Assessment of the safety and efficacy of microbubble exposure in diagnostic and therapeutic ultrasound

Lead Research Organisation: Institute of Cancer Research
Department Name: Division of Radiotherapy and Imaging

Abstract

Gas microbubbles coated with a surfactant or polymer shell have become well established as the most effective form of contrast agent for diagnostic ultrasound imaging. More recently, the use of coated microbubbles in therapeutic applications such as targeted drug delivery has also become an active area of research. However, their behaviour in vivo is by no means fully understood and the aim of this project is to investigate the hitherto neglected problem of microbubbles excited by an ultrasound field within the confines of narrow blood vessels. The work will involve a combination of theoretical modelling and both in vitro and in vivo experiments which will enable a more rigorous assessment of the safety of ultrasound contrast agents and the development of more effective ultrasound therapies.

Publications

10 25 50
 
Description In this project a novel system for the ultrasound exposure of isolated, cannulated arteries has been developed to allow study of the effects of both therapeutic and diagnostic ultrasound exposure of vessels with and without ultrasound imaging contrast agent (microbubbles) within the vessels. The system allows microscopy imaging of the vessel throughout the experiment and passive detection of acoustic cavitation during the ultrasound exposure. The application of standard vessel vitality tests, combined with histological investigation of the microscopic damage to the vessel components has demonstrated how acoustic cavitation in the presence of ultrasound contrast greatly enhances the risk and extent of vascular damage.
Exploitation Route These results should contribute to the understanding of the safe application of diagnostic and therapeutic ultrasound, and thus decrease any risk to patients. This research has greatly improved understanding of the interaction of ultrasound with blood vessels. This is particularly important when considering the safety of diagnostic ultrasound scans in patients for whom contrast agent enhancing imaging is medically indicated. This also offers a unique and extremely useful platform for on going studies. Information from this study will also be fed into treatment planning software being developed using EPSRC funding (EP/F029217/1).
Sectors Education

Healthcare

 
Title in vessel bubble imaging 
Description We have a microscopy system that allows visualisation of bubbles in vessels while under ultrasound exposure 
Type Of Material Model of mechanisms or symptoms - mammalian in vivo 
Year Produced 2010 
Provided To Others? No  
Impact This will allow the action of bubbles in medical ultrasound fields to be studied. This is important for diagnostic ultrasound safety, and also for optimising ultrasound enhanced drug delivery strategies 
 
Description Imperial College 
Organisation Imperial College London
Department Department of Chemical Engineering
Country United Kingdom 
Sector Academic/University 
PI Contribution We co-supervise a student working on the effects of acoustic streaming set up by single bubbles on blood vessel walls. Much of the experimental work is carried out at ICR
Collaborator Contribution Imperial College is funding the research, and leading the theoretical aspects of this work
Impact presentations at informal seminars
Start Year 2017
 
Description Isolated vessel study 
Organisation University College London
Country United Kingdom 
Sector Academic/University 
PI Contribution We performed the experimental part of this study
Collaborator Contribution UCL performed the theoretical aspects to support experiments
Impact Papers, conference presentations
Start Year 2007
 
Description NPL 
Organisation National Physical Laboratory
Country United Kingdom 
Sector Academic/University 
PI Contribution We carried out the major part of this project, developing measurement methods
Collaborator Contribution NPL contributed advice and expertise to help develop measurement methods
Impact Papers, conference presentations
Start Year 2007