Flexible sigmoidoscopy is a limited form of a colonoscopy performed to evaluate the last part of the colon (large intestine). The scope is the same as used in a full colonoscopy however it is not inserted as far during this limited exam. The colonoscope is a thin flexible tube that has a light source, a video source and multiple channels that allow your doctor to simultaneously watch live video of the last part your large intestine and take biopsies or remove polyps if necessary. In order for the exam to be performed patients typically receive intravenous sedation. Occasionally patients may have the exam performed without sedation which is not painful for this limited exam. You can discuss the specific options with your doctor in the office.