Biomedical Ultrasonics and Electromagnetics Imaging
Robert McGough | mcgough@egr.msu.edu | www.egr.msu.edu/~fultras-web
Research in the Biomedical Ultrasonics and Electromagnetics Laboratory covers a wide range of emerging applications in therapeutic and diagnostic ultrasound. In particular, we are actively involved in the development of enhanced models and instrumentation for high intensity focused ultrasound (HIFU), histotripsy, B-mode imaging, three-dimensional (3D) ultrasound imaging, ultrasound tomography, plane wave imaging, shear wave imaging, and several other exciting new applications of medical ultrasound.
Numerical Modeling of Medical Ultrasound
We created FOCUS, the ‘Fast Object-oriented C++ Ultrasound Simulator’ to address the need for faster, more accurate, more memory-efficient, and more user-friendly simulation software for medical ultrasound research. FOCUS, which is used at dozens of institutions in the USA for medical ultrasound research and system design, runs in MATLAB and is available for free at http://www.egr.msu.edu/~fultras-web. The development of FOCUS was supported by NIH grants R21 CA121235 (PI: McGough) and R01 EB012079 (PI: McGough).
The foundation of FOCUS is the fast nearfield method and several other algorithms that were developed in the Biomedical Ultrasonics and Electromagnetics Laboratory at MSU. We initially developed FOCUS for ultrasound hyperthermia and HIFU simulations, but we soon found that many of the frequency-domain algorithms that we derived for these applications are readily extendable to time-domain calculations of transient pressure fields and to calculations of intensity fields for shear wave imaging simulations. We have also been developing a new approach for simulating B-mode images with FOCUS. All of these simulations model B-mode images formed by a 192 element linear array with a center frequency of 3 MHz. The Field II simulations sampled at 200 MHz were completed in 79 minutes, the FOCUS simulations sampled at 12 MHz were completed in 11.7 minutes, and the FOCUS simulation results again achieved smaller errors. FOCUS also models nonlinear ultrasound effects for both transient and continuous-wave excitations. Simulations of shear waves generated by an acoustic radiation force in isotropic and anisotropic viscoelastic soft tissue models are also under development.
Medical Ultrasound Technology Development
We are actively developing new technologies for diagnostic and therapeutic applications. We have recently created new ultrasound technology that is expected to have a dramatic impact on all forms of shear wave elastography imaging, including imaging of breast cancer, prostate cancer, thyroid cancer, liver cancer, and many other soft tissue pathologies. We are also developing new ultrasound imaging technology for monitoring lesion formation with laparoscopic HIFU. Some of our other recent technology development efforts include ultrasound tomography and pediatric patient monitoring.
