Scientists have used a tiny capsule guided by an external magnet attached to a robotic arm to successfully perform intricate manoeuvres inside the colon, an advance that will reduce discomfort of colonoscopies. Researchers hope that the 18-millimetre capsule robot could be used safely and effectively in the future on humans to identify and remove pre-cancerous lesions and tumours detected during colonoscopy. “There is no doubt in the value of colonoscopies to keep people healthy through preventive screening for colon cancer, but many individuals still avoid this procedure, because of fear of the test itself, perceived discomfort or the risk of sedation,” said Keith Obstein, associate professor at Vanderbilt University Medical Centre in the US.
“We developed this capsule robot to make traversing the GI tract much easier, for both the clinician and patient,” said Obstein. Researchers tested the capsule robot, which has a tether that is smaller in diameter than conventional endoscopes, 30 times in the colon of a pig.
They reported that it successfully completed the manoeuvre of retroflexion, in which it bends backward to give the endoscopist a “reverse-view” of the colon wall, on its own at the press of a button. “Not only is the capsule robot able to actively manoeuvre through the gastrointestinal tract to perform diagnostics, it is also able to perform therapeutic manoeuvres, such as biopsies of tissue or polyp removal, due to the tether – something that other capsule devices are unable to do,” said Obstein.
“Since the external magnet pulls the capsule robot with the tether segment from the front or head of the capsule, instead of a physician pushing the colonoscope from behind as in traditional endoscopy, we are able to avoid much of the physical pressure that is placed on the patient’s colon – possibly reducing the need for sedation or pain medication,” researchers said.
The team found that the autonomously-controlled capsule robot was successful in completing all 30 retroflexions. The capsule robot completed retroflexion in an average of 12 seconds, which was within the researchers’ expectations. Following the success of these tests in a pig, researchers indicated that the team will be pursuing human trials, expected to begin at the end of 2018. In the meantime, his team will continue to optimise the algorithms that control the robotic arm to improve their performance in manoeuvring the capsule-based robotic system.