Ultrasound signs of liver pathology

Liver / hepatomegaly enlargement: with homogeneous echostructure

If the liver is enlarged, but has a normal homogeneous ehostruktura, then this can be due to the following reasons:

1. Heart failure. Hepatic veins will be enlarged. There is no change in the diameter of the inferior vena cava depending on the phase of the respiratory cycle. Look for an effusion in the pleural cavity above the diaphragm.
2. Acute hepatitis. There are no specific echographic signs of acute hepatitis, but the liver can be enlarged and painful. Ultrasound can be useful for the exclusion of other liver diseases, as well as in the presence of jaundice in the patient - for differential diagnosis of obstructive and non-obstructive forms. As a rule, the ultrasound can not give more information on suspected hepatitis.
3. Tropical hepatomegaly. The only significant finding is the enlargement of the liver, usually in combination with an increase in the spleen.
4. Schistosomiasis. The liver can be echographically normal or enlarged, with a thickening of the portal vein and its major branches, whose walls and tissue near them become more echogenic, especially around the portal vein. The splenic vein can also be enlarged, and if there is portal hypertension, splenomegaly will occur. Collaterals develop in the gates of the spleen and along the medial edge of the liver. They look like crimped, anechogenic, vascular structures that need to be distinguished from a liquid-filled intestine. (Observation during some time interval will reveal peristalsis of the intestine.) Periportal fibrosis develops with Schistosoma mansoni and S. Japonicum.

Liver enlargement: with heterogeneous ehostruktura

1. Without focal formations. If there is an increase in the echogenicity of the liver parenchyma with depletion of the vascular pattern of the peripheral branches of the portal vein, cirrhosis, chronic hepatitis, fatty hepatosis can occur . To establish an accurate diagnosis, a liver biopsy may be required. In some cases, deep sections of the liver are practically not visualized, so the hepatic veins can not be identified. With a normal echographic picture of the liver, cirrhosis is not excluded.
2. With multiple focal formations. Multiple focal formations of different size, shape, and echostructure. Creating heterogeneity of the whole liver are observed when:
   • Macronodular cirrhosis. The liver is enlarged with echogenic formations of various sizes, but with a normal stroma. The vascular pattern is changed. There is a high risk of malignancy, but this can only be detected with a biopsy.
   • Multiple abscesses. Abscesses usually have fuzzy contours, reinforcement of the posterior wall and internal echostructure.
   • Multiple metastases. They can have an increased echogenicity, can be hypoechoic with clear contours or fuzzy contours, can be simultaneously metastases of different echostructure. Metastases are usually more numerous and more diverse than abscesses; multinodular hepatocarcinoma can also give metastases.
   • Lymphoma. It can be suspected in the presence of multiple hypoechoic foci in the liver, usually with fuzzy contours, without distal acoustical amplification. With ultrasound, it is impossible to distinguish between lymphoma and metastases.
   • Hematomas. They have usually fuzzy contours and distal acoustical amplification, however at the organization of blood clots the hematomas can become hyperechoic. It is important to clarify the presence of a history of trauma or anticoagulant therapy.

It is not so easy to differentiate liver abscesses, metastases, lymphomas and hematomas only from ultrasound data.

Small liver / shriveled liver

With micronodular cirrhosis of the liver, there is a diffuse increase in echogenicity and deformation as a result of cicatricial and hepatic vein scarring. This is often combined with portal hypertension, splenomegaly, ascites, enlargement and varicose transformation of the splenic vein. The portal vein can have a normal or reduced diameter of the intrahepatic part, but can be increased in the extrahepatic section. If there are internal echostructures in the lumen, there may be a thrombosis that extends to the splenic and mesenteric veins. In some patients with this type of cirrhosis in the early stages of the disease, the liver looks normal.

Cystic formations in normal or enlarged liver

1. A solitary cyst of the liver with clear contours. Anechogenous formation with distinct contours, rounded, with acoustic enhancement, usually less than 3 cm in diameter, usually asymptomatic. More often is a congenital solitary simple liver cyst. It is impossible, however, to exclude the presence of a small parasitic cyst, which can not be echographically differentiated.
2. A solitary cyst with a "dug", uneven contour.
3. Multiple cystic formations. Multiple round forms of formation of various diameters, almost anehogennye, with a clear contour and dorsal acoustical amplification can take place with congenital polycystosis. It is necessary to look for cysts in the kidneys, pancreas and spleen; congenital polycystic is very difficult to differentiate with parasitic cysts).
4. Complicated cyst. Hemorrhages and festering cysts can lead to the appearance of an internal echostructure and simulate an abscess and a necrotically altered tumor.
5. Echinococcal cyst. Parasitic disease can give a wide range of echographic changes.

Before carrying out fine needle aspiration of a solitary cyst, examine the entire abdominal cavity and perform a chest X-ray. Parasitic cysts are usually multiple and can be dangerous when aspirated.

[1], [2]

Differential diagnosis of lesions in the liver

It is difficult to differentiate hepatocellular carcinoma from multiple metastases to the liver or abscesses. Primary cancer usually develops as a single large formation, but multiple formations of different sizes can also be detected, and echostructure usually occurs with a hypoechoic rim. The center of education can be necrotized and look almost cystic, with fluid-containing cavities and a thick, uneven wall. Sometimes it is very difficult to differentiate such tumors from abscesses.

[3], [4]

Single solid formation in the liver

A variety of different diseases can cause the appearance of single solid formations in the liver. Differential diagnosis is sometimes very complicated and requires in some cases a biopsy. Single, with clear outlines of hyperechogenic formation located under the capsule of the liver, can be hemangioma: 75% of hemangiomas have dorsal enhancement without acoustic shade, but at large sizes they can lose their hyperechogenicity, and in this case they are difficult to differentiate from primary malignant tumors of the liver. Sometimes there are multiple hemangiomas, but they usually do not give any clinical symptoms.

It can be extremely difficult to differentiate hemangioma from solitary metastasis, abscess, parasitic cyst. The absence of clinical symptoms largely indicates the presence of hemangioma. To confirm the diagnosis, you may need to perform a CT scan, angiography, magnetic resonance imaging or radioisotope scanning with labeled erythrocytes. Absence of other cysts allows to exclude parasitic disease. In the presence of internal hemorrhage, the ultrasound pattern can simulate an abscess.

Single formation with a homogeneous ehostruktura and gipoehogennym rim around the periphery is most likely a hepatoma, but the hepatoma can also have central necrosis or can be presented as a diffuse heterogeneity, or can be multiple, and infiltrate the portal and hepatic vein.

Abscess of the liver

It is difficult to differentiate bacterial abscess, amoeba abscess and infected cyst. Each of them can be represented by multiple or single formations and usually looks like a hypoechoic structure with reinforcement of the posterior wall, uneven contour and internal sediment. Gas can be detected in the cavity. Bacterial infection can be layered on a cold amoeba abscess or occur in the cavity of a cured amoeba abscess. Necrotized tumor or hematoma can also simulate an abscess.

[5], [6], [7]

Amoebic abscess

In the early stages of development, amoebic abscesses can be echogenic with fuzzy contours or even isoechogenic, not visualized. Later they look like formations with uneven walls and acoustic amplification. Inside a sediment is often determined. As the infection progresses, the abscess acquires more distinct contours: the sediment becomes more echogenic. Similar changes take place with successful treatment, but the abscess cavity can persist for several years and simulate the cyst. The scar after the cure of the amoeba abscess exists for any length of time and can be calcined.

Amoebic abscesses in the liver

• Usually single, but can be multiple and have different sizes.
• More common in the right lobe of the liver.
• Most often occur under the diaphragm, but may also occur elsewhere ..
• Clearly respond to the introduction of metronidazole or other adequate therapy.
• They can be isoechoic and not be visualized on the first examination. If the abscess is suspected clinically, repeat ultrasound at 24 and 48 h.
• Can not clearly differentiate from pyogenic abscesses

[8], [9], [10]

Subdiaphragmatic and subhepatic abscess

Almost completely anehogennoe, clearly delineated, triangular form of formation between the liver and the right dome of the diaphragm can be a right-sided subdiaphragmatic abscess. Subdiaphragmatic abscesses can have different sizes and often are bilateral, so it is also necessary to examine the left sub-diaphragmatic space. When forming a chronic abscess, the contours of the abscess become indistinct: septa and internal sediment can be visualized.

When performing an ultrasound study for fever of unknown origin or fever after surgery, both the right and left sub-diaphragmatic space should be examined.

It is also necessary to examine the posterior parts of the pleural sinuses to exclude the presence of concomitant pleural effusion (which can also be caused by purulent or amoebic liver abscess). It may be useful chest radiography. When a sub-diaphragmatic abscess is detected, it is necessary to examine the liver to exclude the concomitant amoebae or subdiaphragmatic abscess.

Sometimes a subdiaphragmatic abscess can reach the subhepatic space, more often between the liver and the kidney, where it is visualized by the same anechoic or mixed echogenicity structure with internal sediment.

Hematomas of the liver

Ultrasound clearly reveals intrahepatic hematomas, the echogenicity of which can vary from hyper- to hypoechoic. Nevertheless, it may be necessary to have an appropriate history and clinical symptomatology in order to differentiate between hematomas and abscesses.

Subcapsular hematomas can be represented by anechogenous or mixed echogenicity (due to the presence of blood clots) by zones located between the liver capsule and the underlying hepatic parenchyma. The liver contour does not usually change.

Extracapsular hematomas are anechogenous or mixed echogenicity (due to the presence of blood clots) zones located close to the liver, but outside the liver capsule. An echographic picture may look like an extrahepatic abscess.

Any patient with a liver injury can have several intraparenchymal hematomas, subcapsular hematomas, or extrahepatic hematomas. It is necessary to investigate other organs, especially the spleen and kidneys.

Bilomy

The fluid inside or around the liver can be bile arising from a trauma to the biliary tract. According to ultrasound, it is impossible to distinguish between biloba and hematoma.