Page 16 - Volume 8, Issue 4 - Winter 2012

mechanical or thermal bioeffects. The addition of MR guid- ance and feedback control, in particular, have resulted in a complete system that is capable of depositing energy into the skull in a manner that is both non-ionizing and non-invasive. The developments over the last decade have culminated in clinical trials for chronic neuropathic pain, essential tremor, and the treatment of brain metastasis. For neurosurgical pro- cedures in particular, focused ultrasound enables a same-day alternative to surgery, making potential risky procedures now viable. Furthermore, the use of ultrasound in conjunction with therapeutic agents could potentially allow safe, localised, targeted delivery to the brain. Finally, with the development of more advanced correction algorithms, phased arrays, and multi-channel driving systems, devices will gain an increased ability to precisely target locations within larger steerable volumes and with more power. Continued development will continue to unveil new applica- tions and enable new therapies for the treatment of brain metastasis and central nervous system (CNS) diseases.AT
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12 Acoustics Today, October 2012