The paracolic gutters (also known as paracolic sulci, paracolic recesses) are spaces between the colon and the abdominal wall. Trace/small amounts of free fluid in this region is a normal finding in individuals without symptoms or known abdominal/pelvic disease.
The diaphragm is a thin, dome-shaped muscular structure that is the primary muscle for respiration (breathing), particularly inspiration (breathing in). An elevated hemidiaphragm and diaphragmatic paresis (a condition in which either the right or left side of the diaphragm loses the ability to contract to allow proper inspiration) occurs when one side of the diaphragm (above, at or below) becomes weak from muscular disease or due to injury of the phrenic nerve (the nerve that provides exclusive motor control of the diaphragm and is essential for breathing). Individuals may present with difficulty breathing, but more commonly elevated hemidiaphragm is found on imaging as an incidental finding (found in passing when looking for something else), and individuals are asymptomatic (do not have symptoms).
A paraumbilical hernia occurs when part of the intestine or fat sticks out through an opening in the abdominal muscles with close approximation to the umbilicus (where the umbilical cord passed prior to birth). This creates a soft swelling or bulge near the navel. In adults, paraumbilical hernias are most often acquired due to increased intra-abdominal pressure brought on by obesity, straining with heavy lifting or coughing, or pregnancy.
Lymph nodes are small bean-shaped structures that are part of the body's immune system. The mesentery is the tissue that holds the small intestines. The retroperitoneal lymph nodes drain lymphatic fluid from the abdominopelvic gastrointestinal system as well as the skin, muscles, organs and deep tissues of the posterior abdominal wall. The main symptom for panniculitis (inflammation of subcutaneous fat), if it is acute, is painful or tender bumps called nodules that form in the layer of fat under your skin. Systemic symptoms may also be present and can include fatigue, fever, a general feeling of being unwell (malaise), joint and muscle pain, abdominal pain, nausea, vomiting, and/or weight loss.
A seroma is a collection of serum - the fluid, non-cellular component of blood. This is a common finding after surgery, especially with breast or abdominal procedures.Seromas can sometimes become infected requiring treatment with antibiotics. They can interfere with healing of a surgical site and may require drainage if they are large. However, they do not always need treatment, and smaller seromas often spontaneously resolve after months or years.
The jejunum is the middle part of the small intestine. Sometimes if there is a weak spot in the wall of the intestine, a small bulge (diverticulum) can form. Diverticula usually do not cause symptoms.
