INTERNAL MEDICINE Scientists have built a micromotor to power fantastic voyages inside the body
In the 1966 science fiction film Fantastic Voyage, scientists shrink a submersible craft, complete with a two-man crew and medical team, to the size of a molecule and inject it into the body of a diplomat to destroy a clot in his brain. In a major step towards that surreal surgical scenario, researchers at Australia’s Monash University have now built and demonstrated the prototype of s motor about twice the width of a human hair. This could one day be used to power a similar microbot small enough to be injected into the human bloodstream in order to scrape plaque off artery walls, transport drug payloads and even extract cells to test for cancer.
Methods of minimally invasive techniques, such as laparoscopic or keyhole surgery and an assortment of operations that use catheters, are already preferred by surgeons and patients alike because of the damage avoided when compared to the open-body scalpel method. But these have their limitations too because damage is not always avoidable. The width of a catheter tube can, for example, in some cases puncture narrow or weakened blood vessels. And cannot reach the delicate narrower channels of the circulatory system such as the labyrinthine arteries of the brain or fine capillaries in the retina.
A freely roving sub-miniature device, on the other hand, would be able to go where no device has gone before-atleast not on its own power. By attaching sensors and cameras and controlling it remotely from the outside doctors would be able to guide it through the narrowest of blood vessels and reach stroke-damage cranial arteries to address blockages in the bloodstream.
Although most of this is still in the future, the Monash team is now working on ways to improve the assembly method and the mechanics which control the micromotors. They have also tested it in human blood and artificial arteries and, later this year, plan to begin experimenting on pigs whose arteries and brains are similar to humans, before proceeding to full-scale human trials. Some day soon older people might not have to wait for a stroke to feel the impact of medical progress; routine microbot check-ups could repair internal damage before the can develop life-threatening consequences.
