Colon cancer is the second leading cause of cancer death in the United States. 1 Jemal A. Siegel R. Ward E. et al. Cancer statistics, 2008. CA Cancer J Clin. 2008; 58: 71-96 Crossref PubMed Scopus (10171) Google Scholar Colonoscopy is used to screen for colon cancer and adenomatous polyps. 2 U.S. Preventive Services Task ForceScreening for colorectal cancer: recommendation and rationale. Ann Intern Med. 2002; 137: 129-131 Crossref PubMed Scopus (550) Google Scholar , 3 Levin B. Lieberman D.A. McFarland B. et al. Screening and surveillance for the early detection of colorectal cancer and adenomatous polyps, 2008: a joint guideline from the American Cancer Society, the US Multi-Society Task Force on Colorectal Cancer, and the American College of Radiology. CA Cancer J Clin. 2008; 58: 130-160 Crossref PubMed Scopus (1378) Google Scholar Polyp detection rates depend on the proportion of mucosal surface inspected and have been correlated with the time dedicated to inspection during colonoscope withdrawal. 4 Barclay R.L. Vicari J.J. Doughty A.S. et al. Colonoscopic withdrawal times and adenoma detection during screening colonoscopy. N Engl J Med. 2006; 355: 2533-2541 Crossref PubMed Scopus (1074) Google Scholar A significant number of polyps are missed during colonoscopy, and in a review of studies using back-to-back colonoscopy design, the pooled miss rate for all polyps was reported to be 22% (95% CI, 19%-26%). 5 van Rijn J.C. Reitsma J.B. Stoker J. et al. Polyp miss rate determined by tandem colonoscopy: a systematic review. Am J Gastroenterol. 2006; 101: 343-350 Crossref PubMed Scopus (1022) Google Scholar The adenoma miss rate was 2% for lesions 10 mm or larger (95% CI, 0.3%-7.3%), 13% for lesions 5 to 10 mm (95% CI, 8%-18%) and 26% for lesions 1 to 5 mm (95% CI, 27%-35%).