A new and improved non-invasive treatment for brain tumour has been developed by Duke University engineers.
The scientists have designed and built an ultrasound catheter that can fit into large blood vessels of the brain and perform two essential functions.
It can provide real-time moving 3-D images and generate localized temperature increases.
The researchers hope to use this system in conjunction with chemotherapy drugs encased in heat-sensitive microbubbles called liposomes.
"Physicians would inject drug-carrying liposomes into a patient's bloodstream, and then insert a catheter via a blood vessel to the site of the brain tumour," said Carl Herickhoff, fourth-year graduate student at Duke's Pratt School of Engineering and first author of a paper appearing in the journal Ultrasonic Imaging.
"The catheter would use ultrasound to first image the tumour, and then direct a higher-power beam to generate heat at the site, melting the liposome shells and releasing the chemotherapy directly to the tumour.
"The temperature increase would be about four degrees Celsius - enough to melt the liposome, but not enough to damage surrounding tissue. No one has tried this approach before in the brain," he added.
The researchers said that a minimally invasive approach to treating this cancer would be preferable to the conventional methods, which have drawbacks and side effects of their own.
In a series of experiments in animal models and simulated tissues, the researchers demonstrated that they could build a catheter thin enough to be placed in one of the brain's main blood vessels that was capable of serving the dual purpose of visualization and heating.