Acoustic Surgery Devices in Clinical Trials

Gail ter Haar’s article “Acoustic Surgery” (Physics Today, Physics Today 0031-9228 54 12 2001 29  https://doi.org/10.1063/1.1445545 December 2001, page 29 ) is admirable in describing bloodless, nonincisional surgery, a goal long desired by medical technology workers. Her description of magnetic resonance–guided focused ultrasound surgery (MRGFUS), however, understates the accomplishments of this approach. With MRGFUS, the focused beam is seen directly at lower power (magnetic resonance imaging can be sensitive to temperature changes of 1–2°C), thus permitting the surgeon to position the treatment beam accurately. MRI is also the most sensitive method for defining the target so that the surgeon can see, for example, tumor margins. Precise closed-loop control of the treatment, without damage to healthy tissue, is thereby obtained. These systems are commercially available, and human clinical trials are under way at multiple sites in the US.