Upper Gastrointestinal Endoscopy and Mucosal Biopsy

Upper gastrointestinal endoscopy, often referred to as EGD (esophago-gastro-duodenoscopy), is a common investigation that allows the physician to directly examine the esophagus, stomach, and duodenum. EGD also allows mucosal biopsies to be obtained as well as various therapeutic interventions to be performed. The endoscopy system had evolved from the fiberoptic technology in the 1960s to the state-of-art high-resolution and high-definition systems of today. Currently, endoscopes with integrated zoom lenses and microscopes are available and with these technologies, intestinal tissues can be imaged at cellular and nuclear levels which provide invivo optical histology. Image enhancement by altering the spectrum of visible light has allowed the delineation and characterization of subtle and early abnormalities of the gastrointestinal tract. This chapter will provide an overview of the endoscopic techniques and recent developments in this field.