In May 2016, a 70-year-old male underwent total gastrectomy with R-Y reconstruction using a stapled anastomosis for gastric cancer. Although no recurrence occurred postoperatively, the patient visited the outpatient department in March 2017 with the chief complaint of abdominal distension. An abdominal CT revealed a significant dilation of the afferent loop, leading to the diagnosis of afferent loop syndrome due to R-Y anastomotic site occlusion. Upon hospitalization, we performed single-balloon small-bowel endoscopy and identified the estimated site of an anastomosis using the Y-loop anastomotic site stapler position as a marker under fluoroscopy. Endoscopic findings suggested a white-colored region surrounded by the stapler with no intestinal mucosa, leading to our diagnosis of scar tissue due to anastomotic stricture. An endoscopic retrograde cholangiopancreatography catheter used to investigate the site could pass through the Y loop, and balloon dilation was performed.
