Retroflexion in the Entire Colon for the Detection of Colon-related Diseases

Colorectal cancer is one of the common gastrointestinal malignancies, and the incidence of colorectal cancer in China increases by 3% to 4% annually . Colorectal adenoma is the most important precancerous lesion of colorectal cancer. Timely screening for colorectal adenoma and endoscopic resection is the most effective measure to prevent colorectal cancer .Removal of pre-malignant colon polyps during colonoscopy reduces colorectal cancer mortality by over 50%. However,Conventional colonoscopy endoscopy is a direct-view type, and the visual field is limited. About 10%-24% of the lesions may be missed. The ascending colon is more difficult because of the deep folds, and the rate of missed diagnosis is higher. Our goal is to determine if additional pre-cancerous colon polyps can be identified by looking at the total colon in retroflexion. During retroflexion the tip of the colonoscope is turned 180 degrees; allowing the doctor to view the backs of colonic folds. If additional polyps can be identified in this manner colonoscopy will become a more efficient method of screening for colon cancer. In order to evaluate how effective colon retroflexion is at detecting polyps in the total colon the investigators plan on performing a randomized, controlled trial. Patients undergoing screening or follow up colonoscopy will be invited to participate in the study. Those patients who agree to participate will be randomized into one of two groups once the colonoscope is fully inserted. Group one will have their colon examined for polyps with the endoscope looking forward (traditional form of examination) followed by repeat examination of the total colon with the colonoscope in retroflexion (looking backwards). In group two the colonoscopy will be completed in the usual manner. Polyps seen during each section of the exam will be recorded. The duration of each portion of colonoscopy will be recorded. After the procedure is completed the physician performing the colonoscopy will rate difficulty of the procedure and confidence with quality of the examination. Assess and record the degree of pain during and after the patient's examination.Pathology results for each polyp will be recorded once available. There will be no study related follow up after the pathology results are recorded.

Sex

All

Minimum age

18 Years

Inclusion Criteria:

* Patients \>18 years of age undergoing colonoscopy for colorectal cancer screening or routine polyp surveillance

Exclusion Criteria:

* Failure to intubate the cecum during colonoscope insertion
* Prior right colon resection
* Known polyposis syndrome or polyposis identified at colonoscopy
* Inflammatory bowel disease
* Preparation of the colon is judged fair or poor using Boston Bowel Preparation Scale.
* Severe cardio-cerebral diseases
* Pregnant women, lactating women
* Acute lower gastrointestinal bleeding
* Preoperative use of antispasmodic sedative drugs

• RESULTCohen J, Grunwald D, Grossberg LB, Sawhney MS. The Effect of Right Colon Retroflexion on Adenoma Detection: A Systematic Review and Meta-analysis. J Clin Gastroenterol. 2017 Oct;51(9):818-824. doi: 10.1097/MCG.0000000000000695. PMID 27683963
• RESULTKushnir VM, Oh YS, Hollander T, Chen CH, Sayuk GS, Davidson N, Mullady D, Murad FM, Sharabash NM, Ruettgers E, Dassopoulos T, Easler JJ, Gyawali CP, Edmundowicz SA, Early DS. Impact of retroflexion vs. second forward view examination of the right colon on adenoma detection: a comparison study. Am J Gastroenterol. 2015 Mar;110(3):415-22. doi: 10.1038/ajg.2015.21. Epub 2015 Mar 3. PMID 25732415