NAVLE（北美执业兽医考题）Day 515

A nine-year-old Irish setter is presented for vomiting. The owner states that the dog does not really retch, but just spits up food soon after eating. The dog is normal otherwise. Based on the lateral radiograph below, which one of the following choices is the most likely diagnosis? 

一只9岁的爱尔兰塞特犬表现呕吐。 畜主说狗并不是真正的呕吐，只是在吃完东西不久后立即吐出食物。 狗的其他方面是正常的。 根据下面的侧位片，下列哪一项是最可能的诊断？