What device is used to inspect the internal linings of the stomach and duodenum?

The device used to inspect the internal linings of the stomach and duodenum is an endoscope. This instrument is specifically designed for direct visualization within the gastrointestinal tract. An endoscope is a flexible tube equipped with a camera and light source, allowing healthcare providers to effectively examine the mucosal surfaces of these organs.

The endoscopic procedure not only facilitates visualization but also allows for potential therapeutic interventions such as biopsies or the removal of polyps. This level of direct inspection is crucial when diagnosing conditions such as ulcers, tumors, or inflammation within the stomach and duodenum.

Other imaging modalities listed, such as CT scanners or ultrasound, provide valuable information about the structures surrounding the gastrointestinal tract but do not allow for direct visualization of the internal lining. X-ray fluoroscopy can visualize the passage of barium through the gastrointestinal tract and identify abnormalities, but it does not provide the same detailed view of the mucosal surface as direct endoscopy does. Thus, while some of the other options may be useful for related assessments, none can replace the direct visual diagnostic capabilities of the endoscope when it comes to inspecting the stomach and duodenum.