Jane F Emerson1, David B Chang2, Stuart McNaughton2, Ellen M Emerson3, Stephen A Cerwin4. 1. University of Southern California, Department of Pathology, Los Angeles, California, United States. 2. Magnetus LLC, Irvine, California, United States. 3. University of Southern California, Keck School of Medicine, Los Angeles, California, United States. 4. Southwest Research Institute, Institute Scientist (ret.), San Antonio, Texas, United States.
Abstract
Purpose: Electromagnetic acoustic imaging (EMAI) is a hybrid imaging technique using radio-frequency irradiation to induce ultrasound (US), providing an US image in which spatial conductivity differences provide image contrast. The method is potentially clinically important in that the added diagnostic parameter has been shown to be useful in cancer detection and vascular space delineation. Approach: We report the development of coil configurations and imaging processing techniques designed to address the low signal-to-noise of EMAI and demonstrate achievable resolution and contrast in phantoms along with EMAI signals in excised animal tissue. Experiment results are compared with theoretical calculations. Results: EMAI signal intensities depend on the square of the ampere-turns in the coil radio frequency coil as predicted theoretically. Resolution is shown to be comparable to conventional US imaging with contrast and signal intensity depending on source conductivity. Optimizing signal-to-noise depends on coil design, orientation of the electromagnetic fields, and coherent processing. Conclusions: Two-dimensional EMAI images are shown to have the expected resolution of conventional US with image contrast dependent on conductivity. Achievable signal-to-noise is sufficient to form potentially clinically useful images.
Purpose: Electromagnetic acoustic imaging (EMAI) is a hybrid imaging technique using radio-frequency irradiation to induce ultrasound (US), providing an US image in which spatial conductivity differences provide image contrast. The method is potentially clinically important in that the added diagnostic parameter has been shown to be useful in cancer detection and vascular space delineation. Approach: We report the development of coil configurations and imaging processing techniques designed to address the low signal-to-noise of EMAI and demonstrate achievable resolution and contrast in phantoms along with EMAI signals in excised animal tissue. Experiment results are compared with theoretical calculations. Results: EMAI signal intensities depend on the square of the ampere-turns in the coil radio frequency coil as predicted theoretically. Resolution is shown to be comparable to conventional US imaging with contrast and signal intensity depending on source conductivity. Optimizing signal-to-noise depends on coil design, orientation of the electromagnetic fields, and coherent processing. Conclusions: Two-dimensional EMAI images are shown to have the expected resolution of conventional US with image contrast dependent on conductivity. Achievable signal-to-noise is sufficient to form potentially clinically useful images.
Authors: Jane F Emerson; David B Chang; Stuart McNaughton; Jong Seob Jeong; K K Shung; Stephen A Cerwin Journal: IEEE Trans Ultrason Ferroelectr Freq Control Date: 2013-02 Impact factor: 2.725
Authors: Rosa M S Sigrist; Joy Liau; Ahmed El Kaffas; Maria Cristina Chammas; Juergen K Willmann Journal: Theranostics Date: 2017-03-07 Impact factor: 11.556