We reviewed the sonographic findings in four patients with afferent loop obstruction from tumor of the gastric stump. All had undergone partial gastrectomy with Billroth type II gastrojejunostomy. The obstructed afferent loop was visible in all cases as a distended fluid-filled segment with multi-layered wall and few mucosal folds. Its course could be traced from the region of the hepatic hilum to the gastric stump. In two patients, the relationships between the loop and the mesenteric vessels, aorta and inferior vena cava allowed us to recognize it as postoperative duodenum. Thickening of the gastric remnant and obstructive jaundice were diagnosed in three cases. Since sonography is often used as the first imaging method in patients with abdominal complaints, knowledge about postsurgical appearance of the gastrointestinal tract is very important in detecting such pathological conditions.
