Effect of Water Exchange Plus Acetic Acid Staining on the Detection of Flat Polyps During Colonoscopy

Study Overview
=================
Brief Summary
-----------------
Our previous study (Am. J. Gastroenterol. 2017 04;112(4)) showed that water exchange (WE) colonoscopy was able to increase the detection of flat adenomas as well as overall ADR. We hypothesized that WE based whole-colon acetic acid（AA） staining might be useful to improve the detection of flat lesions compared with WE alone.

Detailed Description
-----------------
Water exchange colonoscopy was performed as described previously (Am. J. Gastroenterol. 2017 04;112(4)). Patients were randomly allocated to WE group or WE+AA group. In WE+AA group, water containing 1% of AA was used during insertion of colonoscopy instead of water alone. A bottle of 20ml pure AA was placed abutting the water pump, which make it possible to keep patients blinded to group allocation. Endoscopist using a high-definition wide-angle Olympus or Fujinum colonoscope performed all of the colonoscopies, with a withdrawal time of at least 6 min. The observation was initially performed without the assistance of cap or the use of magnification or electronic staining (NBI, BLI, LCI or AFI et al.). Scopolamine butylbromide or glucogon was not routinely administrated.

Official Title
-----------------
Effect of Water Exchange Plus Acetic Acid Staining on the Detection of Flat Polyps During Screening and Surveillance Colonoscopy: a Multi-centered, Randomized Controlled Study.

Conditions
-----------------
Adenoma Colon

Intervention / Treatment
-----------------
* Other: acetic acid staining
* Other: Water exchange colonoscopy


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Aged 40-70 Undergoing colonoscopy after standard bowel preparation Exclusion Criteria: Known familial polyposis Small amount of feces or semi-solid stool in last rectal effluent Inflammatory Bowel Disease Lactated or pregnant women Unable to provide informed content

Ages Eligible for Study
-----------------
Minimum Age: 40 Years
Maximum Age: 70 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: WE+AA group<br>Water containing 1% of AA was used during insertion of colonoscopy using water exchange method. | Other: acetic acid staining<br>* The water exchange colonoscopy is used during insertion procedure, in which the water contains 1% acetic acid, and the liquid is absorbed during the withdrawal process for observation.<br>|
| Active Comparator: WE group<br>Water exchange colonoscopy was used for standard screening or surveillance colonoscopy. | Other: Water exchange colonoscopy<br>* The water exchange colonoscopy is used during insertion procedure, and the liquid is absorbed during the withdrawal process for observation.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of flat polyps per patient | average numbers of flat polyps, defined by Paris classification IIa/IIb/IIc, for each patient | 9 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall ADR | Adenoma detection rate, defined as the proportion of subjects with at least one adenoma of any size, in each group. | 9 months | 
| Advanced ADR | Advanced adenoma detection rate. Advanced adenoma: any with 3 or more adenomas of any size, 1 or more large adenomas 1 cm, or 1 or more adenomas with villous architecture or highgrade dysplasia. | 9 months | 
| SSA/P detection rate | SSA/P detection rate, defined as the proportion of subjects with at least one sessile serrated adenoma/polyp (SSA/P) of any size, in each group. | 9 months | 
| Flat neoplasms located in proximal colon | Low-grade adenoma, adenoma with villous components, high-grade adenoma, noninvasive carcinoma, and invasive carcinoma in proximal colon | 9 months | 
| Adverse events | the rate of bleeding and perforation during colonoscopy procedure and abdominal pain, diarrhea, hematochezia and change of defecation habit Within one week. | 9 months | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Water exchange colonoscopy, Flat Polyps, Acetic Acid Staining