Exterminate! Exterminate! Fear not if you hear the cry of the Daleks coming from your bowels one day – scientists have developed a tiny experimental robot as a pain-free exploratory tool for the diagnosis of colo-rectal cancer.
And it’s less a pain in the butt than prevailing methods.
Ordinarily, when symptoms of gastro-intestinal discomfort can’t be otherwise discounted, or blood is found in a stool, patients undergo an invasive colonoscopy.
No more scary snakes
This amounts to having the clinical version of an anaconda – mounted with flashlight and camera – wend its way through your lower intestine, generally while the patient is sedated.
In the vast majority of cases, a colonoscopy is safe, but there are risks of tearing, bleeding (if a polyp is removed) and infection. In the US, where there is no government-funded faecal blood screening for people over 50 – as enjoyed in Australia – colonoscopies are a routine and costly procedure.
That might all change soon
After a decade of work, engineers from the University of Leeds, leading an international consortium of scientists, have demonstrated that it’s technically possible to guide a tiny robotic capsule inside the colon to take micro-ultrasound images.
Known as a Sonopill, the device could one day replace the need for patients to undergo endoscopic examinations.
According to a statement from the university, the Sonopill is a small capsule – with a diameter of 21mm and length of 39mm, which the engineers say can be further scaled down.
The capsule houses a micro ultrasound transducer, an LED light, camera and magnet. A very small flexible cable is tethered to the capsule that also passes into the body via the rectum and sends ultrasound images back to a computer in the examination room.
It works in the lab and in pigs: humans next
The feasibility tests were conducted on laboratory models and in animal studies involving pigs.
Key to the breakthrough was the development of a technique called intelligent magnetic manipulation.
“Based on the principle that magnets can attract and repel one another, a series of magnets on a robotic arm that passes over the patient interacts with a magnet inside the capsule, gently manoeuvring it through the colon,” said the university.
The magnetic forces are harmless and can pass through human tissue, doing away with the need for a physical connection between the robotic arm and the capsule.
“An artificial intelligence system ensures the smooth capsule can position itself correctly against the gut wall to get the best quality micro-ultrasound images,” the university said.
“The feasibility study also showed that in the event the capsule became dislodged, the AI system could navigate it back to the required location.”
The benefits of the robotic invader aren’t confined to greater patient comfort – micro-ultrasound images are better able to identify some types of cell change associated with cancer, effectively providing a no-cut biopsy.
GPs could use these robots during check-ups
“The technology has the potential to change the way doctors conduct examinations of the gastrointestinal tract,” said Professor Pietro Valdastri, Chair in Robotics and Autonomous Systems at the University of Leeds and senior author of the paper.
“The platform is able to localise the position of the Sonopill at any time and adjust the external driving magnet to perform a diagnostic scan while maintaining a high quality ultrasound signal.“
He said this discovery had the potential “to enable painless diagnosis via a micro-ultrasound pill in the entire gastrointestinal tract.”
Sandy Cochran, Professor of Ultrasound Materials and Systems at the University of Glasgow and lead researcher, said the team hoped that “in the near future, the Sonopill will be available to all patients as part of regular medical check-ups, effectively catching serious diseases at an early stage and monitoring the health of everyone’s digestive system.”