A significant part of the activities of the MSDLab in the field of ultrasound imaging is well related to the recent development of the ULA-OP system. The full programmability of the transmission-reception chain of the ULA-OP has pushed the development of advanced applications. Significant contributions of the lab in this field include:

 

Development of methods for improved ultrasound imaging

• to enhance image quality (e.g., spatio-temporal resolution, signal-to-noise ratio, contrast, penetration depth) by advanced beamforming and reconstruction algorithms based on high frame rate sequences (plane/diverging waves or multiline transmissions), coded excitation, and super-resolution.
• to accelerate the application of medical (cardiac, vascular, functional) imaging by developing novel techniques in the fields of tissue/vector Doppler, speckle tracking, non-linear (harmonic) imaging, strain estimation.

Example of experimental transmitted beam patterns for multiline transmission imaging

• E. Boni et al., “A reconfigurable and programmable FPGA-based system for nonstandard ultrasound methods,” IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, vol. 59, no. 7, pp. 1378–1385, Jul. 2012, doi: 10.1109/TUFFC.2012.2338.
• A. Ramalli, O. Basset, C. Cachard, E. Boni, and P. Tortoli, “Frequency-domain-based strain estimation and high-frame-rate imaging for quasi-static elastography,” Ultrasonics, Ferroelectrics and Frequency Control, IEEE Transactions on, vol. 59, no. 4, pp. 817–824, Apr. 2012, doi: 10.1109/TUFFC.2012.2260.
• E. Boni, A. Cellai, A. Ramalli, and P. Tortoli, “A high performance board for acquisition of 64-channel ultrasound RF data,” in Ultrasonics Symposium (IUS), 2012 IEEE International, 2012, pp. 2067–2070, doi: 10.1109/ULTSYM.2012.0517.
• F. Varray, O. Basset, P. Tortoli, and C. Cachard, “CREANUIS: A Non-linear Radiofrequency Ultrasound Image Simulator,” Ultrasound in Medicine and Biology, vol. 39, no. 10, pp. 1915–1924, Oct. 2013, doi: 10.1016/j.ultrasmedbio.2013.04.005.
• A. Iula et al., “An enhanced ultrasound technique for 3D palmprint recognition,” in Ultrasonics Symposium (IUS), 2013 IEEE International, Jul. 2013, pp. 978–981, doi: 10.1109/ULTSYM.2013.0251.
• L. Demi, J. Viti, L. Kusters, F. Guidi, P. Tortoli, and M. Mischi, “Implementation of parallel transmit beamforming using orthogonal frequency division multiplexing-achievable resolution and interbeam interference,” IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, vol. 60, no. 11, pp. 2310–2320, Nov. 2013, doi: 10.1109/TUFFC.2013.6644735.
• M. Lenge, A. Ramalli, E. Boni, H. Liebgott, C. Cachard, and P. Tortoli, “High-frame-rate 2-D vector blood flow imaging in the frequency domain,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, vol. 61, no. 9, pp. 1504–1514, Sep. 2014, doi: 10.1109/TUFFC.2014.3064.
• L. Tong, A. Ramalli, R. Jasaityte, P. Tortoli, and J. D’hooge, “Multi-Transmit Beam Forming for Fast Cardiac Imaging: Experimental Validation and In Vivo Application,” IEEE Transactions on Medical Imaging, vol. 33, no. 6, pp. 1205–1219, Jun. 2014, doi: 10.1109/TMI.2014.2302312.
• L. Demi, A. Ramalli, G. Giannini, and M. Mischi, “In Vitro and in Vivo tissue harmonic images obtained with parallel transmit beamforming by means of orthogonal frequency division multiplexing,” Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on, vol. 62, no. 1, pp. 230–235, Jan. 2015, doi: 10.1109/TUFFC.2014.006599.
• M. Toulemonde, O. Basset, P. Tortoli, and C. Cachard, “Thomson’s multitaper approach combined with coherent plane-wave compounding to reduce speckle in ultrasound imaging,” Ultrasonics, vol. 56, pp. 390–398, Feb. 2015, doi: 10.1016/j.ultras.2014.09.006.
• L. Tong et al., “Wide-Angle Tissue Doppler Imaging at High Frame Rate Using Multi-Line Transmit Beamforming: An Experimental Validation In Vivo,” IEEE Transactions on Medical Imaging, vol. 35, no. 2, pp. 521–528, Feb. 2016, doi: 10.1109/TMI.2015.2480061.
• G. Matrone, A. Ramalli, A. S. Savoia, P. Tortoli, and G. Magenes, “High Frame-Rate, High Resolution Ultrasound Imaging With Multi-Line Transmission and Filtered-Delay Multiply And Sum Beamforming,” IEEE Transactions on Medical Imaging, vol. 36, no. 2, pp. 478–486, Feb. 2017, doi: 10.1109/TMI.2016.2615069.
• G. Zurakhov et al., “Multiline Transmit Beamforming Combined With Adaptive Apodization,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, vol. 65, no. 4, pp. 535–545, Apr. 2018, doi: 10.1109/TUFFC.2018.2794219.
• G. Matrone, A. Ramalli, P. Tortoli, and G. Magenes, “Experimental evaluation of ultrasound higher-order harmonic imaging with Filtered-Delay Multiply And Sum (F-DMAS) non-linear beamforming,” Ultrasonics, vol. 86, pp. 59–68, May 2018, doi: 10.1016/j.ultras.2018.01.002.
• G. Matrone and A. Ramalli, “Spatial Coherence of Backscattered Signals in Multi-Line Transmit Ultrasound Imaging and Its Effect on Short-Lag Filtered-Delay Multiply and Sum Beamforming,” Applied Sciences, vol. 8, no. 4, p. 486, Mar. 2018, doi: 10.3390/app8040486.
• S. Harput et al., “3-D Super-Resolution Ultrasound Imaging With a 2-D Sparse Array,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, vol. 67, no. 2, pp. 269–277, Feb. 2020, doi: 10.1109/TUFFC.2019.2943646.
• S. Rossi, A. Ramalli, F. Fool, and P. Tortoli, “High-Frame-Rate 3-D Vector Flow Imaging in the Frequency Domain,” Applied Sciences, vol. 10, no. 15, Art. no. 15, Jan. 2020, doi: 10.3390/app10155365.
• L. Peralta, A. Ramalli, M. Reinwald, R. J. Eckersley, and J. V. Hajnal, “Impact of Aperture, Depth, and Acoustic Clutter on the Performance of Coherent Multi-Transducer Ultrasound Imaging,” Applied Sciences, vol. 10, no. 21, Art. no. 21, Jan. 2020, doi: 10.3390/app10217655.
• M. Orlowska, A. Ramalli, S. Bézy, V. Meacci, J.-U. Voigt, and J. D’hooge, “In-Vivo Comparison of Multiline Transmission and Diverging Wave Imaging for High Frame Rate Speckle Tracking Echocardiography,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, pp. 1–1, 2020, doi: 10.1109/TUFFC.2020.3037043.
• A. Ramalli, A. Rodriguez-Molares, J. Avdal, J. D’hooge, and L. Løvstakken, “High-Frame-Rate Color Doppler Echocardiography: A Quantitative Comparison of Different Approaches,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, vol. 67, no. 5, pp. 923–933, May 2020, doi: 10.1109/TUFFC.2019.2958031.

 

Real-time implementation and test of innovative imaging methods to produce (compounded) images at high-frame-rate, for application to cardiac imaging, vector Doppler and color flow mapping

• P. Tortoli, A. Dallai, E. Boni, L. Francalanci, and S. Ricci, “An Automatic Angle Tracking Procedure for Feasible Vector Doppler Blood Velocity Measurements,” Ultrasound in Medicine & Biology, vol. 36, no. 3, pp. 488–496, Mar. 2010, doi: 10.1016/j.ultrasmedbio.2009.11.004.
• A. Ramalli et al., “Real-time implementation of a novel algorithm for ultrasound freehand elastography of breast lesions,” in 2014 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), May 2014, pp. 5158–5161, doi: 10.1109/ICASSP.2014.6854586.
• A. Ramalli, F. Guidi, E. Boni, and P. Tortoli, “A real-time chirp-coded imaging system with tissue attenuation compensation,” Ultrasonics, vol. 60, pp. 65–75, Jul. 2015, doi: 10.1016/j.ultras.2015.02.013.
• E. Boni et al., “ULA-OP 256: A 256-Channel Open Scanner for Development and Real-Time Implementation of New Ultrasound Methods,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, vol. 63, no. 10, pp. 1488–1495, Oct. 2016, doi: 10.1109/TUFFC.2016.2566920.
• A. Ramalli, E. Boni, A. Dallai, F. Guidi, S. Ricci, and P. Tortoli, “Coded Spectral Doppler Imaging: From Simulation to Real-Time Processing,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, vol. 63, no. 11, pp. 1815–1824, Nov. 2016, doi: 10.1109/TUFFC.2016.2573720.
• F. Guidi, A. Dallai, E. Boni, A. Ramalli, and P. Tortoli, “Implementation of color-flow plane-wave imaging in real-time,” in 2016 IEEE International Ultrasonics Symposium (IUS), Sep. 2016, pp. 1–4, doi: 10.1109/ULTSYM.2016.7728803.
• E. Boni et al., “Architecture of an Ultrasound System for Continuous Real-Time High Frame Rate Imaging,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, vol. 64, no. 9, pp. 1276–1284, Sep. 2017, doi: 10.1109/TUFFC.2017.2727980.
• A. Ramalli et al., “High dynamic range ultrasound imaging with real-time filtered-delay multiply and sum beamforming,” in 2017 IEEE International Ultrasonics Symposium (IUS), Sep. 2017, pp. 1–4, doi: 10.1109/ULTSYM.2017.8092339.
• S. Ricci, J. Wiklund, and V. Meacci, “Real-time staggered PRF for in-line industrial fluids characterization,” in 2017 IEEE International Ultrasonics Symposium (IUS), Sep. 2017, pp. 1–1, doi: 10.1109/ULTSYM.2017.8091778.
• A. Dolet et al., “An Open Real-Time Photoacoustic Imaging Scanner,” in 2018 IEEE International Ultrasonics Symposium (IUS), Oct. 2018, pp. 1–3, doi: 10.1109/ULTSYM.2018.8580028.
• S. Ricci, A. Ramalli, L. Bassi, E. Boni, and P. Tortoli, “Real-Time Blood Velocity Vector Measurement Over a 2-D Region,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, vol. 65, no. 2, pp. 201–209, Feb. 2018, doi: 10.1109/TUFFC.2017.2781715.
• A. Ramalli et al., “Real-Time High-Frame-Rate Cardiac B-Mode and Tissue Doppler Imaging Based on Multiline Transmission and Multiline Acquisition,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, vol. 65, no. 11, pp. 2030–2041, Nov. 2018, doi: 10.1109/TUFFC.2018.2869473.
• V. Meacci et al., “FPGA-based multi cycle parallel architecture for real-time processing in ultrasound applications,” Lecture Notes in Electrical Engineering, vol. 550, no. 9783030119720, pp. 295–301, 2019, doi: 10.1007/978-3-030-11973-7_34.
• F. Guidi, A. Dallai, and P. Tortoli, “Continuous-time High-Pass filtering for real-time HFR Color Flow Imaging,” in 2020 IEEE International Ultrasonics Symposium (IUS), Sep. 2020, pp. 1–3, doi: 10.1109/IUS46767.2020.9251698.
• S. Rossi et al., “Real-Time System for High Frame Rate Vector Flow Imaging,” in 2020 IEEE International Ultrasonics Symposium (IUS), Sep. 2020, pp. 1–4, doi: 10.1109/IUS46767.2020.9251328.
• A. Ramalli et al., “High-Frame-Rate Tri-Plane Echocardiography With Spiral Arrays: From Simulation to Real-Time Implementation,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, vol. 67, no. 1, pp. 57–69, Jan. 2020, doi: 10.1109/TUFFC.2019.2940289.
• A. Ramalli et al., “Real-time 3-D Spectral Doppler Analysis with a Sparse Spiral Array,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, vol. early access, 2021, doi: 10.1109/TUFFC.2021.3051628.
• F. Guidi and P. Tortoli, “Real-Time High Frame Rate Color Flow Mapping,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, vol. Accepted for publication, 2021.