Colonoscopy is the gold standard investigation for the diagnosis of bowel pathology and colorectal cancer screening. Adenoma detection rate is a marker of high quality colonoscopy. In this study we compare two devices: Endocuff (TM) and cap that can increase the adenoma detection rate during colonoscopy.

Colonoscopy is the gold standard investigation for the diagnosis of bowel pathology and colorectal cancer screening. Adenoma detection rate is a marker of high quality colonoscopy and a high adenoma detection rate is associated with a lower incidence of interval cancers. Several technological advancements have been explored to improve adenoma detection rate. Endocuff Vision™ has been shown to improve adenoma detection rate in several studies. Cap-assisted colonoscopy is a technique that allow improved visualization of the colonic folds by flattening the fold within the viewing field. However, studies have reported mixed results on adenoma detection in cap-assisted colonoscopy.

This is a prospective, single-centre, randomized controlled trial comparing the adenoma detection rate in patients undergoing Endocuff Vision™-assisted colonoscopy versus cap-assisted colonoscopy. Patients are randomized according to bowel cancer screening status to receive Endocuff Vision™-assisted colonoscopy or cap colonoscopy on the day of procedure. Baseline data, colonoscopy, and polyp data including histology are collected. Patients are followed up at 30 days for complications. This study will take place in an University Hospital in Spain. A maximum of 9 expert colonoscopists will recruit a total of 712 patients.

This is the first trial to evaluate the adenoma detection rate of Endocuff Vision™ vs cap colonoscopy in all screening, surveillance, and diagnostic patient groups. This study will guide clinicians to decide what device to use to increase adenoma detection rate in routine colonoscopy

Inclusion Criteria:

• All patients who are attending for screening, surveillance or diagnostic colonoscopy.

Exclusion Criteria:

• patients with absolute contraindications to colonoscopy;
• patients with established or suspicion of large bowel obstruction or pseudo-obstruction;
• patients with known colonic strictures;
• patients with a known severe diverticular segment (that is likely to impede colonoscope passage);
• patients with active or known colitis (ulcerative colitis, Crohn's colitis, diverticulitis, infective colitis);
• patients lacking capacity to give informed consent;
• patients on clopidogrel, warfarin, or other new generation anticoagulants who have not stopped this for the procedure;
• patients who are attending for a therapeutic procedure or assessment of a known lesion, or submitted for rectoscopy or rectosigmoidoscopy;
• examination performed by a non-expert colonoscopist;
• pregnancy.