gastroscope       
noun [ C ]  medical specialized uk/ˈɡæs.trə.skəʊp/ us/ˈɡæs.trə.skoʊp/
 胃镜
a long, thin medical device that is used to examine the inside of the stomach
  A special instrument called a gastroscope is put in the mouth and passed down into the stomach.  一个叫做胃镜的特殊工具从口腔置入,下行到胃部。 
 The gastroscope is fitted with a tiny camera that allows the doctor to see the stomach lining.  胃镜上装有一个微小的摄像机,让医生可以看到胃的内壁。 
 - More examples
- The gastroscope was withdrawn into the esophagus.
- A gastroscope is inserted into the stomach and air insufflated.
- Abnormal tissue seen in a gastroscope examination will be biopsied by the surgeon.