Original article
Experimental endoscopy
Active locomotion of a paddling-based capsule endoscope in an in vitro and in vivo experiment (with videos)

https://doi.org/10.1016/j.gie.2009.12.058Get rights and content

Background

Capsule endoscopy that could actively move and approach a specific site might be more valuable for the diagnosis or treatment of GI diseases.

Objective

We tested the performance of active locomotion of a novel wired capsule endoscope with a paddling-based locomotion mechanism, using 3 models: a silicone tube, an extracted porcine colon, and a living pig.

Design

In vitro, ex vivo, and in vivo experiments in a pig model.

Setting

Study in an animal laboratory.

Interventions

For the in vitro test, the locomotive capsule was controlled to actively move from one side of a silicone tube to the other by a controller-operated automatic traveling program. The velocity was calculated by following a video recording. We performed ex vivo tests by using an extracted porcine colon in the same manner we performed the in vitro test. In in vivo experiments, the capsule was inserted into the rectum of a living pig under anesthesia, and was controlled to move automatically forward. After 8 consecutive trials, the velocity was calculated.

Main Outcome Measurements

Elapsed time, velocity, and mucosal damage.

Results

The locomotive capsule showed stable and active movement inside the lumen both in vitro and ex vivo. The velocity was 60 cm/min in the silicone tube, and 36.8 and 37.5 cm/min in the extracted porcine colon. In the in vivo experiments, the capsule stably moved forward inside the colon of a living pig without any serious complications. The mean velocity was 17 cm/min over 40 cm length. We noted pinpoint erythematous mucosal injuries in the colon.

Limitation

Porcine model experiments, wired capsule endoscope.

Conclusions

The novel paddling-based locomotive capsule endoscope performed fast and stable movement in a living pig colon with consistent velocity. Further investigation is necessary for practical use in humans.

Section snippets

In vitro experiment

To investigate the high performance of locomotion, an in vitro test was done with a silicone tube that does not yield elastic deformation against paddles of the locomotive CE. This model enables the locomotive CE to move without losing friction. The silicone tube, which had a length of 50 cm, an inner diameter of 18 mm, and a maximum slope angle of 27.5°, was laid on a planar surface (Fig. 3). The locomotive CE was inserted into the end of the tube and allowed to move forward by a

In vitro experiment

In the silicon tube, the locomotive CE stably advanced from one end to the other. The elapsed time was 50 seconds for a 50-cm-long tube, and the calculated average velocity was 10 mm/s (60 cm/min).

Ex vivo experiment

The locomotive CE stably moved forward inside the extracted porcine colon without a stop (Video 1, available online at www.giejournal.org). When the slope angle was 27.5°, the elapsed time was 56 seconds for a 35-cm-long path. When the slope angle was 37.5°, the elapsed time was 101 seconds for a

Discussion

Many research groups have performed various trials to develop a CE that is capable of active locomotion and have found many issues that need to be addressed beforehand. The first purpose of CE with active locomotion is to examine the esophagus, stomach, small bowel, and large bowel. Standard endoscopy such as EGD, enteroscopy, and colonoscopy are excellent tools to examine the GI tract, but they need GI endoscopists' physical maneuvering and patients' patience. Recently, CEs for the esophagus,

Acknowledgments

The authors give special thanks to Young Soo Park, MD, and Chang Woo Gham, MD.

References (18)

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DISCLOSURE: All authors disclosed no financial relationships relevant to this publication. (Research support for this study was provided by the Intelligent Microsystem Center, which carries out one of the 21st Century Frontier R&D Projects sponsored by the Ministry of Knowledge Economy of Korea.)

If you want to chat with an author of this article, you may contact Dr Bang at [email protected].

The first two authors contributed equally to this work.

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