Examining Techniques on Adenoma Miss Rate in Proximal Colon

Study Overview
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Brief Summary
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The primary aim of this study is - to explore the usefulness of re-examination and retroflexion on adenoma miss rate (AMR) in the proximal colon. Other aims include to explore the data below when re-examination or retroflexion is used. Adenoma detection rate, ADR Polyp miss rate, PMR Polyp detection rate, PDR Withdrawal time, WT

Detailed Description
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AMR = number of adenomas missing during the first examination/ total number of adenomas in both examinations = number of adenomas detected only in the second examination/(number of adenomas detected during the first examination + number of adenomas detected only in the second examination)

Official Title
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Efficacy of Segmental Re-examination and Retroflexion of Proximal Colon for Adenoma Miss Rate During Colonoscopy

Conditions
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Colorectal Adenoma, Colorectal Polyp

Intervention / Treatment
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* Procedure: Retroflexion
* Procedure: Re-examination


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients between 45 and 80 years who undergo colonoscopy examination for screening, and who receive primary screening and get positive result Exclusion Criteria: Pregnant female patients Patients received colonoscopy in the past 5 years Patients who have history of colorectal cancer, colorectal polyposis, inflammatory bowel disease or heredity colorectal neoplasm syndrome such as familiar adenomatous polyposis, Lynch Syndrome and so on Patients who had previous abdominal surgery Patients who are known to have colonic stricture or obstructing tumor from the results of radiography (X ray, CT scan or barium enema) Patients who are presenting acute surgical conditions such as severe colitis, megacolon and active gastrointestinal bleeding Patients who have inadequate bowel preparation Patients who reject to participate in this study

Ages Eligible for Study
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Minimum Age: 45 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Re-examination Group<br>Routine intubation is performed. After cecal intubation, the cecum and ascending colon is examined with colonoscope tip in forward direction for the first time. Re-intubation is performed after the first examination of the cecum and ascending colon, and then this region of the large bowel is re-examined in the same fashion. After that, the rest of the colon is examined in routine method. | Procedure: Re-examination<br>* Re-examination in colonoscopy means examining the cecum and ascending colon twice in the routine fashion.<br>|
| Experimental: Retroflexion Group<br>Routine intubation is performed. After cecal intubation, the cecum and ascending colon is examined with colonoscope tip in forward direction for the first time. Re-intubation is performed after the first examination of the cecum and ascending colon, and then this region of the large bowel is re-examined with the colonoscope tip in reverse direction (retroflexion fashion). After that, the rest of the colon is examined in routine method. | Procedure: Retroflexion<br>* Retroflexion technique in colonoscopy means turning the colonoscope tip 180 degree in order to look backward in the colon and rectum.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Adenoma miss rate in the proximal colon (AMR) | AMR refers to the rate of adenoma missing, calculated as the proportion of adenomas which are missing in the first examination. AMR in the proximal colon is calculated with only the proximal colon concerned. | At the end of the procedure, up to 1 hour | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Adenoma Detection Rate in the proximal colon (ADR) | ADR refers to the rate of adenoma detection, calculated as the proportion of subjects with at least one adenoma. ADR in the proximal colon is calculated with only the proximal colon concerned. | At the end of the procedure, up to 1 hour | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Colonoscopy, Lower Gastrointestinal Tract, Re-examination, Retroflexion