Diagnosis of angiodysplasia is often accomplished with endoscopy, either colonoscopy or esophagogastroduodenoscopy (EGD). Whole bowel irrigation with macrogol is part of the bowel preparation before surgery or colonoscopy. Diagnosis is typically by colonoscopy with tissue biopsies. During a colonoscopy, biopsies of the colon are often taken to confirm the diagnosis. The diagnosis is usually confirmed by biopsies on colonoscopy. During colonoscopy, small polyps may be removed if found. These robotics can remove a polyp during a colonoscopy. Dexmedetomidine can also be used for procedural sedation such as during colonoscopy. Other options include virtual colonoscopy and stool DNA screening testing (FIT-DNA). A striking finding was in a study of colonoscopy patients. One of the most serious complications that may arise after colonoscopy is the postpolypectomy syndrome. Surgeons have used the term pouchoscopy to refer to a colonoscopy of the ileo-anal pouch. Dotti died in Rome on 30 September 2007 after complications from a colonoscopy. It is also used to empty the bowels before a colonoscopy. The CONFIRM trial, a randomized trial on colonoscopy vs. FIT is currently ongoing.