Fatty Liver Disease

fatty liver disease is also referred to as

hepatic steatosis

hepatic steatosis

is a disorder characterized by fatty deposits (triglycerides) within the hepatocytes

FLD can be classified as

nonalcoholic fatty liver disease and alcoholic fatty liver disease

nonalcoholic liver disease

most common liver disorder in the Western World, and the most common cause of chronic liver disease

nonalcoholic liver disease is both

acquired and reversible

causes of nonalcoholic liver disease

starvation, obesity, chemotherapy, diabetes mellitus, hyperlipidemia, pregnancy, glycogen storage disease or von Gierke disease (glycogen storage disease type 1), total parental hyperalimentation, severe hepatitis, cystic fibrosis, intestinal bypass surgery for obesity, and the use of some drugs such as corticosteroids

fatty liver disease is also the hepatic manifestation of a disorder known as

metabolic syndrome and can lead to steatohepatitis

steatohepatitis

is inflammation of the liver that has been shown to be a precursor for chronic liver disease, leading to fibrosis, cirrhosis, and hepatocellular carcinoma

fatty changes within the liver can also be

diffuse or focal

diffuse infiltration

will cause the liver to appear diffusely echogenic, and it will be more difficult to penetrate

in the presence of diffuse fatty infiltration,

the walls of the hepatic vasculature and diaphragm will not be easily imaged, secondary to the attenuation of the sound beam

sagittal image of a diffusely fatty liver that demonstrates the inability to clearly visualize the diaphragm

sagittal image of the liver demonstrating an area of focal fatty infiltration

sagittal image of the liver demonstrating focal fatty sparring

the liver segment affected by focal fatty infiltration will appear as

an area of increased echogenicity and can thus appear much like a solid, hyperechoic mass

the liver segment affected by focal fatty sparring will appear as

a solid, hypoechoic mass or possibly even fluid

it is more likely that the signs of sparring and infiltration are seen adjacent to

the gallbladder, near the porta hepatis, and the left medial segment

clinical findings of fatty liver disease

• asymptomatic

• alcohol abuse

• chemotherapy

• diabetes mellitus

• elevated liver function test (specifically AST and ALT)

• hyperlipidemia

• obesity

• pregnancy

sonographic findings of diffuse fatty liver disease

1. diffusely echogenic liver

2. increased attenuation of the sound beam

3. wall of the hepatic vasculature and diaphragm will not be easily imaged

sonographic findings of focal fatty infiltration

hyperechoic area adjacent to the gallbladder, near the porta hepatis, or part of a lobe may appear echogenic

sonographic findings of focal fatty sparring

1. hypoechoic area adjacent to the gallbladder, near the porta hepatis, or part of a lobe or an entire lobe may be spared

2. can appear much like pericholecystic fluid when identified adjacent to the gallbladder