| Abdominal x-ray | |
|---|---|
 | |
| ICD-9-CM | 87.5,87.9,88.0-88.1 |
| MedlinePlus | 003815 |
Anabdominal x-ray is anx-ray of theabdomen. It is sometimes abbreviated to AXR, orKUB (forkidneys,ureters, andurinary bladder).
In adults, abdominal X-rays have a very low specificity and cannot rule out suspected obstruction, injury or disease reliably.CT scan provides an overall better diagnosis, allows surgical strategy planning, and possibly fewer unnecessary laparotomies. Abdominal x-ray is therefore not recommended for adults with acute abdominal pain presenting in the emergency department.[1]
In children, abdominal x-ray is indicated in the acute setting:
In trauma,CT scan is the best alternative for diagnosing intra-abdominal injury.[2]
The standard abdominal X-ray protocol is usually a single anteroposterior projection insupine position.[3] Special projections include a PA prone, lateral decubitus, upright AP, and lateral cross-table (with the patient supine). A minimal acute obstructive series (for the purpose of ruling outsmall bowel obstruction) includes two views: typically, a supine view and an upright view (which are sufficient to detect air-fluid levels), although a lateral decubitus could be substituted for the upright.
Coverage on the x-ray should include from the top of the Liver (ordiaphragm) to thepubic symphysis. The abdominal organs included on the xray are theliver,spleen,stomach,intestines,pancreas,kidneys, andbladder.
KUB stands forKidneys,Ureters, andBladder. The KUB projection does not necessarily include the diaphragm. The projection includes the entire urinary system, from thepubic symphysis to the superior aspects of the kidneys. The anteroposterior (AP) abdomen projection, in contrast, includes both halves of the diaphragm.[4][5] 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 (to rule out air under the diaphragm or thoracic etiologies presenting as abdominal complaints) and a standing view of the abdomen (to differentiate obstruction from ileus by examining gastrointestinal air/water levels).
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 (for example, the kidneys may not be visible due to overlying bowel gas.) In order to assess these structures radiographically, a technique called anintravenous pyelogram was historically utilized, and today at many institutions CT urography is the technique of choice.[6]
KUB is typically used to investigate gastrointestinal conditions such as a bowel obstruction andgallstones, and can detect the presence ofkidney 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.
Anupper gastrointestinal series is where acontrast medium, usually aradiocontrast agent such asbarium 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.
Alower gastrointestinal series is where radiographs are taken whilebarium sulfate, aradiocontrast agent, fills the colon via anenema through therectum. The termbarium enema usually refers to a lower gastrointestinal series, although enteroclysis (anupper gastrointestinal series) is often called a small bowel barium enema.
