Microbubbles decrease the time and acoustic power of ultrasound required to heat and destroy an embedded target, finds research in BioMed Central's open access journal Journal of Therapeutic Ultrasound. If these results can be replicated in the clinic, microbubbles could improve the efficiency of high intensity ultrasound treatment of solid tumors.
High intensity ultrasound is already used to treat solid tumors. Ultrasound can be focused through soft tissue and, because it does not require probes or surgery, is non-invasive. However if the tumor is behind the ribcage or skull, the bone absorbs some of the ultrasound. Consequently the length of treatment needs to be increased, plus there is a potential for heat damage to the bone.
In order to improve ultrasound therapy, especially in these difficult to treat cases, a team from Boston University has developed phase shift nanoemulsions (PSNE), which produce tiny microbubbles when blasted with high intensity ultrasound. Microbubbles smaller than 200nm passively accumulate in tumors and this study shows that microbubbles of this size can amplify the effects of ultrasound in hydrogels designed to mimic solid tumors inside the body.
Holes formed in a predictable manner and with a predictable shape which altered with acoustic intensity. The acoustic intensity and exposure time required for thermal destruction of tumor tissue were both reduced by more than half, compared to ultrasound without microbubbles. The lower power levels and time needed to destroy a target in the presence of microbubbles could potentially improve cancer therapy, especially in hard to reach areas.
The first stage in any new treatment is to show safety and efficacy. Prof Tyrone Porter, who led this study explained, "We used PSNE of phospholipid coated perfluorcarbon which have no known toxicity and have already be shown to be safe clinically. Our technique pushes forward the possible applications of ultrasound therapy in treating solid tumors."
Open access publisher BioMed Central is proud to announce the launch of Journal of Therapeutic Ultrasound in partnership with the Focused Ultrasound Foundation and the International Society for Therapeutic Ultrasound.
"Focused ultrasound technology has enormous potential to improve the quality of lives for millions around the world," noted Neal F. Kassell, M.D., Chairman and Founder of the Focused Ultrasound Foundation. "The research reported in the Journal of Therapeutic Ultrasound will be central to advancing the field and will help accelerate the progress of focused ultrasound towards clinical adoption."
Dr Hilary Glover
Scientific Press Officer, BioMed Central
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Notes to Editors
1. The impact of vaporized nanoemulsions on ultrasound-mediated ablation Peng Zhang, Jonathan A Kopechek and Tyrone M Porter Journal of Therapeutic Ultrasound 1013 1:2 doi:10.1186/2050-5736-1-2
Please name the journal in any story you write. If you are writing for the web, please link to the article. All articles are available free of charge, according to BioMed Central's open access policy.
Please credit image to Peng Zhang, Jonathan A Kopechek and Tyrone M Porter
Image Legend: Processed images showing thermal destruction achieved in tissue-mimicking hydrogel with (left) and without (right) the presence of microbubbles during 7.5-s high-intensity ultrasound exposure. Thermal destruction turns the hydrogel from black to white in the images, which occurred more quickly when microbubbles were formed via PSNE vaporization.
2. Journal of Therapeutic Ultrasound encompasses all aspects of therapeutic ultrasound, namely, the stimulus, inhibition, or modification of tissue function or structure via insonification. This open access, peer-reviewed, online journal focuses mainly on translational and clinical research. The goal is to accelerate the adoption of therapeutic ultrasound as a clinical tool.
3. BioMed Central is an STM (Science, Technology and Medicine) publisher which has pioneered the open access publishing model. All peer-reviewed research articles published by BioMed Central are made immediately and freely accessible online, and are licensed to allow redistribution and reuse. BioMed Central is part of Springer Science+Business Media, a leading global publisher in the STM sector. @BioMedCentral
4. The Focused Ultrasound Foundation was created to improve the lives of millions of people worldwide by accelerating the development and adoption of focused ultrasound therapies. The Foundation works to clear the path to global adoption by coordinating and funding research and educational activities, creating partnerships and fostering collaboration among stakeholders, and building awareness of the technology among patients and professionals. The Foundation is dedicated to ensuring that focused ultrasound finds its place as a mainstream therapy for uterine fibroids, cancer, brain tumors, Parkinson's disease, epilepsy, stroke and other life-threatening conditions within years, not decades. Since its establishment in 2006, the Foundation has become the largest non-governmental source of funding for focused ultrasound research. More information about the Charlottesville, Virginia based Foundation can be found at http://www.