Surgeons are constantly looking for ways of imaging, holding, cutting and repairing diseased tissue while lowering the chance of injury to the patient.
The development of minimally invasive keyhole surgery has done much to reduce post-operative pain, scarring, and the risk of infection. However, surgeons are limited in what they can see and feel, as well as in the range of instruments they can pass through the keyhole.
‘If the tissue can be magnetised in a biocompatible fashion, this opens up therapeutic avenues in dealing with disorders such as small cancers,’ said research leader Prof Sir Alfred Cuschieri of the department of surgery and oncology. ‘When a surgeon touches a tumour with a toothed instrument such as a grasper it can spill cells back into the body.’
It was found that tissue could be magnetised following the discovery of magnetotactic bacteria in 1975. These aquatic organisms make tiny, iron-containing magnetic particles which they use as a compass to align themselves to earth’s geomagnetic field.
The researchers aim to find ways of creating magnetic tissue, as well as measuring the strength of achievable magnetisation.
They believe tissue can be magnetised in one of three ways. The first involves creating surface treatments that are applied to the tissue by mixing a magnetic material with an existing surgical glue. The second involves injecting biologically safe magnetic material directly into the tissue. A final method would use ultrasound or electric fields to force magnetic nanoparticles into the tissue’s cells.
The one-year project is funded by a 110,000 government grant.
The results could aid drug delivery and would allow the creation of a new generation of instruments for endoscopic or keyhole surgery that would enable surgeons to dissect tissues and move them aside without damage. If robots are used to assist surgery, it is also easier to create small electromagnetic robotic components than their mechanical counterparts.
The team has completed preliminary work that indicates it is possible to make tumours respond to magnets.