RADIOLOGIC techniques play an important role in the diagnostic evaluation for carcinoma of the colon. It is essential, therefore, to understand these methods thoroughly.
PLAIN FILM EXAMINATION
Approximately 13% to 25% of patients with carcinoma of the colon are first encountered with partial or complete obstruction of the bowel. Carcinoma of the colon, rectum, and anus is the most common cause of large-bowel obstruction.1 Plain film examination of the abdomen, with supine and erect views, can provide a strong presumptive diagnosis of carcinoma of the colon when complete obstruction is present. Exploratory laparotomy is commonly performed without further radiologic studies, although a barium enema examination would localize the site of obstruction accurately.
BARIUM ENEMA EXAMINATION
For lesions beyond the reach of the sigmoidoscope, the barium enema examination is often the single source of objective information on which important clinical decisions are based.The common roentgenographic appearances of carcinoma of