Written on Saturday, December 02, 2006 by Gemini
Micro robot that swims up your spine to take pictures of fractures and deliver drugs
A tiny scanning robot that can swim through the body and beam images back to a TV monitor might sound like the plot of a science fiction film.
But such a robot is being developed and researchers hope to inject it into the body through the spinal canal where it will use its inbuilt camera to take images of patients who have suffered trauma, such as a fracture of the spine, or who have tumours. It will also be able to deliver drugs.
The robot will help surgeons plan operations more accurately because they will have a clear image of what is happening in the spinal canal. The device may also be able to take biopsies or tissue samples.
“In the future, micro-robots similar to this will be permanently implanted in our bodies,” says Professor Moshe Shoham, director of the Robotics Laboratory at the Technion-Israel Institute of Technology, where it is being developed. The device – “a swimming endoscope” – is a major advance on what is currently available to examine the spinal canal. Other devices have been developed to examine the colon, including the Pilcam, another Israeli invention, which is a mini camera in a capsule that is swallowed. The images it produces are being used to detect early signs of colon cancer.
The Pilcam travels with the flow of food and waste and does not need a propulsion system. To travel in other parts of the body, however, both propulsion and steering are needed. The new robot has two thin tails or wires protruding from its rear to propel it through the body. Low power electric current from a battery is used to send a travelling wave, like a mini Mexican wave, down the wires.
The movement of the tails makes the capsule ‘swim’. Power to each tail can be varied by remote control so the device can be steered. In the spinal canal – the first target for the device – it will travel through the cerebral spinal fluid, a clear liquid, and send back images in real time for the surgeon to view. “The robot’s propulsion system allows us to go into the spinal canal, blood vessels, etc. The space in the canal is big enough for the device and the fluid is clear like water, which makes it easier to take images,” says Prof Shoham.
The new robot is about 2mm in diameter with a 15mm long micro camera and mini loading bay for drugs, plus a battery and transmitter which can beam the images to a TV screen. Unlike the colon cancer capsule, the new device – which doctors hope to use in two years time – will be injected with special equipment under local anaesthetic into whatever part of the body needs to be inspected.
“It will first be used to transmit images and will help in investigating into patients who have had trauma to the spine, or who have cancer in that area,” says Prof Shoham. “The next stage will be to use the robot to deliver drugs to specific sites of the spinal canal, and in the future it will also be able to perform biopsies and release medications for treatment. “We are also working on modifying the propulsion technology so we can use the device in blood vessels where the fluid velocity is much greater than in the canal,” Shoham said. “When we get it into blood vessels the range of uses will be very great.”