Ultrasound signs of spleen pathology

There are no absolute criteria for determining the size of the spleen during an ultrasound examination; if it is normal, it is slightly larger or approximately the same size as the left kidney.

Enlarged spleen/splenomegaly

The length should not exceed 15 cm along the long axis.

A chronically enlarged spleen can rotate and displace the left kidney, causing a decrease in the anteroposterior dimension and width of the kidney.

Splenomegaly with homogeneous echotexture

May occur when:

1. Tropical splenomegaly, which includes idiopathic splenomegaly, malaria, trypanosomiasis, leishmaniasis and schistosomiasis.
2. Sickle cell anemia (without infarction).
3. Portal hypertension.
4. Leukemia.
5. Metabolic diseases.
6. Lymphoma (may also contain hypoechoic structures).
7. Infectious diseases such as rubella and infectious mononucleosis.

If splenomegaly is detected, determine the size of the liver and its echogenicity, also examine the splenic and portal veins, the inferior vena cava, hepatic veins, and the mesenteric vein for dilation. It is necessary to examine the area of the splenic hilum to identify tubular structures in varicose veins.

Abnormal echostructure of the spleen with or without splenomegaly

Well-demarcated cystic lesions

If there are clearly demarcated anechoic formations with distal acoustic enhancement, it is necessary to differentiate:

1. Polycystic disease (there may be multiple cysts). Examine the liver or pancreas for cysts.
2. Congenital cysts. They are usually solitary and may contain internal echostructures as a result of hemorrhage.
3. Echinococcal (parasitic) cysts. They are usually clearly demarcated, have a double contour (the pericystic wall and the cyst wall) and often have septa. A clear enhancement of the posterior wall is determined and there is often a variable thickness of the cyst wall. However, parasitic cysts can be presented as rounded formations with an uneven contour, heterogeneous echostructure, simulating an abscess. Cysts can be hypoechoic with a small number of various internal echostructures or hyperechoic and solid without any acoustic shadow: various combinations of such types of structures are found. The cyst walls can be collapsed or prolapsed, floating structures can be observed inside the cysts, even a cyst within a cyst can be visualized (this sign is pathognomonic for a parasitic cyst). Calcification in the cyst wall can occur, there can be "sand" in the cavity, located in the lowest place. Perform a full abdominal scan and chest x-ray. Parasitic cysts are often multiple, but their echotexture may vary, and cysts in the liver do not necessarily look the same as cysts in the spleen.
4. Hematoma.

If there is an enlarged spleen and a history of trauma, an ultrasound examination of the spleen should be performed to rule out damage to it.

A formation in the spleen with a smooth but unclear outline

Scan in different projections.

1. A hypoechoic cystic area with irregular borders, usually with sediment, associated with splenomegaly and local tenderness is most likely a splenic abscess. Examine the liver for other abscesses.

With adequate treatment, the abscess may resolve or enlarge and become almost anechoic, but will no longer be painful.

2. Similar cystic structures, large in size and containing fluid, may be abscesses resulting from infarction in sickle cell anemia. Amebic abscesses are rare in the spleen: bacterial abscesses are more common.

Splenic vein

Normal dimensions of the splenic vein do not exclude the possibility of portal hypertension.

Splenic vein dilation

If the splenic vein appears large and has a diameter greater than 10 mm in all phases of the respiratory cycle, portal hypertension may be suspected. If the portal vein has a diameter greater than 13 mm and does not change size during respiration, the likelihood of portal hypertension is very high.

Splenic masses with or without splenomegaly

Splenic masses may be single or multiple, with clear or fuzzy margins. Lymphoma is the most common cause of splenic masses, and these masses are usually hypoechoic. Malignant tumors, primary or metastatic, are rare in the spleen and may be hyper- or hypoechoic. In the presence of necrosis, a cystic-solid internal structure resembling an abscess may appear. Infectious diseases such as tuberculosis or histoplasmosis may produce diffuse granulomatosis, which is represented by hyperechoic masses, sometimes producing an acoustic shadow due to calcification. Hematoma must be excluded.

If there is a depression of the spleen contour near the formation, this formation is probably an old hematoma or a scar from an injury. On the other hand, it may be an old infarction (for example, in sickle cell anemia).

When a formation is detected in the spleen, it is necessary to exclude fresh damage to it, especially if there is splenomegaly.

Splenic abscess: a cystic structure with an irregular outline, hypoechoic or mixed echostructure.

Fever (usually of unknown origin)

If possible, check the white blood cell count and white blood cell count. Start with longitudinal sections.

An anechoic or mixed echogenic mass located near the spleen, subdiaphragmatic, anterior to the spleen but limited to the left dome of the diaphragm, may be a subdiaphragmatic abscess. Diaphragmatic mobility may be decreased. Also scan the right subdiaphragmatic region to rule out fluid on the right. Also scan the entire abdomen, including the pelvis, to rule out fluid elsewhere. Scan the lower and lateral left chest to rule out pleural fluid, which may occasionally be visualized through the spleen. A chest radiograph may be helpful.

Injury

The examination involves precise contouring of the spleen to see any area of local enlargement, as well as scanning the abdominal area to rule out the presence of free fluid in the abdominal cavity. If the patient's condition does not improve, repeat the examination in a few days.

1. If there is free fluid in the abdominal cavity or fluid in the subdiaphragmatic space and an uneven contour of the spleen, then a rupture or injury of the spleen may occur.
2. Visualization of an anechoic or mixed echogenicity zone in combination with diffuse or localized enlargement of the spleen suggests the presence of a subcapsular hematoma. Carefully search for free fluid in the abdominal cavity.
3. An anechoic or mixed echogenicity structure with an irregular outline within the spleen suggests the presence of an acute hematoma. An additional spleen may have the same echographic appearance.
4. A highly echogenic lesion in the spleen may be an old calcified hematoma, producing bright hyperechoic structures with an acoustic shadow. A hemangioma may have a similar echographic picture.
5. An anechoic or mixed echogenicity formation with an irregular outline may be a traumatic cyst or a damaged parasitic cyst.

If splenomegaly, persistent anemia, or free fluid in the abdominal cavity are detected, in the presence of a history of abdominal trauma within the last 10 days, it is necessary to think about splenic injury.