Abdominal x-ray


An abdominal x-ray is an x-ray of the abdomen. It is sometimes abbreviated to AXR, or KUB.

Indications

In children, abdominal x-ray is indicated in the acute setting:
Yet, CT scan is the best alternative for diagnosing intra-abdominal injury.
For acute abdominal pain in adults, an abdominal x-ray has a low sensitivity and accuracy in general, as well as for specific conditions such as gastrointestinal perforation, bowel obstruction, ingested foreign body, and ureteral stones. Computed tomography, particularly computed tomography after negative abdominal ultrasonography, provides a better workup than projectional abdominal radiography alone. Computed tomography provides an overall better surgical strategy planning, and possibly less unnecessary laparotomies. Abdominal x-ray is therefore not recommended for adults with acute abdominal pain presenting in the emergency department.

Projections

The standard abdominal X-ray protocol is usually a single anteroposterior projection in supine position. Special projections include a PA prone, lateral decubitus, upright AP, and lateral cross-table. A minimal acute obstructive series includes two views: typically, a supine view and an upright view, although a lateral decubitus could be substituted for the upright.
Coverage on the x-ray should include from the top of the Liver to the pubic symphysis. The abdominal organs included on the xray are the liver, spleen, stomach, intestines, pancreas, kidneys, and bladder.

KUB

KUB stands for Kidneys, Ureters, and Bladder. The KUB projection does not necessarily include the diaphragm. The projection includes the entire urinary system, from the pubic symphysis to the superior aspects of the kidneys. The anteroposterior abdomen projection, in contrast, includes both halves of the diaphragm. If the patient is large, more than one film loaded in the Bucky in a "landscape" direction may be used for each projection. This is done to ensure that the majority of bowel can be reviewed.
A KUB is a plain frontal supine radiograph of the abdomen. It is often supplemented by an upright PA view of the chest and a standing view of the abdomen.
Despite its name, a KUB is not typically used to investigate pathology of the kidneys, ureters, or bladder, since these structures are difficult to assess In order to assess these structures radiographically, a technique called an intravenous pyelogram was historically utilized, and today at many institutions CT urography is the technique of choice.
KUB is typically used to investigate gastrointestinal conditions such as a bowel obstruction and gallstones, and can detect the presence of kidney stones. The KUB is often used to diagnose constipation as stool can be seen readily. The KUB is also used to assess positioning of indwelling devices such as ureteric stents and nasogastric tubes. KUB is also done as a scout film for other procedures such as barium enemas.

Gastrointestinal series

An upper gastrointestinal series is where a contrast medium, usually a radiocontrast agent such as barium sulfate barium salt mixed with water, is ingested or instilled into the gastrointestinal tract, and X-rays are used to create radiographs of the regions of interest. The barium enhances the visibility of the relevant parts of the gastrointestinal tract by coating the inside wall of the tract and appearing white on the film.
A lower gastrointestinal series is where radiographs are taken while barium sulfate, a radiocontrast agent, fills the colon via an enema through the rectum. The term barium enema usually refers to a lower gastrointestinal series, although enteroclysis is often called a small bowel barium enema.