Walls of the hepatic vasculature and diaphragm will not be easily imaged(secondary to increased attenuation)
Compare the echogenicity of the right kidney to the liver.
Glycogen storage disease
Is an inherited disease characterized by the abnormal storage and accumulation of glycogen in the tissues, especially the liver and kidneys.
Type I glycogen storage disease
von Gierke’s disease
Most common type
Abnormally large amounts of glycogen are deposited in the liver and kidneys
Glycogen storage disease is associated with..
Hepatic adenomas
Focal nodular hyperplasia
Hepatomegaly
Sonographic findings for glycogen storage disease
Hepatomegaly
Increased echogenicity
Slightly increased attenuation (similar to diffuse fatty infiltration)
Hepatocellular carcinoma (HCC)
Most common primary malignant neoplasm
Related to cirrhosis, hepatocarcinogens in food, and hepatitis B and C
Symtoms-unexplained mild fever and weight loss, hepatomegaly
Appearance for hepatocellular carcinoma
Varies from solitary mass to diffuse infiltration or multiple tumors
Invades portal venous system and hepatic vein
Heterogenous masses scatered throughout the liver
Mass with a hypoechoic halo
Clinical findings for hepatocellular carcinoma
Elevated alpha-fetoprotein Abnormal liver function tests Cirrhosis Chronic hepatitis Unexplained weight loss Hepatomegaly Fever Palpable mass Ascites
Ligaments and fissures in the liver
Glisson’s capsule-thin connective tissue covering the liver
Main lobar fissure-boundary between right and left lobes of the liver; hyper echoic line extending from the PV to the neck of the GB
Falciform ligament- extends from umbilicus to the diaphragm in a parasagittal plane and contains the ligament teres
Ligament teres-bright echogenic triangle on transverse scan; separates the medial and lateral segments of the left lobe
Ligamentum venosum- separates the left lobe from the caudate lobe
Severe hepatocellular disease lab value tests
Elevation of AST and ALT
Levels frequently exceed 1000 units
Hemangioma
benign, congenital tumor consisting of large, blood-filled cystic spaces
Most common benign tumor of the liver
More frequent in women
Asymptomatic-may bleed, RUQ pain
Sonographic findings for hemangioma
Most are hyper echoic with enhancement
Round or oval, well defined
Larger masses may show necrosis, degeneration, calcification
Extrahepatic masses
Internal invagination or discontinuity of the liver capsule
Formation of the triangular fat wedge
Anteromedial shift of the IVC
Anterior displacement of the right kidney
Intrahepatic masses
Displacement of the hepatic vascular radicles
External bulging of the liver capsula
Posterior shift of the IVC
Focal Nodular Hyperplasia (FNH)
Second most common benign tumor seen in women <40 years old
Asymptomatic
Appears as a subtle liver mass usually <5cm
Has a well developed central and peripheral blood vessels coursing through seen with Color Doppler
Hepatoblastoma
Most common malignant tumor of childhood High incidence with children who have Beckwith-Wiedemann syndrome
Elevated Alkaline Phosphatase
Associated with biliary obstruction or the presence of mass lesions in the liver
Acute cholecystitis
*Produced by the liver, bone, intestines, and placenta
Good indicator of intrahepatic or extrahepatic obstruction, hepatic carcinoma, abscess, or cirrhosis
Liver
Largest organ in the body next to skin
Weighs approx. 1500g in the adult
Intraperitoneal organ
Location of the liver
Occupies almost all of the right
hypochondrium, the greater part of the epigastrium, and the left hypochondrium as far as the mammillary line.
Inferior to the diaphragm
The posterior border is in contact with the
right kidney and inferior vena cava
The aorta lies posterior to the left lobe of the
liver
Subphrenic Space
Between the liver and the diaphragm; a common site for abscess formation
Morison’s pouch
In the right sub hepatic space
Common space for peritoneal fluid or blood to collect
Lesser sac
Enclosed portion of the peritoneal space posterior to the liver and stomach is another site for abscess formation
Bare Area
Area superior to the liver that is not covered by peritoneum so that the IVC may enter the chest
Lobes of the liver
Right Lobe-largest lobe. Contains 3 fossae-porta hepatis, gallbladder, IVC
Left Lobe-size varies; found under xiphoid process
Caudate Lobe-small lobe; situated inferior to the ligamentum venous and superior to the IVC
Riedel’s Lobe
A congenital variant, can sometimes be seen as an anterior projection of the liver sometimes extending down to the iliac crest
Portal venous system
Supplies 80% of the blood flow to the liver from the digestive system
Low velocity, phasic flow
Main Portal Vein-enters portahepatis; 11-12mm
Right Portal Vein-largest, further divides into anterior and posterior branches
Left Portal Vein-Medial and Lateral branch
Portal vein vs Hepatic vein
Hepatic vein:
Flows into the IVC
Have hepatofugal flow (below the baseline)
Lacks bright walls
Portal vein:
Have bright walls due to the increased connective tissue – Glissons capsule
Have hepatopedal flow (above the baseline)
Hepatic Veins
Drain the blood from the liver back into the
IVC
Divided into 3 components Right (RHV),
Middle (MHV) and Left (LHV)
Doppler signal is low velocity but more
pulsitile than the portal vein due to the closer proximity to the heart
Hepatic Arteries
Supplies blood to the liver, 20%
Branch of the celiac trunk from aorta
Courses toward the right, changing names to the proper hepatic artery as it curves anterior and cephalic towards the portal hepatic
At porta hepatis, the proper hepatic artery divides into right, left, and middle
Portal triad
Common bile duct, hepatic artery, portal vein
“Mickey mouse” sign-transverse scan
RHA courses between bile duct and portal vein
Function of the liver
Metabolism:
Carbohydrate-converts glucose to glycogen and stores it
Proteins-converts excess amino acids to fatty acids and urea. Manufactures many of the plasma proteins in blood.
Digestion-secretes bile, aids digestion of fat
Storage-stores iron and certain vitamins
Detoxification-drugs and poisons that enter the body
Phagocytosis-bacteria and worn out blood cells
Kupffer cells
Macrophages These cells engulf and breakdown toxic matter such as microorganisms, dead cells and chemicals. Ingest microorganism (phagosome) by phagocytosis. Lysosmes in the cytoplasm of kupffer cell, fuse with the phagosome and release digestive enzymes. These enzymes breakdown and kill the microorganism.
Hepatic enzymes
Enzymes are protein catalysts used
throughout the body in all metabolic processes.
Due to the liver being a major center for metabolism, large quanities of enzymes are present in the hepatocytes.
The liver enzymes may leak into the
bloodstream when the liver cells are damaged or destroyed due to disease.
The presence of increased quanities of
enzymes in the blood is a sensitive indicator of a hepatocellular disorder
Liver function tests
AST ALT LDH Alk phos Bilirubin PT Albumin and globulins
Evaluate the liver for..
The size of the liver in the longitudinal plane
Attenuation of the liver parenchyma
Liver texture
Presence of hepatic vascular structures, ligaments, and fissures
Hepatopetal
Normal flow is toward the liver
Hepatofugal
Normal flow away from the liver
