Which type of scope is used to view the esophagus?

The gastroscope is specifically designed for examining the upper gastrointestinal tract, which includes the esophagus, stomach, and the beginning of the small intestine (the duodenum). This type of endoscope is equipped with a light source and a camera, allowing for visual inspection and treatment procedures in these areas.

The gastroscope enables healthcare providers to diagnose conditions such as gastroesophageal reflux disease (GERD), esophageal strictures, and various other esophageal disorders. It can also facilitate interventions such as biopsies, dilations, or the removal of foreign bodies.

In contrast, the other options serve different purposes: the colonoscope is intended for examining the large intestine, the sigmoid scope is specifically for the sigmoid colon, and the duodenoscope is used to examine and treat issues in the duodenum. None of these scopes are suitable for directly viewing the esophagus, making the gastroscope the appropriate choice for that purpose.