A novel transcranial ultrasound imaging method with diverging wave transmission and deep learning approach

Real time brain transcranial ultrasound imaging is extremely intriguing because of its numerous applications. However, the skull causes phase distortion and amplitude attenuation of ultrasound signals due to its density: the speed of sound is significantly different in bone tissue than in soft tissue. In this study, we propose an ultrafast transcranial ultrasound imaging technique with diverging wave (DW) transmission and a deep learning approach to achieve large field-of-view with high resolution and real time brain ultrasound imaging. DW transmission provides a frame rate of several kiloHz and a large field of view that is suitable for human brain imaging via a small acoustic window. However, it suffers from poor image quality because the diverging waves are all unfocused. Here, we adopted adaptive beamforming algorithms to improve both the image contrast and the lateral resolution. Both simulated and in situ experiments with a human skull resulted in significant image improvements. However, the skull still introduces a wavefront offset and distortion, which degrades the image quality even when adaptive beamforming methods are used. Thus, we also employed a U-Net neural network to detect the contour and position of the skull directly from the acquired RF signal matrix. This approach avoids the need for beamforming, image reconstruction, and image segmentation, making it more suitable for clinical use.

[1]  Debdoot Sheet,et al.  Simulating patho-realistic ultrasound images using deep generative networks with adversarial learning , 2017, 2018 IEEE 15th International Symposium on Biomedical Imaging (ISBI 2018).

[2]  M. O'Donnell,et al.  Coherence factor of speckle from a multi-row probe , 1999, 1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027).

[3]  Hiroshi Kanai,et al.  High-frame-rate echocardiography using diverging transmit beams and parallel receive beamforming , 2011, Journal of Medical Ultrasonics.

[4]  Alfred O. Hero,et al.  Space-alternating generalized expectation-maximization algorithm , 1994, IEEE Trans. Signal Process..

[5]  Stephen W. Smith,et al.  Real-time 3-D contrast-enhanced transcranial ultrasound and aberration correction. , 2008, Ultrasound in medicine & biology.

[6]  K Hynynen,et al.  The potential of transskull ultrasound therapy and surgery using the maximum available skull surface area. , 1999, The Journal of the Acoustical Society of America.

[7]  Thomas Brox,et al.  U-Net: Convolutional Networks for Biomedical Image Segmentation , 2015, MICCAI.

[8]  Ole Marius Hoel Rindal,et al.  The dark region artifact in adaptive ultrasound beamforming , 2017, 2017 IEEE International Ultrasonics Symposium (IUS).

[9]  Purang Abolmaesumi,et al.  A deep learning approach for real time prostate segmentation in freehand ultrasound guided biopsy , 2018, Medical Image Anal..

[10]  Pai-Chi Li,et al.  Adaptive imaging using the generalized coherence factor. , 2003, IEEE transactions on ultrasonics, ferroelectrics, and frequency control.

[11]  B M Asl,et al.  Eigenspace-based minimum variance beamforming applied to medical ultrasound imaging , 2010, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[12]  G. R. Curry,et al.  The acoustic characteristics of the skull. , 1978, Ultrasound in medicine & biology.

[13]  J. Capon High-resolution frequency-wavenumber spectrum analysis , 1969 .

[14]  R C Waag,et al.  Time-shift compensation of ultrasonic pulse focus degradation using least-mean-square error estimates of arrival time. , 1992, The Journal of the Acoustical Society of America.

[15]  K. Hynynen,et al.  Creating brain lesions with low-intensity focused ultrasound with microbubbles: a rat study at half a megahertz. , 2013, Ultrasound in medicine & biology.

[16]  Xin Yang,et al.  Spatio-temporally smoothed coherence factor for ultrasound imaging [Correspondence] , 2014, IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control.

[17]  M Fink,et al.  Adaptive focusing for transcranial ultrasound imaging using dual arrays. , 2006, The Journal of the Acoustical Society of America.

[18]  S.W. Smith,et al.  Phase-aberration correction with a 3-D ultrasound scanner: feasibility study , 2006, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[19]  Mickael Tanter,et al.  Ultrafast Harmonic Coherent Compound (UHCC) Imaging for High Frame Rate Echocardiography and Shear-Wave Elastography , 2016, IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control.

[20]  Mickael Tanter,et al.  Ultrafast imaging in biomedical ultrasound , 2014 .

[21]  G. Seidel,et al.  Harmonic imaging of the human brain. Visualization of brain perfusion with ultrasound. , 2000, Stroke.

[22]  G. Cloutier,et al.  High-Frame-Rate Echocardiography Using Coherent Compounding With Doppler-Based Motion-Compensation , 2016, IEEE Transactions on Medical Imaging.

[23]  Hon Fai Choi,et al.  Comparison of conventional parallel beamforming with plane wave and diverging wave imaging for cardiac applications: a simulation study , 2012, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[24]  Brett Byram,et al.  Deep Neural Networks for Ultrasound Beamforming , 2018, IEEE Transactions on Medical Imaging.

[25]  Jian Li,et al.  On robust Capon beamforming and diagonal loading , 2003, IEEE Trans. Signal Process..

[26]  J. Camacho,et al.  Phase Coherence Imaging , 2009, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[27]  Mehdi Hajian,et al.  Reconstruction and Analysis of Ultrasound Images for Transcranial Ultrasound Applications , 2016 .

[28]  M. O’Donnell,et al.  Phase-aberration correction using signals from point reflectors and diffuse scatterers: basic principles , 1988, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[29]  Elodie Tiran,et al.  Transcranial Functional Ultrasound Imaging in Freely Moving Awake Mice and Anesthetized Young Rats without Contrast Agent , 2017, Ultrasound in medicine & biology.

[30]  B. M. Shield,et al.  DEVELOPMENT OF A RAY TRACING COMPUTER MODEL FOR THE PREDICTION OF THE SOUND FIELD IN LONG ENCLOSURES , 2000 .

[31]  Austin Reiter,et al.  A Deep Learning Based Alternative to Beamforming Ultrasound Images , 2018, 2018 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP).

[32]  Roman Gr. Maev,et al.  Development of a method to image blood flow beneath the skull or tissue using ultrasonic speckle reflections , 2013, Medical Imaging.

[33]  István Csabai,et al.  Detecting and classifying lesions in mammograms with Deep Learning , 2017, Scientific Reports.

[34]  Geoffrey E. Hinton,et al.  Rectified Linear Units Improve Restricted Boltzmann Machines , 2010, ICML.

[35]  Geoffrey E. Hinton,et al.  ImageNet classification with deep convolutional neural networks , 2012, Commun. ACM.

[36]  J. Sethian,et al.  Fast methods for the Eikonal and related Hamilton- Jacobi equations on unstructured meshes. , 2000, Proceedings of the National Academy of Sciences of the United States of America.