A stomach X-ray, also referred to as an abdominal X-ray or a KUB (kidneys, ureters, and bladder) X-ray, is a common diagnostic tool that uses a small amount of radiation to create images of the inside of your abdomen. This quick and non-invasive procedure helps medical professionals visualize organs like the stomach, liver, spleen, and intestines, along with the bones of the lower spine. The X-ray machine sends a beam of radiation through the body, and the resulting image is recorded on a special film or computer screen, appearing in shades of black and white. Denser structures, such as bones, absorb more radiation and appear white, while softer tissues allow more radiation to pass through, appearing darker. This makes it a useful initial step in diagnosing various abdominal issues, often performed to investigate symptoms like unexplained pain, nausea, or vomiting.
What a Stomach X-ray Can Show
A stomach X-ray can reveal abnormalities based on differences in tissue density. It is effective at identifying unusual gas patterns within the intestines. For instance, excessive gas or dilated loops of bowel can suggest conditions like an ileus (a temporary lack of normal muscle contractions in the intestines) or a bowel obstruction. Free air under the diaphragm, appearing as gas outside the intestines, indicates a perforation or hole in the stomach or intestines.
The X-ray can also detect foreign bodies that have been swallowed. Objects made of metal, like coins or certain toys, are dense enough to block X-rays and appear clearly on the image. Dense food items might also be visible.
Calcifications, or hardened deposits of calcium, are another type of finding readily seen on an X-ray. These can include kidney stones, bladder stones, or some gallstones. Calcified masses or areas of chronic inflammation, such as those sometimes seen in chronic pancreatitis, can also appear as stippled or rounded calcifications.
Stomach X-rays are used to confirm the correct placement of various medical devices within the abdomen. This includes feeding tubes, catheters, and surgical clips, which are designed to be radiopaque (visible on X-ray). X-rays also help check for any related complications, such as kinking or migration.
What a Stomach X-ray Cannot Show
Despite its utility, a stomach X-ray has limitations, particularly concerning soft tissues. X-rays produce two-dimensional images and offer poor contrast resolution for many internal organs and soft tissue structures. This means that subtle details within organs like the liver, spleen, or pancreas are not clearly visible.
An X-ray cannot reliably show detailed inflammation, such as gastritis, appendicitis, or diverticulitis, because these conditions primarily involve soft tissue changes that do not significantly alter X-ray absorption. Ulcers or erosions in the stomach lining are too subtle to be seen on a standard X-ray. Most tumors or masses are also not detectable unless very large or calcified, as their density is often similar to surrounding soft tissues. Internal bleeding, early organ pathology, or the precise cause of many types of abdominal pain are beyond the scope of a stomach X-ray.
When Other Imaging is Needed
A stomach X-ray often serves as a preliminary diagnostic step. If the initial X-ray is inconclusive or more detailed information is required, other imaging modalities are employed. These advanced tests offer different perspectives and capabilities that an X-ray lacks, especially concerning soft tissue evaluation.
When a stomach X-ray is insufficient, other imaging modalities are used:
- Computed Tomography (CT) scan: Provides detailed cross-sectional views of the abdomen, offering superior soft tissue contrast for precise localization of inflammation, tumors, and organ injuries.
- Ultrasound: Uses sound waves to create real-time images, useful for assessing fluid collections, gallbladder issues like gallstones, appendicitis, and general organ assessment without ionizing radiation.
- Magnetic Resonance Imaging (MRI): Utilizes powerful magnets and radio waves to produce highly detailed images of soft tissues, nerves, and blood vessels, suitable for complex cases or specific organ pathologies.
- Endoscopy (e.g., EGD): Involves inserting a flexible tube with a camera directly into the digestive tract to visually inspect the stomach lining, identify ulcers, or perform biopsies.
These varied techniques complement the X-ray, providing a comprehensive diagnostic approach when needed.