CT of the stomach and duodenum.

CT has become an important tool in the diagnosis and management of diseases that affect the stomach and duodenum. By depicting the bowel lumen, wall, and extramural structures, CT can provide unique information that complements standard air contrast radiography and endoscopy. Proper scanning methods and knowledge of normal anatomy are necessary for optimal results. We utilize the gas contrast technique for organ-specific examination in patients with known or suspected gastroduodenal disease. Gastric adenocarcinoma is an important indication for CT evaluation. Unfortunately, early hopes that CT could accurately stage gastric cancer have not been realized. CT is not as accurate as laparotomy in staging early gastric cancer, primarily owing to its inability to detect small peritoneal implants, diagnose metastases in normal-sized lymph perigastric nodes, and predict pancreatic invasion. Nevertheless, CT retains an important role in depicting gross metastatic disease and guiding percutaneous biopsy, particularly in patients who are deemed poor surgical candidates or have undergone prior gastric resection. A variety of conditions other than primary gastric adenocarcinoma produce recognizable abnormalities on CT. Gastric lipoma, leiomyosarcoma, and varices have a distinctive appearance. Others, including gastritis and uncomplicated peptic ulcer, produce nonspecific gastric wall thickening. Endoscopic correlation and biopsy are required for specific diagnosis in these cases. The duodenum, by virtue of its location in the anterior pararenal compartment of the retroperitoneum, may be involved by numerous benign and malignant conditions. In blunt trauma, complicated pancreatitis, and peptic ulcer disease, as well as primary and metastatic malignancy, CT can provide data that may alter patient management.