Researchers have successfully dragged small magnetic beads through the arteries of live pigs using the magnets of an MRI scanner and some custom software. Eventually this technique could be used to move small medical devices through human bodies, making even keyhole surgery seem invasive.

The experiment involved steering a 1.5-millimetre-diameter magnetic bead back and forth through the carotid artery of a live pig, at up to 10 centimetres per second - you can see a video here.

Custom software was created that uses the MRI’s three scanning coils to steer magnetic objects around by applying magnetic gradients to move the object along a chosen path. It scans the object’s location 24 times a second and continuously alters the power supply to each electro-magnetic coil to keep it on course.

Matthew Sparkes is a contributing author for MoT.