Therapeutic Capsule Endoscopes
A new controllable device for minimally invasive interventions

Goal: To enhance existing commercially-available passive capsule endoscopes used by clinicians to diagnose gastrointestinal diseases. The first stage of this project is to allow the clinician to control the progress of the capsule along the patient's gastrointestinal tract instead of relying on the body's peristaltic contractions for device propulsion. This is accomplished by using bio-inspired adhesives to stick the capsule to the intestinal lining.

Approach: This work is focused in two primary areas: design and development of the capsule itself and the development of robust, reversible, safe adhesives to reliably anchor the capsule to the gastrointestinal lining. Key components of the capsule include an anchoring mechanism, positioning subsystems, on-board tools, such as for biopsy, and imaging and communication hardware. Preliminary prototypes have used shape memory alloy or micromotors to press adhesive-lined legs into the gastrointestinal lining to anchor the capsule in place. One such prototype is illustrated to the right.

Benefits: Current passive capsule endoscopes are equipped with cameras to image the gastrointestinal tract and provide reliable disease diagnosis in a minimally invasive way. However, because clinicians have no control over the position and orientation of the capsules, there is a chance for missed diagnoses. Allowing the clinician to stop, move and orient the capsule on command would improve diagnostic capabilities by letting the operator take a closer look or backtrack to reexamine a region of interest. Furthermore, once reliable control is obtained, to increase the capabilities of the device, the capsule can be equipped with tools for performing tissue biopsy or for cleaning or cauterizing wound sites. The technology can additionally be adapted to reduce the costs and risks associated with existing upper endoscopic or colonoscopic procedures by eliminating the need for patient sedation.

Media Appearances:

• "The Works: Robots" on the History Channel (September 2008) Link
• Technology Review Article (July 2008)Link
• Name Link

Members: Sehyuk Yim, Metin Sitti

Past Members: Eugene Cheung, Paul Glass


Papers: P. Glass, M. Sitti, A. Pennathur, and R. Appasamy. A Swallowable Tethered Capsule Endoscope for Diagnosing Barrett's Esophagus. Gastrointestinal Endoscopy, 69 (5), p. 106, Apr. 2009.

P. Glass, E. Cheung, and M. Sitti. A legged Anchoring Mechanism for Capsule Endoscopes Using Micropatterned Adhesives. IEEE Transactions on Biomedical Engineering, 55 (12), pp. 2759-2767, Dec. 2008.

P. Glass, E. Cheung, H. Wang, R. Appasamy, and M. Sitti. A Motorized Anchoring Mechanism for a Tethered Capsule Robot Using Fibrillar Adhesives for Interventions in the Esophagus. IEEE BioRob, Scottsdale, AZ, October 2008.

P. Glass, M. Sitti, and R. Appasamy. A New Biomimetic Adhesive for Therapeutic Capsule Endoscope Applications in the Gastrointestinal Tract. Gastrointestinal Endoscopy, 65(5), p. AB 91, Apr. 2007.

M.E. Karagozler, E. Cheung, J. Kwon, and M. Sitti. Miniature endoscopic capsule robot using biomimetic micro-patterned adhesives. IEEE / RAS-EMBS international conference on biomedical robotics and biomechatronics. Pisa, February 2006.

E. Cheung, M.E. Karagozler, S. Park, B. Kim, and M. Sitti. A new endoscopic microcapsule robot using beetle inspired microfibrillar adhesives. Proceedings of the IEEE/ASME international conference on advanced intelligent mechatronics, 551-557, Monterey, July 2005.

J. Kwon, E. Cheung, S. Park, and M. Sitti. Friction enhancement via micro-patterned wet elastomer adhesives on small intestinal surfaces. Biomedical Materials, 1:216-220, 2006.