Image Processing & Registration
The ability to accurately and reliably model ultrasound beam propagation is a crucial component of MRgFUS research. Modeling patient-specific treatments allows us to examine potential phase aberration effects and ways to correct for those effects, all before actually using the technology in an experiment or with a patient. Accurate acoustic modeling can result in safer and more effective treatments. It is important to be able to accurately model how a focused ultrasound beam propagates through the inhomogeneous tissue structures of the human body. Our lab group has developed a technique known as the hybrid angular spectrum (HAS) technique, which is an extension of the more traditionally used angular spectrum method. HAS can successfully model linear wave propagation and can account for the inhomogeneous structure of human tissues. Our current research is quantitatively validating our acoustic simulation method in ex vivo and in vivo environments and will be integrated into Thermoguide, a MRgFUS clinical treatment environment developed by Image Guided Therapy, Inc.
Almquist, S., Parker, D. L., & Christensen, D. A. (2016). Rapid full-wave phase aberration correction method for transcranial high-intensity focused ultrasound therapies. J Ther Ultrasound, 4(1), 30. doi:10.1186/s40349-016-0074-7Farrer, A. I., Almquist, S., Dillon, C. R., Neumayer, L. A., Parker, D. L., Christensen, D. A., & Payne, A. (2016). Phase aberration simulation study of MRgFUS breast treatments. Medical physics, 43(3), 1374. doi:10.1118/1.494101
Dillon, C. R., Farrer, A., McLean, H., Almquist, S., Christensen, D., & Payne, A. (2018). Experimental assessment of phase aberration correction for breast MRgFUS therapy. Int J Hyperthermia, 34(6), 731-743. doi:10.1080/02656736.2017.142202
Vyas, U., & Christensen, D. (2012). Ultrasound beam simulations in inhomogeneous tissue geometries using the hybrid angular spectrum method. IEEE Trans Ultrason Ferroelectr Freq Control, 59. doi:10.1109/tuffc.2012.230
Johnson, S. L., Dillon, C., Odeen, H., Parker, D., Christensen, D., & Payne, A. (2016). Development and validation of a MRgHIFU non-invasive tissue acoustic property estimation technique. Int J Hyperthermia, 32(7), 723-734. doi:10.1080/02656736.2016.121618
Vyas, U., & Christensen, D. A. (2011). Extension of the angular spectrum method to calculate pressure from a spherically curved acoustic source. J Acoust Soc Am, 130(5), 2687-2693. doi:10.1121/1.362171