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Retrograde Approach

The PowerSpiral Enteroscope may be used for retrograde examination of the small bowel, which is more complex than the antegrade approach. It requires additional maneuvers, especially during the colonoscopy phase of the procedure, enlisting loop reduction, manual abdominal compression, and passage through the ileocecal valve.

Entering the Colon

1. Forward rotation of the spiral segment is necessary for passage across the anal sphincter.

2. The colonoscopy is performed using standard technique supplemented by forward rotation of the spiral segment within the sigmoid.

3. Loops are reduced by withdrawing the enteroscope while simultaneously maintaining forward rotation of the spiral segment.

4. As the enteroscope enters the descending colon, minimal insufflation is continued. Forward push pressure is used with forward rotation of the spiral segment.

Stalling during sigmoid passage may indicate increased resistance. After a loop reduction effort, resume slow spiral forward motion. Use water irrigation for both lubrication and distention of the lumen.


Looping may also occur within the transverse colon. The same technique, withdrawing the enteroscope with forward rotation of the spiral segment, as used in the sigmoid, is also used in this location. The principal is to minimize the amount of scope inserted in the colon thereby preserving as much scope length as possible with which to examine the small bowel.

Passing through the ileocecal valve

1. Once the ileocecal valve is seen, it is approached for intubation with the tip of the enteroscope in the same fashion as during a colonoscopy.

2. Aided by manual abdominal compression as needed, forward rotation is used to allow the spiral segment to be advanced across the valve into the terminal ileum.

Passing through the Small Bowel

1. After the ileo-cecal valve and terminal ileum have been completely intubated, the enteroscope is advanced by maintaining forward rotation of the spiral segment with minimal manual movement of the enteroscope.

2. Bowel insufflation is minimized with the use of water irrigation to permit visualization during passage.

When the passage is stalling, there should be attention paid to the force gauge, especially if the limit stop function is activated and rotation of the spiral segment stops automatically. This indicates significant resistance against the bowel wall and further rotational advancement could lead to an adverse event.


With rotation of the spiral segment stopped, use water irrigation to lubricate the small bowel. Manual abdominal compression is then applied and passage with forward rotation of the spiral segment is resumed after first reducing any loops.

Withdrawal after maximal retrograde insertion


Maximal retrograde insertion can be recognized when further advancement stops despite the maneuvers described previously, if a tattoo placed during a prior integrate enteroscopy is seen, or the duodenum is identified. 

1. Withdrawal after maximal retrograde insertion is accomplished by using the backward foot switch pedal.

2. The speed of withdrawal can be altered by slowing backward rotation of the spiral segment while continuing to withdraw the enteroscope out of the patient.

3. If a lesion is encountered, the same maneuvers are used as described in the antegrade section.

4. Once the enteroscope has exited the ileocecal valve, it is removed from the colon in a standard fashion with the spiral segment maintained in backward mode, particularly when passing the anal sphincter.