Upper gastrointestinal series were done in 4 patients, with dilatation of the duodenum and a corkscrew appearance in 3 (Figure 2) and only dilatation of the duodenum with a sudden cutoff in 1.

• 4例病人做了上消化道摄影术，3例发现十二指肠扩张，呈拔钻形（图2），1例十二指肠扩张并突然截断。