The Main Event
« More from the exhibit hall | Main | Imaging biomarkers come to the fore »
Quote of the day
17:34 Monday CT:
“The g-force [felt by a CT source during a scan] is larger than that felt by the space shuttle during take off.”
This interesting fact was produced by Otto Zhou, a professor at the University of North Carolina at Chapel Hill (Chapel Hill, NC), during the “Advances in X-ray imaging” symposium this afternoon. He was making the point that there is not much room for improving the temporal resolution of CT with current technology. This is because it relies on the mechanical rotation of large X-ray tubes, and Newtonian mechanics limits how fast that can practically be done.
Not surprisingly, he has a solution to offer. Perhaps slightly more surprising is the fact that it comes in the form of carbon nanotubes (CNTs). While these are being touted as a wonder material for their strength, toughness and electrical properties, it is hard to envisage them producing X-rays powerful enough for medical imaging.
Thanks to a phenomenon known as field emission, however, they can, and Zhou claimed that CNT-based X-ray sources would have several advantages over conventional technology. As well as being smaller and lighter, each nanotube would produce its own focal spot. This would allow for a source array that could surround the whole patient, meaning no mechanical motion would be needed and temporal resolution could be improved significantly.
As if that isn’t enough, Zhou also thinks his nanotubes will one day form the basis of a novel radiation-therapy system. What’s more, CNT-based microirradiation systems developed at the University of North Carolina are already contributing to radiobiological research, as medicalphysicsweb reported last year. Check out Nanotubes shed light on cancer therapies for the full story.
