The aim of this study is to evaluate the examination of the proximal colon with the retroflexion colonoscopic technique in terms of feasibility and its possible additive contribution in the detection of important lesions, namely polyps and cancers.

The investigators prospectively examined the additional diagnostic yield of right colon examination with colonoscope retroflexion in consecutive, symptomatic and screening - surveillance patients. Right colon was examined in forward-view first and thereafter, retroflexion was performed to re-inspect it.

Inclusion Criteria:

• patients undergoing elective colonoscopy in a Attikon University General Hospital.

Exclusion Criteria:

• patients aged <18 and >80 years;
• right colectomy;
• recent abdominalsurgery;
• multiple diverticula of the right colon;
• American Society of Anesthesiology (ASA) physical status classification grade IV;
• inflammatory bowel disease and polyposis syndromes.