Song Hyunwoo, Kang Jeeun, Boctor Emad M
Department of Computer Science, Whiting School of Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA.
Laboratory for Computational Sensing and Robotics, Whiting School of Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA.
J Comput Des Eng. 2022 Aug 24;9(5):1852-1865. doi: 10.1093/jcde/qwac083. eCollection 2022 Oct.
In this paper, we present a novel design framework of synthetic radial aperture focusing for three-dimensional (3D) transrectal ultrasound imaging (TRUS-rSAF), in which multiple transmittance/reception events at different scanning angles are synthesized to reconstruct a radial plane in the target volume, securing high spatial resolution and texture uniformity. A theory-based design approach has not been available to push the envelope of the 3D rSAF technique. Herein, a closed-form analytical description of the TRUS-rSAF method is presented for the first time, effectively delineating spatial resolution and grating lobe positions in the radial dimension of a TRUS transducer. We demonstrate a solid optimization workflow based on the theoretical foundation to improve its spatiotemporal resolution, grating lobe artifacts, and signal-to-noise ratio. A specific design criterion was considered to outperform a clinical 3D TRUS imaging as a reference (TRUS-REF), where each radial plane is reconstructed with a single transmittance/reception event using a motorized actuator. The optimized TRUS-rSAF method significantly enhanced spatial resolution up to 50% over the TRUS-REF method while providing clinically effective temporal resolution (2-8 volume/sec) with negligible grating lobe artifacts. The results indicate that the proposed design approach would enable a novel TRUS imaging solution in clinics.
在本文中，我们提出了一种用于三维（3D）经直肠超声成像（TRUS - rSAF）的合成径向孔径聚焦的新颖设计框架，其中在不同扫描角度的多个透射/接收事件被合成以重建目标体积中的径向平面，确保高空间分辨率和纹理均匀性。此前尚无基于理论的设计方法来推动3D rSAF技术的发展。在此，首次给出了TRUS - rSAF方法的闭式解析描述，有效地描绘了经直肠超声换能器径向维度上的空间分辨率和旁瓣位置。我们基于该理论基础展示了一个可靠的优化工作流程，以提高其时空分辨率、旁瓣伪像和信噪比。考虑了一个特定的设计标准，以优于作为参考的临床3D经直肠超声成像（TRUS - REF），其中每个径向平面是使用电动致动器通过单个透射/接收事件重建的。优化后的TRUS - rSAF方法比TRUS - REF方法显著提高了高达50%的空间分辨率，同时提供了临床上有效的时间分辨率（2 - 8体积/秒），且旁瓣伪像可忽略不计。结果表明，所提出的设计方法将为临床提供一种新颖的经直肠超声成像解决方案。
