Try our beta test site
IMPORTANT: Listing of a study on this site does not reflect endorsement by the National Institutes of Health. Talk with a trusted healthcare professional before volunteering for a study. Read more...

Right-sided Retroflexion With Standard Adult Versus Pediatric Colonoscopes

This study has been withdrawn prior to enrollment.
(PI has left institution)
Information provided by (Responsible Party):
Medical College of Wisconsin Identifier:
First received: August 28, 2012
Last updated: January 6, 2016
Last verified: January 2016

Screening colonoscopy has been shown to be less effective in preventing colorectal cancer in the proximal colon compared to the distal colon. Possible reasons for this include bowel preparation often being worse in the proximal colon as well as flat depressed lesions being more common in the proximal colon.

Retroflexion is commonly regarded as standard practice in the rectum, but retroflexion in the proximal colon is not currently routinely performed due to concerns of perforation and possibly because of the increased time required.

Proximal colon retroflexion has been shown to be safe and effective without any complications, but data regarding ability to retroflex with certain types of colonoscopes is limited. Endoscopists interchangeably use standard adult colonoscopes or pediatric colonoscopes. Studies have not been performed to comparatively evaluate the success rates of standard adult and pediatric colonoscopes and whether either type of instrument confers a greater polyp detection rate.

Condition Intervention
Colonic Neoplasms
Procedure: Retroflexion with the adult colonoscope.
Procedure: Retroflexion with the pediatric colonoscope.

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Diagnostic
Official Title: Right-sided Retroflexion With Standard Adult Versus Pediatric Colonoscopes

Further study details as provided by Medical College of Wisconsin:

Primary Outcome Measures:
  • Percentage of cases in which right-sided retroflexion is successful with the adult and pediatric colonoscopes. [ Time Frame: After 50% and 100% of patient enrollment is complete. ]

Secondary Outcome Measures:
  • Adenoma detection rate in forward and retroflexed views. [ Time Frame: After 50% and 100% of patient enrollment is complete. ]
  • Reasons for failure of retroflexion. [ Time Frame: After 50% and 100% of patient enrollment is complete. ]
    This will be assessed as a yes/no variable. In addition, the specific reasons that the endoscopist could not retroflex the colonoscope in the right colon will assessed, such as the colonoscope not being able to be advanced to the cecum, small diameter of the right colon, too much resistance encountered when attempting retroflexion that the endoscopist does not feel comfortable with, etc.

Enrollment: 0
Study Start Date: February 2012
Study Completion Date: May 2013
Primary Completion Date: May 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Adult colonoscope
Use of the adult colonoscope.
Procedure: Retroflexion with the adult colonoscope.
Active Comparator: Pediatric colonoscope
Use of the pediatric colonoscope.
Procedure: Retroflexion with the pediatric colonoscope.


Ages Eligible for Study:   18 Years to 100 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Adult patients over the age 18 undergoing screening or surveillance colonoscopy

Exclusion Criteria:

  • Age less than 18
  • Pregnant
  • History of ulcerative colitis or Crohn's disease
  • History of polyposis syndromes
  • History of colon resection
  • Colonoscopy being performed for diagnostic purposes (ie. bleeding, abdominal pain, alternating bowel habits)
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01675934

United States, Wisconsin
Froedtert Surgery Center
Milwaukee, Wisconsin, United States, 53226
Sponsors and Collaborators
Medical College of Wisconsin
Principal Investigator: Young Oh, MD Medical College of Wisconsin
  More Information

Responsible Party: Medical College of Wisconsin Identifier: NCT01675934     History of Changes
Other Study ID Numbers: PRO00017208
Study First Received: August 28, 2012
Last Updated: January 6, 2016

Additional relevant MeSH terms:
Colonic Neoplasms
Colorectal Neoplasms
Intestinal Neoplasms
Gastrointestinal Neoplasms
Digestive System Neoplasms
Neoplasms by Site
Digestive System Diseases
Gastrointestinal Diseases
Colonic Diseases
Intestinal Diseases processed this record on May 25, 2017