Etiology Vascular lesions of the colon are an important medical problem and have now been recognized as a significant cause of gastrointestinal bleeding. They can be solitary or multifocal, benign or malignant, or associated with a syndrome or systemic disorder.…
Etiology Colonic inflammation may be caused by numerous processes and is typically thought of as colitis. Some inflammatory conditions of the colon such as diverticulitis and epiploic appendagitis also represent inflammatory lesions of the colon and, on occasion, may be…
Technical Aspects Colorectal cancer is the second cause of cancer deaths in the United States, second only to lung cancer in men and breast cancer in women. Colorectal cancer screening can be used to identify adenomatous polyps, the precursor lesion…
Conventional Imaging Technical Aspects Before cross-sectional imaging, the double-contrast enema was the foremost radiologic method for detection of colonic mucosal lesions and precancerous polyps. Diagnostic high-quality double-contrast barium enema examination is an art, requiring skillful maneuvering of the patient and…
Small bowel neoplasms remain a diagnostic challenge for radiologists and clinicians. The small bowel represents 75% of the total length of the gastrointestinal tract and more than 90% of the mucosal surface, but less than 2% of all gastrointestinal malignancies…
Normal intestinal wall thickness depends on the degree of bowel distention and the imaging modality. The normal jejunum wall thickness measures approximately 2 mm and the ileum 1 mm on enteroclysis. On computed tomography (CT), 3 mm is accepted as the upper limit…
Etiology Acute mesenteric ischemia of the small bowel has four major causes: (1) arterial embolism, (2) arterial thrombosis, (3) nonocclusive mesenteric ischemia, and (4) mesenteric venous thrombosis ( Table 26-1 ). Less common causes include aortic dissection, spontaneous dissection of…
Small Bowel Obstruction: General Considerations Etiology Small bowel obstruction (SBO) is a common manifestation, and appropriate management continues to be a clinical challenge. The morbidity and mortality associated with acute SBO continue to be significant; however, there has been a…
Traditional evaluation of the small bowel involved small bowel follow-though (SBFT) or enteroclysis, which provide excellent survey of the small bowel but are insensitive for subtle bowel pathologic processes and extraluminal abdominal findings. Within the last decade, as a result…
Technical Aspects Radionuclide gastric emptying studies (scintigraphy) remain the most widely used method for evaluation of gastric function. Radiopharmaceuticals Gastric emptying scintigraphy is most commonly performed with technetium-99m ( 99m Tc) sulfur colloid dispersed in a solid and/or liquid bolus.…