Fig. 4.72 The endoscope is a flexible plastic tube that can be controlled from the proximal end. Through a side portal various devices can be inserted, which run through the endoscope and can be used to obtain biopsies and to perform minor endoluminal surgical procedures (e.g., excision of polyps).
Fig. 4.73 Endoscopic images of the gastroesophageal junction. A. Normal. B. Esophageal cancer at esophageal junction.