A novel robotically driven capsule successfully navigated a colon in a pig model in 100% of 30 retroflexion maneuvers, setting the stage for further study of robotics in colonoscopy. The data were presented at the annual Digestive Disease Week.
Although capsule technology has expanded exploration of the GI tract, current capsules are limited by passive movement and lack therapeutic capability, said Keith L. Obstein, MD, of Vanderbilt University in Nashville, Tenn.
The researchers developed a capsule with an 18-mm head and interior permanent magnets designed to be automatically controlled by an external robotic arm in difficult areas.
“Retroflexion is a common but mechanically complex maneuver during colonoscopy, and therefore serves as an excellent subject for autonomous control,” the researchers noted.
Logistically, the capsule is soft-tethered after it is introduced through the rectum, which allows the potential for therapeutic procedures such as biopsies and polyp removal. In addition, the use of an external magnet to pull the robot with the tether may reduce the pressure on the colon that typically created when a physician pushes the colonoscope from behind. Therefore, use of a robotic capsule may help reduce patients’ discomfort and make them more amenable to the procedure, Dr. Obstein said.
In the study, an endoscopist performed the first retroflexion with a standard colonoscope at 15 cm from the anal sphincter, and these parameters were used to set the robotic system for autonomous retroflexion at 15 cm from the anal sphincter.
The success rate was 100% for both the standard endoscope and the automatically controlled robot for each of 30 maneuvers. The average time for a robotic maneuver was 12 seconds, and no leaks or histologic abnormalities were noted.
Studies to evaluate additional control algorithms are in progress, and the robot capsule may be ready for human trials in 2018, Dr. Obstein said.
This study was supported by the National Institute of Biomedical Imaging and Bioengineering of the National Institutes of Health under award number R01EB018992. Dr. Obstein had no relevant financial conflicts to disclose.
Digestive Disease Week® is jointly sponsored by the American Association for the Study of Liver Diseases (AASLD), the American Gastroenterological Association (AGA) Institute, the American Society for Gastrointestinal Endoscopy (ASGE) and the Society for Surgery of the Alimentary Tract (SSAT).