Colonic Obstruction Mechanical large bowel obstruction is four to five times less common than small bowel obstruction and differs significantly in terms of cause ( Table 46.1 ), pathophysiology, therapy, and prognosis. Colon obstruction is most often the result of…
This chapter discusses a variety of benign and malignant tumors of the colon as separate entities. Although these tumors are associated with a wide range of clinical and radiologic manifestations, they may have typical features on imaging studies that suggest…
Abnormalities of Small Bowel Development in Adults MECKEL’S DIVERTICULUM During embryologic development, the yolk sac is connected to the midgut by the omphalomesenteric duct, which is later obliterated during the seventh to eighth weeks of embryogenesis. Persistence of the entire…
In patients with known or suspected small bowel obstruction (SBO), the radiologist is called on to answer the following questions: Is the bowel obstructed? If so, what is the level of obstruction? What is the cause of obstruction? What is…
Anatomic Classification of Malabsorption Carbohydrate digestion requires a functioning pancreas and small bowel brush border enzymes. Normal protein digestion requires adequate gastric and pancreatic function and small bowel brush border enzymes. Fat digestion requires normal hepatic, biliary, exocrine, pancreatic, and…
The radiologist usually encounters infectious disease of the small intestine during the workup of patients with acute abdominal pain or diarrhea or with chronic diarrhea, malabsorption, and weight loss. If computed tomography (CT) reveals thickened ileal folds or regional mesenteric…
Normal Small Intestine The small intestine is extremely tortuous, beginning at the pylorus and extending about 11 feet in the living human from the pylorus to the ileocecal valve. Intestinal length is extremely variable, depending on neuromuscular tone and vascular…
General Principles Radiologic evaluation of the postoperative esophagus requires an understanding of the operative procedures and normal postoperative findings. Radiographic studies are performed in these patients for three general purposes: (1) to define the postoperative anatomy and establish a baseline;…
Functional Abnormalities AGING Age-related change in the muscles, tendons, ligaments, cartilages, and nerves that participate in pharyngeal function may alter swallowing dynamics, causing a swallowing disorder. The type of normal swallowing in young patients is found in only about 15%…
The pharynx is the crossroads of respiration, speech, and swallowing. During respiration, the pharynx is an active conduit for the passage of air from the nasopharynx to the laryngeal aditus. During speech, the pharynx functions as a resonating chamber, changing…