DefinitionBarium enema is a special x-ray of the large intestine, which includes the colon and rectum.Alternative NamesLower gastrointestinal series; Lower GI seriesHow the test is performedThis test may be done in an office or a hospital radiology department. It is done after the colon is completely empty. Your doctor will give you instructions how to do this.You lie flat on your back on the x-ray table and a preliminary x-ray is taken. You will then be told to lie on your side. The health care provider will gently insert a well-lubricated tube (enema tube) into your rectum. The tube is connected to a bag that holds a liquid containing barium sulfate. It is placed in the rectum. The liquid is a type of contrast. Contrast highlights specific areas in the body, creating a clearer image. The