Endoscopy refers to any study performed with a lighted, long and flexible fiber-optic camera. It is commonly used to describe studies of the gastrointestinal tract such as a colonoscopy, sigmoidoscopy, and upper endoscopy or esophago-gastro-duodenoscopy (EGD). Endoscopy can also be used to describe evaluation of the bladder (cystoscopy), the lungs (bronchoscopy), and the uterus (hysteroscopy) to name a few. Colon and Rectal Surgeons routinely perform colonoscopies and flexible sigmoidoscopies.