Abdominal X-rays

(Flat Plate of the Abdomen, Abdominal Radiography, KUB [Kidneys, Ureters, Bladder] X-ray)

Procedure overview

X-rays use invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs on film. Standard X-rays are performed for many reasons, including diagnosing tumors or bone injuries.

X-rays are made by using external radiation to produce images of the body, its organs, and other internal structures for diagnostic purposes. X-rays pass through body tissues onto specially treated plates (similar to camera film) and a "negative" type picture is made (the more solid a structure is, the whiter it appears on the film).

X-rays of the abdomen may be performed to assess the abdominal area for causes of abdominal pain, to locate swallowed foreign objects, or to locate an obstruction or perforation in the abdomen.

Abdominal X-rays may be taken with the patient in the upright position (erect abdominal view), lying flat with the exposure made from above the patient (supine abdominal view), or lying flat with the exposure made from the side of the patient (cross-table lateral view). The left side-lying position (left lateral decubitus view) may be used for patients who cannot stand erect.

When two or more of these views are taken while trying to locate a site of intestinal or abdominal obstruction, the set of films may be referred to as an obstruction series. The supine abdominal view may be referred to as a KUB (kidney, ureter, and bladder) film even when examining the gastrointestinal (GI) organs, because the X-ray study used to examine the kidneys, ureter, and bladder is very similar to the supine abdominal view.

Other related procedures that may be used to diagnose conditions of the abdomen include computed tomography (CT scan) of the abdomen, abdominal ultrasound, abdominal angiogram, or nuclear scans of specific abdominal organs such as the gallbladder, liver, or pancreas. Please see these procedures for additional information.

Reasons for the procedure

Abdominal X-rays may be performed to diagnose causes of abdominal pain, such as masses, perforations, or obstruction. Abdominal X-rays may be performed prior to other procedures that evaluate the gastrointestinal (GI) tract or urinary tract, such as an abdominal CT scan and renal procedures.

Basic information regarding the size, shape, and position of abdominal organs may be obtained with abdominal X-rays. The presence of calcifications (stones) in the gallbladder, kidneys, or ureters may be noted. Calcification of the aorta may also be seen with an abdominal X-ray.

There may be other reasons for your doctor to recommend an abdominal X-ray.

Risks of the procedure

You may want to ask your doctor about the amount of radiation used during the procedure and the risks related to your particular situation. It is a good idea to keep a record of your past history of radiation exposure, such as previous scans and other types of X-rays, so that you can inform your doctor. Risks associated with radiation exposure may be related to the cumulative number of X-ray examinations and/or treatments over a long period of time.

If you are pregnant or suspect you may be pregnant, you should notify your health care provider. Radiation exposure during pregnancy may lead to birth defects.

There may be other risks depending on your specific medical condition. Be sure to discuss any concerns with your doctor prior to the procedure.

Recent barium X-rays of the abdomen may interfere with the accuracy of an abdominal X-ray.

Before the procedure

  • Your doctor will explain the procedure to you and offer you the opportunity to ask any questions that you might have about the procedure.

  • Generally, no prior preparation, such as fasting or sedation, is required.

  • Notify the radiologic technologist if you are pregnant or suspect you may be pregnant.

  • Notify your doctor and radiologic technologist if you have taken a medication that contains bismuth, such as Pepto-Bismol, in the past four days. Medications that contain bismuth may interfere with testing procedures.

  • Based on your medical condition, your doctor may request other specific preparation.

During the procedure

Abdominal X-rays may be performed on an outpatient basis or as part of your stay in a hospital. Procedures may vary depending on your condition and your doctor's practices.

Generally, abdominal X-rays follow this process:

  1. You will be asked to remove any clothing, jewelry, or other objects that might interfere with the procedure.

  2. If you are asked to remove clothing, you will be given a gown to wear.

  3. You will be positioned in a manner that carefully places the part of the abdomen to be X-rayed between the X-ray machine and a cassette containing the X-ray film. You may be asked to stand erect, to lie flat on a table, or to lie on your side on a table, depending on the X-ray view your doctor has requested. You may have X-rays taken from more than one position.

  4. Body parts not being imaged may be covered with a lead apron (shield) to avoid exposure to the X-rays.

  5. Once you are positioned, you will be asked to hold still for a few moments while the X-ray exposure is made. You may be asked to hold your breath at various times during the procedure.

  6. It is extremely important to remain completely still while the exposure is made, as any movement may distort the image and even require another X-ray to be done to obtain a clear image of the body part in question.

  7. The X-ray beam is then focused on the area to be photographed.

  8. The radiologic technologist steps behind a protective window while the image is taken.

While the X-ray procedure itself causes no pain, the manipulation of the body part being examined may cause some discomfort or pain, particularly in the case of a recent injury or invasive procedure such as surgery. The radiologic technologist will use all possible comfort measures and complete the procedure as quickly as possible to minimize any discomfort or pain.

After the procedure

Generally, there is no special type of care following abdominal X-rays. However, your doctor may give you additional or alternate instructions after the procedure, depending on your particular situation.

Online resources

The content provided here is for informational purposes only, and was not designed to diagnose or treat a health problem or disease, or replace the professional medical advice you receive from your doctor. Please consult your health care provider with any questions or concerns you may have regarding your condition.

This page contains links to other websites with information about this procedure and related health conditions. We hope you find these sites helpful, but please remember we do not control or endorse the information presented on these websites, nor do these sites endorse the information contained here.

American Cancer Society

American College of Gastroenterology

National Cancer Institute (NCI)

National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

National Institutes of Health (NIH)

National Library of Medicine