Comprehension: Small Intestine
An axial CT scan at the level of the body of L4 is shown. The small intestine has been opacified with swallowed barium contrast material which has not yet reached the colon. Sections of the colon can be seen filled with air and fecal material. Intravenous contrast material has outlined the proximal common iliac arteries as well as the inferior vena cava to the patient's right of these arteries. Note the prominent fat about the psoas muscles. As indicated above, fat, with a different x-ray density, appears dark as it surrounds the more radiopaque psoas muscles. The muscles of the abdominal wall are also seen.
