How to detect abdominal masses in children with ultrasound

Children's health issues have always been a concern for parents. Abdominal masses refer to enlarged, protruding or bulging areas in the child's abdomen, which may cause pain, discomfort or other symptoms, making many parents worried. With the continuous development of medical technology in my country, we can use ultrasound examination to examine and diagnose children's abdominal masses. This article will take you to learn about ultrasound examination knowledge of children's abdominal masses, so hurry up and learn it!

1. What are the abdominal masses in children?

1.1 Intestinal duplication cyst

As children develop, abnormalities in the intestines lead to the formation of cystic structures, which can usually be observed in infancy and manifest as an abdominal mass.

1.2 Mesenteric or omental cyst

Mesenteric or omental cysts are cystic dilated areas that form on the mesentery or omentum. This disease is usually congenital, that is, it has already formed during the embryonic development stage of the child. Mesenteric cysts may be caused by abnormal structures, duct occlusion, maldevelopment, etc. on the mesentery and omentum. These cysts can be single or multiple and vary in size. In most cases, mesenteric cysts are asymptomatic. Sometimes children may experience abdominal discomfort, distension, or a palpable mass. A few cysts may lead to torsion or intestinal obstruction and require medical attention.

1.3 Pancreatic pseudocyst

Pancreatic pseudocyst is a cystic lesion caused by dilation of the pancreatic lumen due to pancreatitis or pancreatic injury. It is rare in children, but still requires attention.

1.4 Cystic teratoma

Cystic teratoma is a rare disease that is composed of a mixture of multiple germ layer tissue types, including cysts, fat, bone, hair, etc., and is usually discovered after birth or in infancy.

1.5 Urinary cyst

Urocysts are cystic dilatations caused by abnormalities of the urinary tract system in the abdominal and pelvic regions. Common urocysts in children are hydronephrosis and hydroureter.

1.6 Ovarian Cyst

Ovarian cysts are common cystic masses in the female reproductive system, usually fluid-filled cysts in the ovaries, and are occasionally found in children.

2. How does ultrasound identify abdominal masses in children?

2.1 Ultrasound manifestations of intestinal duplication cysts

Intestinal duplication cyst is a common abdominal mass in children. It can be divided into extraluminal, intraluminal and tubular types. In ultrasound images, the extraluminal intestinal duplication cyst can clearly see the hyperechoic mucosal layer and hypoechoic muscle layer. There are round or quasi-round cysts in the abdominal cavity that are closely adjacent to the intestine or stomach, with clear boundaries and slightly thick cyst walls, similar to the intestinal wall. High-frequency ultrasound can observe the high-weak-high three-layer structure of the cyst wall. The fluid in the cyst has good sound permeability and may show no echo or debris-like impurity echoes. It is mostly single-chamber type, and occasionally septa can be seen. In addition, ultrasound can also show blood flow signals in the cyst wall, and the disease may cause intussusception. Intraluminal intestinal duplication cysts are relatively rare, mainly occurring in the ileocecal region. Cystic structures can be seen in the intestinal cavity, and the proximal intestine may have abnormal expansion and effusion. Tubular intestinal duplication cysts appear as atrophic intestinal mucosal thickening on ultrasound.

2.2 Mesenteric cyst and omental cyst

Mesenteric cysts appear as irregular, multi-chambered, cystic, anechoic masses between the intestinal tubes in ultrasound images. The cyst wall is thin and has low tension. When secondary bleeding occurs in the cyst, small dot-like echoes can be seen in the cyst. In addition, if the cyst undergoes secondary torsion, the root of the mesentery will appear spiral, accompanied by the appearance of intestinal obstruction. Omental cysts are closely attached to the anterior abdominal wall and cover the front of the intestinal tube. They usually appear as cystic masses with multiple septa and low tension. In ultrasound images, it can be observed that the intestinal tube behind the cyst is compressed and moved backward. There is also a special type of mesenteric cyst, which is composed of countless small cystic cavities. Most of the lesions are solid and medium echo, and only a small number of small honeycomb cysts can be seen at the edge. This type of cyst is easily misdiagnosed as a solid mesenteric tumor. In ultrasound examination, there is no obvious blood flow signal in the cyst wall and septa of mesenteric cysts and omental cysts.

2.3 Choledochal cyst

Choledochal cyst is a rare biliary disease. In ultrasound images, it is usually found near the pancreatic head and gastric antrum, appearing as a cystic dilated structure, usually round or oval in shape. The cyst is located in the liver and is connected to the bile duct along its trajectory. The cyst wall of the choledochal cyst is relatively thin, generally not exceeding 2 mm in thickness. The interior of the cyst usually presents as an obvious anechoic area, indicating that the cyst is filled with fluid. Sometimes small dot-like echoes can be seen inside the cyst, indicating that there may be bleeding, necrosis, etc. in the cyst. Some children with choledochal cysts also have gallbladder cysts, and similar cystic dilated structures can be observed.

1.4 Pancreatic pseudocyst

Pancreatic pseudocysts appear as local or overall cystic dilatation areas of the pancreas in ultrasound images. The shape of the cyst may be irregular, presenting an oval, irregular shape, or multi-chambered septa. The cyst wall of a pancreatic pseudocyst is usually thin, not exceeding 2 mm. The interior of the cyst presents an echo-free or hypoechoic area. Vascular structures can sometimes be observed in and around the cyst wall of a pancreatic pseudocyst, such as vascular shadows in the cyst wall or compression of blood vessels around the cyst. At the same time, the presence of a cyst may cause compression and displacement of surrounding structures, such as dilatation of the adjacent pancreatic duct and bile duct.

1.5 Cystic embryonal tumor

In ultrasound images, cystic embryonal tumors present some characteristic manifestations. First, cystic embryonal tumors appear as one or more cystic dilated structures, in which the cyst wall and the contents inside the cyst can be diverse. The cyst may contain fluid, fat, bone, hair, etc., and high-echoic fat tissue can be seen. The cyst wall often appears as a relatively thick structure in ultrasound, and internal partitions can sometimes be observed. At the same time, there may be vascular structures around the cyst, in which blood flow signals can be seen. This special type of tumor may also cause compression and displacement of blood vessels, nerves, or other organs.

1.6 Urinary cyst

Urocysts are characterized by one or more cystic dilated structures on ultrasound. These cysts are usually located in the abdominal and pelvic regions and are associated with the urinary tract. Urocysts generally have thin walls and good acoustic permeability to the fluid inside, so they appear to have no normal echoes or only a few small echo points on ultrasound. Usually, urocysts are unilocular and may occasionally have septa. Blood flow signals can be observed around the cyst wall on ultrasound images. It is worth noting that the specific ultrasound appearance of urocysts may vary depending on the size, location, and composition of the cyst.

1.7 Ovarian Cyst

Ovarian cysts in children may be located anywhere in the abdominal cavity, appearing as one or more cystic dilated structures with unclear cyst boundaries and stratified changes of liquid debris inside the cyst, which changes with the child's body position. Calcified blood clots or good sound permeability can be seen inside. Ovarian cysts are generally unilocular, with blood flow signals around the cyst, and are common in newborns.

The above is the relevant knowledge about ultrasound examination of abdominal masses in children. Ultrasound examination plays an important role in the evaluation, diagnosis and treatment of abdominal masses in children. It can help doctors understand the characteristics, location, internal structure and relationship of cysts with surrounding tissues, thus assisting diagnosis and formulating appropriate treatment plans. However, it should be noted that the specific ultrasound manifestations may vary due to individual differences and other factors, and specific judgments should be made based on actual ultrasound images.