This book, published by the American Institute of Physics (AIP), is the Conference Proceedings of the 9th International Symposium on Therapeutic Ultrasound that was held 24–26 September 2009 in Aix-en-Provence, France. It gathers 91 articles presented in the symposium addressing fundamental research, technological advancements and challenges, animal studies, and clinical applications of therapeutic ultrasound. The symposium is the annual scientific gathering of the International Society of Therapeutic Ultrasound (ISTU) that was formally established in 2001. Since inception, the ISTU has been experiencing a significant growth that has been witnessed by continued growth in the number of participants in its annual symposia. The 2009 symposium was held with approximately 350 participants many of which were attending for the first time. A large number of students and young researchers attending the symposium will be the key for the future success of therapeutic ultrasound and ISTU as the scientific society that fosters the field. The board of ISTU distributed 5 awards during the 2009 symposium (3 career and 2 student awards). The recipients of the three career awards were Prof. Emeritus Dominique Cathignol, INSERM, Lyon, France, Dr. Elisa Konofagou, Colombia University, New York, USA, and Dr. Mickael Tanter, ESPCI, University of Paris VII, Paris, France. Using ultrasound as an energy-based treatment modality is a fairly old method. First clinical developments of the therapeutic ultrasound date back to mid 19th century when Lynn and colleagues demonstrated first successful application of intensive focused ultrasound in controlled coagulation of soft tissue (Lynn et al., 1942). To date, ultrasound as an energy-based noninvasive therapeutic procedure has found its place in medicine and biology in various modalities including ultrasound hyperthermia for muscle relaxation and pain relief, lithotripsy for kidney and gall bladder stone fragmentations, and HIFU (high intensity focused ultrasound) for malignant and/or nonmalignant tissue ablation. Among them, HIFU procedures when performed under suitable imaging guidance and monitoring has shown very promising attributes as a non-invasive treatment modality. No surprising, a vast majority of papers presented in the meeting and collected in the proceedings book were devoted to the latest research developments around HIFU. The meeting was comprised of 10 plenary and 10 poster sessions that together gives a summary of the latest research and development activities in the field. The sessions cover main areas pertinent to therapeutic ultrasound, in general, and HIFU, in particular, including basic science, technological and engineering aspects, and current and prospect future applications in medicine and biology. An overview of papers presented in this symposium demonstrates an important fact that during past decade the science of therapeutic ultrasound and HIFU have progressed from basic science development and early-phase R&D endeavors to clinical devices and systems that offer treatments in different areas in medicine and biology. In a recent visit to the United States Food and Drug Administration (FDA) office, the reviewer noticed that more than a dozen novel therapeutic ultrasound devices and systems are under FDA approval procedures for various clinical applications. This is also a strong indicator that the field is in a transferring phase from laboratory research to clinical applications. Among others, one of the reasons for this change is the development of modern high-resolution and real-time imaging methods that will allow precise targeting and monitoring of the ultrasound treatments. This will enable noninvasive and high precision interventions that are individualized to each patient’s anatomy and physiology. Two main imaging modalities that are being used for this purpose are ultrasound and MRI. Reviewing papers presented in this book demonstrates the continued dominance of these two imaging modalities as treatment monitoring and guidance methods in the field of therapeutic ultrasound. Although there is much more work to be done before the potential of ultrasound is fully utilized for therapy, the future looks very promising and significant clinical impact is expected in the very near future. It is easy to envision a time in near future when many of the currently invasive procedures will be performed noninvasively and patients who currently have very little hope may be treated and/or cured using ultrasound. As stated above, the significance of clinical aspects of therapeutic ultrasound is quite noticeable at ISTU 2009 and is illustrated in the book by a complete set of four sessions on HIFU-mediated drug delivery, a session on ultrasound surgery in brain and another session fully dedicated to HIFU applications in prostate diseases. Moreover, key lectures in the symposium on treatment monitoring, treatment planning and quality assessment put more emphasize on clinical applications.
In overall, the book gives a valuable collection of the latest research and development papers that covers some of the most important fundamental aspects of the science along with current and prospect future clinical applications of therapeutic ultrasound and HIFU. A rather minor shortcoming of the book is the lack of colors for those figures in which colors could provide additional information and/or help in better interpreting the results. It is suggested allowing having color figures in future proceedings books (possibly with an additional cost to the authors).