Polypoid lesions at the anorectal junction: barium enema findings

Double-contrast barium enema technique

During a double-contrast barium enema the radiologist interacts with the patient, the controls of the fluoroscope, and the image on the television monitor. The radiologist paints an image of the colon; the barium is the paint, the colon is the canvas. The radiologist manipulates the barium pool, the air column, and the patient to create images. Although the radiologist may have a plan going into the examination, the game plan is altered by the patient's ability to tolerate and perform the study, the length of the colon, and pathology encountered. If the radiologist understands the goals to be achieved, the studied can be tailored to fit what is happening in the fluoroscopic suite.

Diagnosis of colorectal neoplasms at double-contrast barium enema examination

The double-contrast barium enema examination has been recognized as an option for colorectal cancer screening in Americans with average risk who are greater than 50 years of age. The purpose of this article is to review the principles for diagnosing colorectal neoplasms on double-contrast images and the spectrum of findings associated with these lesions. Colonic polyps can be sessile or pedunculated; their appearance depends on whether they are located on the dependent or nondependent wall of the bowel. Villous tumors may be flat, lobulated lesions, also known as "carpet" lesions, that are characterized by a finely nodular or reticular surface pattern, without a discrete mass. Colonic carcinomas may manifest as plaquelike, polypoid, semiannular ("saddle") or annular lesions. Colonic neoplasms sometimes are more difficult to detect in the region of the ileocecal valve or the distal rectum or in patients with severe diverticulosis. Careful double-contrast technique and meticulous scrutiny of the images therefore are required to optimize detection of these lesions.

Double-contrast barium enema examination technique

This review article presents the principles for performing a safe, comfortable, and accurate double-contrast barium enema examination. The procedure is a flexible examination in which the fluoroscopist interacts with the patient, the controls of the fluoroscope, and the image on the television monitor. During a double-contrast examination, images of the colon are created by manipulating the patient, the barium pool, and the amount of air insufflated into the rectum. Fluoroscopy is essential for guiding the radiologist to obtain spot images with adequate technical factors. The fluoroscopist analyzes the luminal contour, the barium-coated mucosal surface en face, and the barium pool to detect abnormalities in the colon. With careful technique, a high-quality examination can be performed in most patients.