Injectable agents for the detection and treatment of cancer by ultrasound
The Institut Langevin has developed an expertise on the manipulation of waves to improve ultrasound therapy within the brain, measure the elasticity of tissue and perform functional brain imaging. My particular field is concerned with injectable agents that are used to improve the capabilities of ultrasound for both therapy and diagnostic. Microbubbles, for instance, are already injected in patients to enhance the contrast from blood vessels in ultrasonic imaging. Our group has developed several techniques to improve their contrast, but also to localize them with resolutions much beyond the diffraction limit (wavelength/2). In this context, I will also discuss new methods for molecular imaging, which can be used to highlight the biological process underlying cancer progression.
In a second part, I will present the use of injectable agents for the treatment of localized disease. Because of their ubiquity and depth of penetration, ultrasound can become an excellent tool to deliver therapeutic dose in a specific region while preserving healthy tissue. One of the methods I will present is to create drugs that are only active within the focal region of the ultrasound beam by exploiting the concept of sonoporation. Another possibility is to deliver large payloads of markers or drugs with the millimetric spatial resolution and microsecond time resolution allowed by an ultrasonic scanner. The method exploits composite droplets developed jointly with the MMN since 2008. On that basis, our collaboration has also introduced the concept of chemistry in-situ which could generate the drugs themselves within the tissue to be treated. We hope that these approaches would eventually allow radiologists to treat rapidly, and without side-effects, focal diseases previously considered incurable.