Ultrasound findings in the omental bursa: a short pictorial essay

The omental bursa is a complex and important anatomical region. It serves as a barrier to block pathological processes, but it is also a channel for disease spread in the abdominal cavity. It is a large recess of the peritoneal cavity formed by a double-layered fold of serous peritoneum situated inferiorly to the liver, posteriorly to the lesser omentum and the stomach and anteriorly to the pancreas. Ultrasound (US) has an important role in the study of the omental bursa, as it is generally the first examination to be performed in the presence of abdominal pain. US is inexpensive, widely available and able to identify many of the alterations that may occur in the abdomen. However, US findings are often varied and unspecific, ranging from fluid collections to diffuse infiltration. Familiarity with the various diseases that may affect the omental bursa is essential in order to be able to identify them during US examination of the abdomen. US imaging is useful in the follow-up after treatment and to guide drainage of fluid collections.