Clinical trial · Interventional
Water-aided Colonoscopy vs Air Insufflation Colonoscopy in Colorectal Cancer Screening
A Randomized, Controlled Trial Comparing Air Insufflation, Water Immersion and Water Exchange for Adenoma Detection Rate in Screening Colonoscopy
- Source
- ClinicalTrials.gov
- Retrieved
- Sep 8, 2026
- Layer
- normalized (units and labels harmonized; values unchanged)
- Run
- ING-CLINICALTRIALS-20260908-000001
Summary
Brief summary (as posted)
The degree of protection afforded by colonoscopy against proximal colorectal cancer (CRC) appears to be related to the quality of the procedure, and the incomplete removal of lesions has been shown to increase the subsequent risk of developing a colon cancer. Some studies suggest that small polyps with advanced histology are more common in the right than in the left colon (right colon proximal to splenic flexure, left colon distal to the splenic flexure). The average size of polyps in the right colon with advanced pathology or containing adenocarcinoma was ≤9 mm, whereas in the left colon their average size was \>9 mm, P\<0.001. Inadequate prevention of right-sided CRC incidence and mortality may be due to right-sided polyps with advanced histology or that harbor malignancy. These presumptive precursors of cancer are smaller and possibly more easily obscured by residual feces, and more likely to be missed at colonoscopy. Water-aided colonoscopy (WAC) can be subdivided broadly into two major categories: water immersion (WI), characterized by suction removal of the infused water predominantly during the withdrawal phase of colonoscopy, and water exchange (WE), characterized by suction removal of infused water predominantly during the insertion phase of colonoscopy. In some reports WE appeared to be superior to both WI and air insufflation colonoscopy (AI) in terms of pain reduction and adenoma detection, particularly for \<10 mm adenomas in the proximal colon. In this multicenter, double-blinded randomized controlled trial (RCT) we test the hypothesis that that WE, compared to AI and WI, will enhance overall Adenoma Detection Rate (ADR) in CRC screening patients. Confirmation of the primary hypothesis will provide evidence that WE enhances the quality of screening colonoscopy. We also hypothesize that WE may be more effective in detecting proximal colon adenomas than WI and AI, particularly \<10 mm adenomas, thus increasing proximal colon ADR and proximal colon ADR \<10 mm. Confirmation of secondary hypotheses will provide justification for further testing that WE may provide a strategy to improve prevention of colorectal cancer by increasing detection of adenomas in screening colonoscopy. Unlike previous reports of single colonoscopist studies, the insertion and withdrawal phases of colonoscopy will be done by different investigators. The second investigator will be blinded to the method used to insert the instrument, thus eliminating possible bias about procedure related issues. Several secondary outcomes will also be analysed.
Conditions
Conditions (4)
Free-text conditions as registered, with the CancerIndex entity they were reconciled to and the match type.
| Condition (as posted) | Mapped entity | Match | Confidence |
|---|---|---|---|
| Colorectal Adenomas | — | UNRESOLVED | — |
| Colorectal Cancer | Malignant Colorectal Neoplasm | CURATED_BROADER | 0.80 |
| Colorectal Polyps | — | UNRESOLVED | — |
| Pain | — | UNRESOLVED | — |
Interventions
Interventions (3)
| Intervention | Type | Mapped drug | Match |
|---|---|---|---|
| Air insufflation method. | Other | — | UNRESOLVED |
| Water Exchange method. | Other | — | UNRESOLVED |
| Water Immersion method. | Other | — | UNRESOLVED |
Design
Arms and outcomes
Arms (3)
- type
- ACTIVE_COMPARATOR
- label
- Air insufflation method.
- description
- Colonoscopy performed in the standard fashion, with the minimal air insufflation required to aid insertion and allowing for washing as needed. Considered to be standard procedure.
- interventionNames
- Other: Air insufflation method.
- type
- EXPERIMENTAL
- label
- Water Immersion method.
- description
- Infusion of water during the insertion phase of colonoscopy mainly to open the colonic lumen and progress to the cecum immersed in the water environment thus created, without attempting to clear the colon contents. Residual air in the colon will not be removed. Infused water and residual feces will be suctioned back predominantly during withdrawal. Insufflation not used until the cecum is reached. It will be allowed only 3 times and no more than 10 seconds each time (ITT failure if \>3) if the lumen cannot be seen. Withdrawal phase done using air insufflation.
- interventionNames
- Other: Water Immersion method.
Eligibility
Eligibility (as posted)
- Sex
- All
- Minimum age
- 50 Years
- Maximum age
- 70 Years
Show eligibility criteria text
Inclusion Criteria: * consecutive screening patients Exclusion Criteria: * previous colonoscopy within 5 years * surveillance colonoscopy * previous colorectal surgery * indication for a proctosigmoidoscopy or bidirectional endoscopy * history of inflammatory bowel disease * patient refusal or inability to provide informed consent * inadequate consumption of bowel preparation
References
Publications (7)
- BACKGROUNDLeung FW, Amato A, Ell C, Friedland S, Harker JO, Hsieh YH, Leung JW, Mann SK, Paggi S, Pohl J, Radaelli F, Ramirez FC, Siao-Salera R, Terruzzi V. Water-aided colonoscopy: a systematic review. Gastrointest Endosc. 2012 Sep;76(3):657-66. doi: 10.1016/j.gie.2012.04.467. PMID 22898423
- BACKGROUNDGupta S, Balasubramanian BA, Fu T, Genta RM, Rockey DC, Lash R. Polyps with advanced neoplasia are smaller in the right than in the left colon: implications for colorectal cancer screening. Clin Gastroenterol Hepatol. 2012 Dec;10(12):1395-1401.e2. doi: 10.1016/j.cgh.2012.07.004. Epub 2012 Jul 24. PMID 22835574
- BACKGROUNDCadoni S, Gallittu P, Sanna S, Fanari V, Porcedda ML, Erriu M, Leung FW. A two-center randomized controlled trial of water-aided colonoscopy versus air insufflation colonoscopy. Endoscopy. 2014 Mar;46(3):212-8. doi: 10.1055/s-0033-1353604. Epub 2013 Nov 11. PMID 24218307
- BACKGROUNDRadaelli F, Paggi S, Amato A, Terruzzi V. Warm water infusion versus air insufflation for unsedated colonoscopy: a randomized, controlled trial. Gastrointest Endosc. 2010 Oct;72(4):701-9. doi: 10.1016/j.gie.2010.06.025. PMID 20883846
- BACKGROUNDLeung FW. Water-aided colonoscopy. Gastroenterol Clin North Am. 2013 Sep;42(3):507-19. doi: 10.1016/j.gtc.2013.05.006. PMID 23931857
- BACKGROUNDRabenstein T, Radaelli F, Zolk O. Warm water infusion colonoscopy: a review and meta-analysis. Endoscopy. 2012 Oct;44(10):940-51. doi: 10.1055/s-0032-1310157. Epub 2012 Sep 17. PMID 22987214
- DERIVEDCadoni S, Falt P, Rondonotti E, Radaelli F, Fojtik P, Gallittu P, Liggi M, Amato A, Paggi S, Smajstrla V, Urban O, Erriu M, Koo M, Leung FW. Water exchange for screening colonoscopy increases adenoma detection rate: a multicenter, double-blinded, randomized controlled trial. Endoscopy. 2017 May;49(5):456-467. doi: 10.1055/s-0043-101229. Epub 2017 Mar 10.