This is a test in which a thin, black, flexible tube with a lighting system on the end is passed through the anus, into the rectum, in order to examine the large bowel or intestine, also called the colon. Colonoscopy is a very good test for examining the colon for polyps (warty growths that can turn into cancer), but it is not perfect. In fact, about 30% of polyps that are under 5 mm (about 1/5 of an inch) in size are missed during colonoscopy because they are hiding behind folds and bends in the colon. This research study is being done to determine if performing colonoscopy with a cap on the tip of the colonoscope will reduce the miss rate for polyps. A cap is a clear plastic hood that fits on the tip of the colonoscope and sticks out about 1/3 of an inch. During colonoscopy, the cap can be pressed against a fold or ridge in order to flatten it, so that the lining on the other side can be more easily seen. This may reduce the miss rate for colon polyps.
Primary Outcome Measures:
- The number of polyps found during the first colonoscopy will be compared to the number of polyps found during the second colonoscopy to determine the miss rate. [ Time Frame: after the second colonoscopy is completed ] [ Designated as safety issue: No ]
Secondary Outcome Measures:
- The time required to remove and retrieve polyps with and without the cap on will be measured using a stopwatch as a secondary end point. [ Time Frame: after both colonoscopies are completed ] [ Designated as safety issue: No ]
Estimated Enrollment: |
250 |
Study Start Date: |
November 2006 |
Estimated Study Completion Date: |
November 2011 |
Estimated Primary Completion Date: |
November 2011 (Final data collection date for primary outcome measure) |
1: Experimental
cap that fits on the end of a colonoscope
|
Device: colonoscope cap
Subjects will be randomized to either cap-fitted colonoscope or regular colonoscope for their scheduled colonoscopies.
|
2: Active Comparator
no cap on the end of the colonoscope
|
Device: regular colonoscope
Subjects will be randomized to either regular colonoscope or capfitted colonoscope for their scheduled colonoscopies
|
Patient will undergo tandem colonoscopy on the same day using propofol sedation. Patients will undergo one colonoscopy without the cap and a second colonoscopy with the cap on. We will endeavor to keep the total examination time equal between the groups and approximately six minutes. The order in which patients receive the two colonoscopies (i.e. cap or without cap first) will be randomized. Any polyps detected during the first colonoscopy will be removed during that procedure. During the withdrawal phase, the time for examination will be measured with a stopwatch, and the stopwatch will be stopped at any time a polyp is located and restarted when the polyp has been removed and retrieved. The stopwatch will also be stopped for suctioning fluid or washing debris from the colon surface. Any polyp detected and removed during the first colonoscopy will be counted as the detection for that procedure. During the second colonoscopy, all polyps will also be removed when detected. Any polyp identified and removed during the second procedure will be counted as a miss for the first procedure. All polyps will be sent separately for pathologic evaluation. The time required to remove and retrieve polyps with and without the cap on will be measured using a stopwatch as a secondary end point. The primary end point will be the miss rate for colonoscopy with the cap and colonoscopy without the cap.