Several novel imaging technologies are currently used for detection and differentiation of colonic polyps during colonoscopy, such as NBI (Olympus), FICE (Fujinon), and i-Scan (Pentax).

Several previous studies have indicated that NBI without magnification can be useful for real-time differentiation of diminutive colonic neoplasias.

To date, however, there are no studies comparing NBI with other imaging systems (FICE or i-Scan) for differentiation of diminutive colonic polyps.

The study objectives are to compare the diagnostic efficacy of NBI with that of i-Scan in real-time prediction of diminutive colonic polyps.

In this prospective pilot study, diminutive colonic polyps detected during colonoscopy will be observed with conventional colonoscopy, thereafter will be observed with new imaging systems.

Sensitivity, specificity, and diagnostic accuracy of both NBI and i-Scan will be assessed by reference to histological results obtained by endoscopic biopsy or polypectomy.

Inclusion Criteria:

• screening or surveillance colonoscopy
• age over 18
• informed consent

Exclusion Criteria:

• history of inflammatory bowel diseases
• history of hereditary colorectal cancers and polyposis syndrome
• inability to give informed consent
• use of antiplatelet agent and anticoagulants
• pregnancy