CRC - MRI-Guided Focused Ultrasound Surgery

Organization: CRC
Publication Date: 26 September 2007
Page Count: 217


The use of acoustic energy for thermal ablation is a relatively old idea. Despite serious attempts by several investigators to develop focused ultrasound surgery into an effective ablative therapy, it has been in the incubation stage as a noninvasive surgical method for a long time. In the last decade, however, since the introduction of monitoring and control by magnetic resonance imaging, remarkable progress has taken place in focused ultrasound surgery.

The goal of this book is to survey this method's extraordinary improvement and advancement when it is integrated with the best diagnostic imaging technique available. Anatomic and functional imaging with magnetic resonance imaging can optimally localize and define targets since magnetic resonance imaging-based thermometry accurately controls energy deposition. The resulting therapy delivery system with closed-loop control-first produced as a commercial product by InSightec, Ltd. (Dallas, Texas, U.S.A.)-is one of the most complex medical devices of our times.

Though we have tried to introduce and present the technique and its applications as completely as possible, a single book on magnetic resonance imaging-guided focused ultrasound surgery cannot adequately cover all recent advances. With that admission, we did detail the technical and physical principles behind the method, explain the biological effects caused by thermal and non-thermal interactions with tissue, and devote a substantial portion of the book to already proven applications, including treatment of uterine fibroids and breast cancer. In addition, we tried to demonstrate the enormous potential of this method for the noninvasive treatment of several malignancies, such as prostate and liver cancer or bone metastasis. Since the most challenging clinical application of focused ultrasound is the ablation of brain tumors, we went into considerable detail in describing this treatment method. Finally, the book discusses such exciting non-thermal applications of magnetic resonance imaging-guided focused ultrasound surgery as targeted drug delivery and gene therapy. We believe that these innovative uses of the technique will have significant clinical impact in the near future.

Targeted delivery of larger molecules into the brain through the transiently opened blood- brain barrier is considered the most promising therapeutic use of magnetic resonance imaging-guided focused ultrasound surgery. This application alone has the potential to drastically change the entire field of clinical neuroscience and neuropharmacology.

Even before this, however, magnetic resonance imaging-guided focused ultrasound surgerywill have significant impact on surgery and radiation oncology. It can be characterized as a "disruptive technology" that will radically change existing medical disciplines. Our vision is that this noninvasive surgical method will eventually replace several invasive surgical procedures and, in some cases, eliminate the need for ionizing radiation.

We believe that this image-guided and controlled technique is safer and more efficient than most of those for open surgery and radiation therapy procedures. However, there is no doubt about the need to further improve the technology in order to advance clinical knowledge and experience.

Although the development of this method originated in academic institutions, it is a very complex technology that must be built with industry involvement. The device, the best example of an advanced image-guided therapy delivery system, requires magnetic resonance imaging to integrate fully with acoustic technology. To accomplish this integration, contributions from General Electric Corporation and InSightec, Ltd. have been critical.

They are not alone. Other medical companies have also become interested in advancing magnetic resonance imaging-guided focused ultrasound surgery.

In the future, specific applications and their clinical success will define the direction of magnetic resonance imaging-guided focused ultrasound surgery. It may consist of the use of high-field magnets with large phased arrays, or it may apply local focused ultrasound surgery probes or applicators. In either case, we believe that magnetic resonance imaging is essential for the technique, not only for providing thermal images but also for accurate targeting and localization. We hope the book elucidates the advantages of magnetic resonance imaging for monitoring and controlling focused ultrasound surgery therapy.

We, the editors, extend our gratitude to the publisher for devoting an entire book to magnetic resonance imaging-guided focused ultrasound surgery-a literary first. To this point, we are very thankful for the opportunity to introduce this exciting technology to a larger audience. We also wish to thank our colleagues who contributed to this book and provided early insight into the development and clinical use of this method. We hope that our collective vision of this technology is correct, and that this initial publication will be followed by several others, each elaborating on magnetic resonance imaging-guided focused ultrasound surgery's full potential.