Soft-tissue structures in the pelvic area are difficult to visualize without using contrast media.
Contrast X-ray examinations are used to diagnose soft-tissue pathology. Unlike bones, soft tissue offers little image contrast, which makes irregularities caused by trauma or illness difficult to visualize. During a contrast X-ray examination, contrast media is administered, typically via injection, ingestion or inhalation into the body part to be examined. The patient is then radiographed (X-rayed), and a radiologist (physician specializing in diagnostic imaging) interprets the images to determine a diagnosis.
Barium Sulfate Exams
Common contrast examinations of the gastrointestinal system include the esophagram (examination of the esophagus), upper GI (examination of the esophagus, stomach and small intestine) and the lower GI (commonly misnamed examination of the large intestine). Contrast media (typically barium sulfate in suspension) is administered via ingestion or through a feeding tube for the upper GI and via enema for the lower GI. Body cavities are sometimes insufflated with carbon dioxide or room air following administration of barium sulfate for a double contrast study to better evaluate mucosal tissue linings.
Iodinated Contrast Exams
Iodine-based contrast media is used to evaluate most other soft-tissue cavities and vessels in the body. It is readily absorbed into the bloodstream and excreted through the urinary system. Examinations for which iodinated contrast media is used include those to visualize the hepatobiliary system (liver, pancreas, gall bladder and biliary ducts), urinary system (kidneys, ureters, bladder and urethra), the spinal cord, female reproductive organs (vagina, uterus and fallopian tubes) and vascular system (arteries, veins and lymphatic system).
Alternative Contrast Imaging Modalities
Through computer image contrast enhancement and image receptor improvement, computerized tomography (CAT scan), magnetic resonance imaging (MRI) and sonography have replaced contrast X-ray examinations for evaluating many body parts. Head CAT scans or MRI exams offer much more valuable diagnostic information about brain irregularities caused by trauma or disease than could be determined by encephalography (contrast X-ray examination of the head). Sonographic and nuclear medicine (using radioisotopes) exams have replaced many of the hepatobiliary X-ray contrast examinations because they provide more diagnostic information. Many thoracic, abdominal and pelvic X-ray examinations are now done with advanced imaging modalities for the same reason.
Tags: contrast media, X-ray examinations, barium sulfate, caused trauma, contrast examinations, contrast media used
