
Micro-Robot It Looks Like A Toy Spider
This is one of an army of tiny devices designed to travel INSIDE your body to spot and even treat disease.
One of them had legs and ‘to be honest, looked a little scary’ — Professor Pietro Valdastri is describing one of his designs for a miniature robot capable of navigating its way through a human body, one of 20 prototypes he has designed with the potential to diagnose or ‘even cure’ disease.
‘The idea was that the spider robot would be sent into the colon to investigate a [suspicious] growth, and the legs would help to create space to allow the robot to move through — it’s a narrow space,’ says Professor Valdastri, chair of robotics and autonomous systems at Leeds University.
Another of his designs, which looks like a pair of sharp teeth, would carry surgical clips into the body to where needed in order to stem bleeding.
All the tiny robots — known as capsule robots — come equipped with a camera and some also carry a sensor that can detect bleeding or the pH of tissue (which can determine abnormalities, and may give an idea if it’s potentially cancerous).
The capsule robot also needs to carry a tiny radio transmitter capable of sending that information to the outside world — so a surgeon can see in real-time what’s happening — and a receiver, so that it responds to commands to go forward and back, for example.
‘And, ideally, a battery source for power and a reservoir to store drugs,’ adds Professor Valdastri.
‘Then, if something suspicious is detected — either by the robot itself or the doctor — the robot could eject the drug where needed.’
These robots are so small they would be swallowed or inserted via an orifice.
Sounds far-fetched? Actually it’s not: for while the ‘scary’ spider robot hasn’t made it far past the drawing board, another of the Professor’s miniature robots will be tested on human volunteers for the first time next month.
Nor are his designs the only ones in development; in fact, the march of the medical miniature robot appears to be very much under way.
Some zip around the body independently, while others are plugged into a long tether or wire that provides power — but all have the potential to change how we diagnose and treat common conditions, from checking growths to unblocking arteries and even delivering vital medications such as chemotherapy exactly where needed.
The robot being trialled next month is designed to offer a pain-free alternative to a colonoscopy, where a tube with a camera is inserted into the colon to investigate abnormalities.
A colonoscopy takes around 45 minutes and can be unpleasant and uncomfortable, so the patient is normally sedated.
Around 900,000 colonoscopies are performed every year in the UK.
‘Colonoscopy is painful because a stiff tube is inserted into the colon, which has many bends, but the endoscope is not flexible,’ says Professor Valdastri.
The capsule robot, by contrast, is a tiny, cylinder-shaped device measuring 2.5cm by 1.5cm — the size of a broadbean.
‘With this capsule robot it would be painless so the patient wouldn’t even need sedation,’ says Professor Valdastri.
‘It also takes a long time to train someone to carry out a colonoscopy, so there is a lack of capacity. We hope to improve that with our robotic system. The staff would still need training, but for this it is much easier — it’s like learning to play a video game.’
For the human trials, the robot will be pushed via the volunteer’s bottom into the colon.
Attached to a flexible, hollow tether, it will then be ‘driven’ around the colon by a magnetic field controlled by a doctor with a joystick.
‘It races around the colon like a little car, sending live images of what it sees,’ says Professor Valdastri, explaining that its fully rotational camera can be used to look for polyps, small growths that, while generally harmless, can in some cases develop into tumours.
(Who would volunteer for such a thing? Professor Valdastri says he has plenty of offers — ‘many of them who have lost relatives to colon cancer’.)
A study in the journal PLOS One, where researchers analysed incidents involving robotic surgery (where giant spider-like arms are stationed over a patient and moved by a surgeon using a joystick-like device) that had been reported to the official regulator in the U.S., found there had been 144 deaths and 1,391 injuries as a result between 2000 and 2013.
Around 14 per cent of the injuries involved bits falling off the robotic arm and damaging the patient, but 8.6 per cent involved ‘unintended operation of instruments’ — in other words, the robot doing its own thing.
This must surely be one of the biggest fears about mini robots — that they go rogue inside the body.
Each of the experts Good Health spoke to stressed that getting a mini robot approved will involve as many ‘if not more’ safety checks as getting a new drug approved.
But one potential problem, says Carl Heneghan, a professor of evidence-based medicine at the University of Oxford, is that when it comes to regulation there is the potential to fall through the cracks.