Mod 4- Liver Pathology (SON107)

micronodules

0.1 - 1cm

geographic appearance locations of focal fatty sparing

1) adjacent to the porta hepatis (segment IV) 2) gallbladder fossa 3) adjacent to the falciform ligament 4) subcapsular parenchyma

Normal liver width measurement in sagittal midclavicular plane

15 cm or less.

cirrhosis

A diffuse process characterized by fibrosis and the conversion of normal liver architecture into structurally abnormal nodules.

liver cysts

A fluid-filled space with an epithelial lining Cause is unclear; may be ductal in origin May be solitary or multiple Ultrasound is superior to CT in characterizing a cystic mass

focal fatty infiltration

A localized absence of fatty change which otherwise affects the whole liver (diffuse). Areas without fatty change are referred to as "spared".

liver abscess

A pus-filled cavity within the liver, usually caused by a biliary tract source in patients with cholecystitis, choledocholithiasis, or cholangitis. (Less common sources include other intra-abdominal processes, such as appendicitis or diverticulitis, and hematogenous spread from sources such as an infected heart valve or the oral cavity) Almost uniformaly fatal if left untreated. (timely treatment reduces mortality to 5% from 30%)

reidel's lobe

A tongue-like extension of right lobe  -extends below inferior pole of right kidney during normal respiration as far caudally as the iliac crest.

benign hepatic cysts

Anechoic Thin, well demarcated walls Posterior enhancement

focular nodular hyperplasia

Believed to be formed from an area of congenital vascular malformation. More common in women than men. More common than adenomas of the liver. Usually incidentally detected on an asymptomatic patient

adult polycystic disease

Congenital Usually involved with kidney polycystic disease

ultrasound presentation of cirrhosis

Enlarged in early stages Small in advanced states with enlargement of caudate and left lobe in comparison to right (volume redistribution) Coarse echotexture and increased echogenicity Irregularity of liver surface (nodularity) Portal hypertension (Splenomegaly, ascites and formation of portosystemic collaterals)

common symptoms of liver abscess

Fever, Malaise (general feeling of discomfort), Anorexia, RUQ pain, Jaundice (25% of patients)

hemorrhagic or infected liver cysts

May cause pain and fever Internal echoes Septations May appear solid May contain air/gas if infected Thickened walls (Differential diagnosis: cystadenomas or cystic metastases)

focal liver fatty infiltration

May mimic neoplasm Regions of increased echogenicity Islands of normal liver parenchyma may appear as hypoechoic masses within a dense fatty infiltrated liver (focal fatty sparing)

diffuse liver fatty infiltration

Mild to severe Increased echogenicity Poor penetration Loss of vascular markings

CAVERNOUS HEMANGIOMAS

Most common benign tumours of the liver. More common in women (5:1 over men). Consist of multiple vascular channels lined with a single layer of endothelium. Surrounded by fibrous septae. Small, asymptomatic, discovered accidentally. Usually stable in size and appearance.

signs and symptoms of cirrhosis

Progressively worsens, therefore, depends on stage of disease Palpable liver Jaundice Abdominal bloating due to ascites Asymptomatic

moderate diffuse steatosis

Slightly impaired visualization of the intrahepatic vessels and diaphragm

hepatomegaly

Swelling of the liver beyond its normal size. Normally not palpable beyond the ribs except with deep inspiration.

ultrasound findings for focal nodular hyperplasia

Typically solitary well-circumscribed lesions with a central scar with prominent centrifugal arterial flow . Usually less than 5cm in diameter. Often produce contour abnormality to the surface of the liver or may displace the normal blood vessels within the parenchyma. Some lesions are well marginated and easily seen whereas other are isoechoic with surrounding liver. (Unlike adenomas, they are only rarely complicated by spontaneous rupture and hemorrhage)

ultrasound findings of hemangioma

Usually small (<3cm) Well defined Homogenous and hyperechoic May see posterior enhancement May have centrally inhomogenous, hypoechoic area Thin or thick rim Larger lesions tend to be more heterogenous Blood flow usually extremely slow and undetectable by ultrasound

ultrasound findings of adenoma

Usually solitary Well encapsulated 8 - 15cm May be hypo, hyper, isoechoic, or of mixed echogenicity May contain echogenic fat or calcifications May be indistinguishable from focal nodular hyperplasia (FNH) May be vascular but less so than FNH

liver abscess ultrasound appearance

Varied Most frequently cystic with fluid ranging from echo free to highly echogenic May be complex Occasionally contain gas (echogenic foci with posterior reverberation artifact-may be mobile) Internal septations; debris Walls may be well-defined or irregular and thick

ultrasound findings of granulomas

Well circumscribed, focal lesions Hepatomegaly. (due to chronic disease. Hyperechoic foci throughout liver parenchyma)

hematoma

When a blood vessel is damaged blood leaks into the surrounding tissue; this blood tends to coagulate or clot. The predominant site of hepatic injury in blunt trauma is the right lobe (Particularly the posterior segment) Fresh hemorrhage (<24 hrs) appears echogenic. Laceration becomes more hypoechoic within the first week and organized.

adenoma

a benign tumor of glandular origin. may progress to become malignant, at which point they are called adenocarcinomas. May be asymptomatic or painful due to hemorrhage. May be palpable. May rupture.

granuloma

a localized collection of chronically inflamed cells. typically asymptomatic; even extensive infiltration usually causes only minor hepatomegaly and little or no jaundice

What are linked to oral contraceptive use, therefore, more common in women?

adenomas

What is the most common cause of micronodular?

alcohol abuse

common causes of hepatomegaly

alcohol use, congestive heart failure, hepatitis, cancer.

fatty infiltration of the liver

an acquired, reversible metabolic disorder. An accumulation of triglycerides within the hepatocytes.

What is the most common cause of macronodule cirrhosis?

chronic viral hepatitis

sonographic apperance of fatty infiltration of the liver

demonstrates increased echogenicity and attenuation. The echogenic walls of the portal veins and hepatic veins are lost, due to the liver attenuation having increased. (May mimic hepatocellular carcinoma or hepatic metastasis)

causes of granuloma

drugs, infections, metabolic or systemic disorders (hepatitis, mononucelosis)

hepatic lipoma

extremely rare. Asymptomatic. Well defined, echogenic solid focal mass. (Differentials: hemangioma, metastic lesion, focal fat)

What is the second most common liver mass?

focal nodular hyperplasia

What would cause you to discover a granuloma/ calcifications?

imaging tests. Asymptomatic elevations in liver enzymes, particularly alkaline phosphatase.

What happens within 2-3 week of discovering a hematoma?

lesion becomes increasingly indistinct as the body begins to reabsorb the fluid

severe diffuse steatosis

marked increase in echogenicity. Poor penetration of posterior liver. Poor or no visualization of hepatic vessels and diaphragm

left lobe normal variant

may be elongated all the way to the spleen.

mild diffuse steatosis

minimal diffuse increase in hepatic echogenicity.

causes of liver fatty infiltration

obesity (common cause), alcohol abuse, severe hepatitis, corticosteroids, etc.

peribiliary liver cysts

seen in patients with severe liver disease Small (0.2 - 2.5cm), usually seen in clusters Located usually in region of porta hepatis May be small, obstructed periductal glands

Why might liver imaging be requested for?

suspicion of: Liver enlargement, Metabolic disorders, Liver masses/benign and malignant, Vascular abnormalities

macronodules

up to 5cm