Liver Abnormalities Quiz

Diffuse Abnormalities of the Liver Parenchyma

• Biliary obstruction is the blockage of any bile duct.
• Obstruction can be proximal or distal.
• Causes of proximal obstruction include gallstones, carcinoma of the common bile duct, and metastatic tumor invasion.
• Causes of distal obstruction include stones in the common bile duct and stricture of the common bile duct. Chronic pancreatitis or injury during cholecystectomy can lead to strictures.
• Clinically, patients may present with jaundice, itching (pruritus), and elevated levels of direct bilirubin and alkaline phosphatase in liver function tests.
• Sonograms show a tubular branching appearance with dilated intrahepatic ducts (in peripheral areas of the liver) for carcinoma of the common bile duct.
• Imaging a discrete mass lesion may be difficult.
• The gallbladder is often normal in size.

Passive Hepatic Congestion

• Passive hepatic congestion arises secondarily from congestive heart failure.
• Signs include hepatomegaly (an enlarged liver).
• Lab data usually show normal to slightly elevated liver function tests.
• Ultrasound can show a dilated inferior vena cava (IVC) and hepatic veins (HV).

Focal Hepatic Disease

• Few hepatic lesions display specific sonographic features.
• Differential diagnosis may include primary tumors, metastases, abscesses, hematomas, and cysts.

Cystic Lesions

• A hepatic cyst is usually a solitary, nonparasitic cyst of the liver.
• It's a fluid-filled mass with an epithelial lining.
• These cysts can be congenital or acquired, and can be solitary or multiple.
• Patients are often asymptomatic and don't require treatment.
• Sonographic appearance typically shows an anechoic, thin-walled structure, with well-defined borders and posterior acoustic enhancement. In some cases, polycystic liver disease may be suspected and evaluation of the kidneys and other organs might be necessary.

Simple Hepatic Cysts

• Sonographic findings are often incidental due to asymptomatic nature.
• Growth can sometimes cause pain or a mass effect suggestive of serious conditions.
• Female affectation is more common, and the right lobe is affected twice as often than the left.
• Sonographic appearance shows a lack of internal echoes, with well-defined thin walls, and oval or rounded shape. Posterior acoustic enhancement is often evident.

Pyogenic Abscess

• About 80% of hepatic abscesses are pus-forming.
• Bacteria, often Escherichia coli, can access the liver through the biliary tree, portal vein, hepatic artery, or by contiguous infection and trauma.
• Clinical signs may include fever, pain, pleuritis, nausea, vomiting, diarrhea, elevated liver function tests, leukocytosis, and anemia.
• On ultrasound, abscesses appear as hypoechoic lesions with round or oval shapes, possibly without well-defined walls; size may range from 1 cm to very large.
• Abscesses might exhibit acoustic enhancement; debris might be evident along the posterior margin, and walls might be irregular and thick.

Amebic Abscess

• An amebic abscess forms from disintegrated tissue in a cavity, usually in the liver parenchyma, caused by the protozoan parasite Entamoeba histolytica.
• Parasites reach the liver via the portal vein.
• The condition is primarily a disease of the colon, but can spread to the liver, lungs, or brain.
• Amebiasis is contracted through ingesting contaminated water or food.
• Patients can be asymptomatic or experience gastrointestinal discomfort. Clinical symptoms can include pain, diarrhea, leukocytosis, and fever.
• Ultrasound appearance varies but is typically round or oval, with a lack of well-defined wall echoes and hypoechoic when compared to normal liver parenchyma. The abscess may exhibit low-level echoes that are easier to see with higher-sensitivity imaging.

Hepatic Tumors

• A neoplasm refers to any new growth of tissue, either benign or malignant.
• Benign growths are usually contained locally; they don't spread to other places or enter surrounding structures.
• Malignant masses lack controls, and can spread to surrounding tissue or other body parts via blood or lymph.

Benign Hepatic Neoplasm

• Cavernous hemangioma: Benign congenital tumors containing large, blood-filled spaces; common in liver.
• Liver cell adenoma: Often associated with oral contraceptives; can rupture and bleed causing severe pain.
• Hepatic cystadenoma: Benign tumors; usually appear as cysts.
• Focal nodular hyperplasia: Second most common benign liver mass after hemangioma; develops in younger women, and has no known cause or risk factor.

Hepatocellular Carcinoma (HCC)

• HCC or Hepatoma is a common malignant liver tumor, frequently found in Southeast Asia, parts of Africa, Japan, Greece, and Italy; it's the fifth most prevalent cancer worldwide.
• Its development is often linked to cirrhosis, ingestion of hepatocarcinogens, and chronic hepatitis B viral infection.
• In the United States, approximately 80% of HCC cases feature pre-existing cirrhosis.
• The incidence of HCC in cirrhotic patients in the US is about 5%.
• Hepatocellular Carcinoma tends to invade hepatic veins leading to Budd-Chiari syndrome..
• Liver function tests may reveal little abnormalities, except in cirrhosis.
• Clinical symptoms can include nausea, vomiting, fatigue, weight loss, and hepatomegaly.
• There are several morphological patterns, including; solitary massive tumor, multiple nodules, and diffuse infiltrated types. Different appearances on ultrasound include (1) hypoechoic (2) complex (3) echogenic.

Liver Hemangiosarcoma/Angiosarcoma

• Rare; highly aggressive malignant tumor arising from liver blood vessels.
• Associated with thoratrast, chemical carcinogens.
• Symptoms often take decades to appear
• Mostly found in patients over 60 years; frequently shows rapid metastasis
• Common metastatic sites include the lung, spleen, lymph nodes, bone marrow, thyroid gland, and peritoneal cavity
• Sonographic appearance depends on presentation time and is not specific, but generally appears as large solid or mixed lesions.

Metastatic Disease

• Metastatic liver disease is more common than hepatocellular cancer.
• Metastasis usually begins in lymph nodes, and the liver is the most common site for this.
• Primary cancers that affect the liver include those in the gallbladder, colon, stomach, pancreas, kidneys, ovaries, breast and lung.
• A common range for the incidence of metastatic liver tumors is 18-20 times more frequent than HCC
• Approximately 40% of cancer patients show liver metastasis

Hepatoblastoma

• Hepatoblastoma is the most common primary malignant tumor in children under the age of 5.
• It's frequently connected to Beckwith-Wiedemann syndrome that shows patterns of overgrowth in body areas; it may also appear in children affected by HIV.
• High serum alpha-fetoprotein levels are observed.
• Clinical symptoms usually include hepatomegaly, palpable abdominal mass, jaundice, abdominal pain, weight loss, and anorexia.
• Sonographic imaging often shows a solid mass with an abnormal hyperechoic or heterogeneous echotexture.

Hepatic Trauma

• The liver is the third most common organ damaged during abdominal injuries after the spleen and kidneys.
• The right lobe is the most frequently injured.
• Sonographic imaging helps detect intraperitoneal or subcapsular/intrahepatic abnormalities that indicate injuries, to locate broken solid lines or fluid collections. A crescent-shaped echogenic collection along the right lateral aspect of the liver, suggests a subcapsular hematoma resulting from blunt trauma.

Liver Transplantation

• A diseased liver that is too large due to polycystic liver disease, may be replaced surgically.