Peralta Laura, Ramalli Alessandro, Reinwald Michael, Eckersley Robert J, Hajnal Joseph V
Department of Biomedical Engineering, School of Biomedical Engineering & Imaging Sciences, King's College London, London SE1 7EH, UK.
Department of Information Engineering, University of Florence, 50139 Florence, Italy.
Appl Sci (Basel). 2020 Oct 29;10(21):7655. doi: 10.3390/app10217655. eCollection 2020 Nov 1.
Transducers with a larger aperture size are desirable in ultrasound imaging to improve resolution and image quality. A coherent multi-transducer ultrasound imaging system (CoMTUS) enables an extended effective aperture through the coherent combination of multiple transducers. In this study, the discontinuous extended aperture created by CoMTUS and its performance for deep imaging and through layered media are investigated by both simulations and experiments. Typical image quality metrics-resolution, contrast and contrast-to-noise ratio-are evaluated and compared with a standard single probe imaging system. Results suggest that the image performance of CoMTUS depends on the relative spatial location of the arrays. The resulting effective aperture significantly improves resolution, while the separation between the arrays may degrade contrast. For a limited gap in the effective aperture (less than a few centimetres), CoMTUS provides benefits to image quality compared to the standard single probe imaging system. Overall, CoMTUS shows higher sensitivity and reduced loss of resolution with imaging depth. In general, CoMTUS imaging performance was unaffected when imaging through a layered medium with different speed of sound values and resolution improved up to 80% at large imaging depths.
在超声成像中，希望使用具有较大孔径尺寸的换能器来提高分辨率和图像质量。相干多换能器超声成像系统（CoMTUS）通过多个换能器的相干组合实现了扩展的有效孔径。在本研究中，通过模拟和实验研究了CoMTUS产生的不连续扩展孔径及其在深度成像和穿透分层介质方面的性能。评估了典型的图像质量指标——分辨率、对比度和对比度噪声比，并与标准单探头成像系统进行了比较。结果表明，CoMTUS的图像性能取决于阵列的相对空间位置。由此产生的有效孔径显著提高了分辨率，而阵列之间的间距可能会降低对比度。对于有效孔径中的有限间隙（小于几厘米），与标准单探头成像系统相比，CoMTUS对图像质量有好处。总体而言，CoMTUS显示出更高的灵敏度，并且随着成像深度分辨率损失降低。一般来说，当通过具有不同声速值的分层介质成像时，CoMTUS的成像性能不受影响，并且在大成像深度处分辨率提高了80%。
