Slide show Flashcards
The surface of the liver is covered by a fibrous peritoneum known as
Glisson’s capsule
The liver is suspended by the diaphragm and adhered to the anterior wall by the
Falciform Ligament
The normal echo brightness of the liver should be greater than the _______ and slightly less than the
reanals pancreas
Lobes of liver divided into L and R. Left lobe separates
anterior posterior segments
Lobes of liver divided into L and R. Right lobe separates
medial lateral segments
R hepatic V divides right lobe into..
Right hepatic vein divides the right lobe into anterior and posterior segments
L hepatic V
Left hepatic vein divides the left lobe into a medial and lateral part.
Main hepatic v
Middle hepatic vein divides the liver into right and left lobes. This plane runs from the inferior vena cava to the gallbladder fossa.
MLF
The right lobe of the liver can also divide from the left lobe by the main lobar fissure
right intersegmental fissure
The right intersegmental fissure divides the right lobe of the liver into anterior and posterior segments
left intersegmental fissure
The left intersegmental fissure divides the left lobe of the liver into medial and lateral segments
Ligamentum venosum
The ligamentum venosum (remnant of the ductus venosus) separates the medial segment of the left lobe from the caudate lobe
Hepatic veins
Largest vessels that drain the liver and empty into the inferior vena cava at the level of the diaphragm
What supplies blood to the liver
The portal veins and hepatic arteries supply blood to the liver
What makes up the portal triad
bile ducts, hepatic arteries, and portal veins
The majority of the blood arriving to the liver is from the…
portal system the other portion arrives from the hepatic artery
The portal system consists of 5 veins:
Splenic vein- drains blood from the spleen, stomach and pancreas
2. SMV- drains a portion of the small bowel and colon
3. IMV- drains the distal colon and rectum
4 & 5. Right and Left gastric veins- drain the esophagus and portion of the stomach
The blood drains from… into the…. into the…
Hepati veins, ivc and into heart
Measurements are made to the liver are taken..
superior inferior dimension
Hepatomegaly
greater than 15cm
Reidel’s lobe
This is a normal variant that appears as hepatomegaly
It is seen as a tongue like extension on the inferior portion of the right lobe of the liver
The liver manufactures plasma proteins found in the body and converts excess amino acids
to fatty acids and urea
Liver tests are used
AST (SGOT) Aspartate aminotransferase ALT (SGPT) Alanine aminotransferase LDH Lactic acid dehydrogenase Bilirubin Prothrombin time Albumin and globulins Alk pos
AST-
elevated in liver disease patients
demonstrates that there is injury or death to liver cells, thus this enzyme is released into the blood stream
ALT-
evaluates liver function and elevates mildly with acute cirrhosis & pancreatitis
Is highly elevated with hepatocelluar disease
Alk pos- (alkaline phosphatase)
is elevated when there is hepatic obstruction or liver disease
Bilirubin
Bilirubin is the product from the breakdown of hemoglobin in old red blood cells
The liver converts the hemoglobin into bile
3 ways that lead to high bilirubiun
EXCESSIVE RED BLOOD CELL DESTRUCTION
MALFUNCTION OF LIVER CELLS
BLOCKAGE OF BILE DUCTS
Prothrombin time
Prothrombin is an enzyme in the blood that allows the blood to clot
Diffuse hepatocellular disease
abnormal LFTs, alk phos and bilirubin increase effects hepatocytes
Fatty infiltration
a benign process that can be reversed with a patients lifestyle change
Common causes are alcoholic abuse, diabetes, and obesity
CLUE- dense
The most common areas for FFS is the
gallbladder, caudate lobe, and portal vein areas
Hepatitis
THE LIVER IS INFLAMED
Hep A
spreads by fecal contamination
Oral anal contact
Contaminated food
Hep B
hepatitis can be contracted from infected blood
seminal fluid, vaginal secretions, or contaminated drug needles, including tattoo or body-piercing equipment
it can also be spread from a mother to her newborn
The greatest risk to health workers
Hep C
The infection is often asymptomatic, but once established, chronic infection can progress to scarring of the liver
advanced scarring (cirrhosis) could continue into liver cancer.
spread by blood-to-blood contact
Sexual activity and needle use are very common routes of transmission
Acute hepatitis
may have mild to massive necrosis and possibly liver failure
Patients initially present with flu like symptoms and abnormal LFT’s
Sono findings in acute hepatis
May appear normal
Portal vein borders are more prominent than usual
Liver parenchyma is slightly more echogenic.
Gallbladder wall might be thickened
Chronic hepatitis
Is an inflammatory process of the liver that is longstanding
Chronic hepatitis can eventually lead to cirrhosis and liver failure
Bx can determine the extent of the disease
On ultrasound the liver texture appears coarse
Fibrosis
is a disease process that gives the liver a coarse texture
Cirrhosis
This is a disease process in which the liver parenchyma degenerates and the lobes are infiltrated with fat
The most common cause of cirrhosis is alcohol abuse
CIrrhosis clinical symptoms
Clinical symptoms include: Nausea Flatulence Anorexia Weight loss Varicosities
Sonographic findings of cirrhosis
When the cirrhosis is not very advanced the liver may appear hyperechoic and coarse
When the disease progresses a nodular contour is evident
Early stages of cirrhosis shows hepatomegaly, ascites and decreased vasculature
End stage cirrhosis; the liver becomes small and nodular that is generally surrounded by ascites
The Doppler flow patterns may also be disrupted
May appear normal in the early stages
May begin to have a coarse texture accompanied by fatty change and hepatomegaly
Late stages- small liver with nodular surface
Appearance of Cirrhosis, Signs of portal hypertension:
Possible thrombosis Varices and collaterals Other signs Ascites Splenomegaly Lymphadenopathy
Biliary Obstruction Proximal
Biliary obstruction proximal is caused by a mass that evades the porta hepatis
Clinically the patient will be jaundiced and the LFT’s will be elevated
Ultrasound is important to document mass location and size
Biliary obstruction distal
A biliary obstruction distal to the cystic duct is usually caused by stones in the CBD
Stones in the duct usually cause significant amount of RUQ pain, jaundice and elevated labs
On ultrasound you will see a dilated duct with hyperechoic shadowing stones
Hepatic cystic lesions
Liver cysts are common and usually benign
Most patients are asymptomatic
Patients that have large cysts are at a risk for compressing the hepatic vascular structures and ductal system
Simple cysts
The cyst is seen on ultrasound as a thin, smooth walled structure with posterior enhancement
Increased thru transmission
Hepatic cysts
A hepatic cyst can lead to a more serious condition such as infection, abscess, and necrosis
The cyst can also hemorrhage
Seen more commonly in women
Polycystic liver disease
The liver is infiltrated with small 2-3 cm cysts
Affects 1 in 500 people
Many of these patients are asymptomatic unless the cysts change( abscess formation) or start to compress the biliary system
A majority of these patients also have polycystic renal disease
Inflammatory disease of the liver - Pyogenic abscess
A pyogenic abscess is one that contains “pus”
They usually arise because of trauma, surgery, biliary disease, wound (knife)
Patient presents with fever, increased WBC’s, and RUQ pain
Hepatic Candidiasis
It is caused by a fungus (Candida) that occurs in persons that are immunocompromised (HIV, Chemo pts.)
Presents with a fever and localized pain.
On ultrasound the liver presents with small hypoechoic masses with a echogenic center referred as a target lesion “very characteristic”
shows diffuse, homogeneous, hypoechoic foci
Small amount of fluid in morrisons pouch
Chronic granulomatous
The is a genetic disease process that renders the patients ability to ward off types of bacteria
Occurs more frequently in children and girls
A hypoechoic mass is identified with calcifications
Amebic abscess
Contracted by ingesting a parasite found in contaminated food or water
A collection of pus is found in the liver
Not so common in the US-but ask the pt. if they have traveled out of country recently
The parasite reaches the liver via the portal vein
The sonographic findings are non specific
Liver abscess
Echinococcal cyst
This infectious disease is found in sheep herding areas of the world
It is cause by a tapeworm that resides in dogs (the dog eats the meat from the infected livestock)
The eggs are deposited in the feces
The larvae burrow through the intestinal wall and enters the portal circulation to travel to the liver
The parasite causes the liver to form cysts which impinge on the hepatic blood vessels
Echinococcal cyst Sono findings
On ultrasound several patterns may be seen
Simple cyst
Complex mass
Calcifications
Honeycomb appearance
If a daughter cyst is found it is specific for this disease
Neoplasm
is defined as new growth of tissue, can be benign or malignant that does not invade surrounding structures
Ex: Mole
Cavernous hemangioma
Sonographically the mass is seen as hyperechoic with acoustic enhancement
The older larger hemangiomas have mixed texture patterns because of necrosis
Liver cell adenoma
This tumor is usually seen in women who take oral contraceptives
Patients present with RUQP secondary to rupture and bleeding into the tumor
On ultrasound it is identified as a mass with non specific findings (multiple image appearances )
Hepatic cystadenoma
Rare neoplasm that presents itself as a palpable abdominal mass
It is seen to contain cystic structures within the mass (multilocular)
Focal nodular hyperplasia
Second most common benign liver mass after hemangioma
Tumors are asymptomatic unless bleeding occurs
FNH is a condition in which a nodule, composed of a central scar tissue and clumps of surrounding liver cells, is found within an otherwise healthy liver
Focal nodular hyperplasia - Sono findings
On ultrasound lesions are presented with well defined hyperechoic to isoechoic patterns
These masses arise in women under 40 years of age and an increased incidence in women taking oral contraceptives
Portal hypertension
Occurs when the pressure in the portal venous system is increased
This results from chronic liver disease or thrombus in the PV
The fibrosed nature of the liver impedes the flow of blood into the liver
PV hypertension - Sono findings
A normal PV should not exceed 16 mm in AP diameter
PV hypertension the vein appears dilated and tortuous
Ascites is usually noted
Splenomegaly results from back pressure in the portal and splenic veins
Varices develop to re-route blood away from the portal system
These vessels are very prone to bleeding
The umbilical vein may become recanalized secondary to portal hypertension
Metastases
The liver is one of the most common sites in which malignant tumors metastasize
Acoustic appearances of liver metastases are extremely variable
When compared to surrounding liver parenchyma metastases may be hyperechoic, hypoechoic, isoechoic, or complex
Metastases - Sono findings and primary sites
Most metastases tend to be solid with ill defined margins
If the findings of metastases is unexpected it is useful to search other organs to find the primary carcinoma
Internal echoes within the major veins suggests tumor invasion
Primary sites- colon, breast, lungs
Hepatocellular carcinoma
It is related to cirrhosis- 80% of patients with long standing cirrhosis develop hepatocellular carcinoma
Clinically patients present with palpable mass in the liver, and signs of cirrhosis
More frequent in men
HCC causes no abnormal LFTs
Clinically these tumors are multiple or solitary
Cause a rise in alpha-fetoprotein (AFP)
Color and spectral Doppler can demonstrate vigorous flow, helping to distinguish HCC from metastases or hemangioma, which demonstrate little or no flow
AFP
In adults, high blood levels of AFP are seen in only four situations:
HCC
Germ cell tumors (cancer of the testes and ovaries)
Metastatic cancer in the liver (originating in other organs)
Pregnancy
Congestive cardiac disease
Patients with cardiac failure frequently demonstrate dilated hepatic veins in the liver
Patients with cardiac failure frequently demonstrate dilated hepatic veins in the liver
partial or complete occlusion of the hepatic veins
Causes for occlusion:
Coagulation disorders
Tumor invasion
Congenital web obstructing in IVC (surgically removable)
In acute stages the liver may be hyperechoic and enlarged
As the disease progresses, compensatory hypertrophy of any “spared” segments occurs-usually the caudate lobe because it is inferior to the main hepatic veins
Budd-Chiari Syndrome - Treatment
partial or complete occlusion of the hepatic veins Treatment: Anticoagulants Shunts Transplant
Hepatic trauma
The need for surgery is determined by the laceration size and the patients clinical status
Hematomas are usually seen with large lacerations
CT is more sensitive to examine the extent of the liver damage
