超声学.脉冲回波扫描仪.适用于多种传感器类型的灰度医用超声扫描仪的低回波球形模型和性能测试方法

[中文适用范围]： 本文件（技术规范）定义了用于量化实时超声 B 模式扫描仪详细成像性能的术语和方法。细节是通过成像包含组织模拟背景和小型低回波球形目标的模体并分析球形目标的可检测性来评估的。给出了模体属性的规范。此外，还描述了获取图像、进行球形目标可检测性定性分析以及通过探测球体位置并计算其对比噪声比来进行定量分析的程序。通过适当的设计选择，结果可应用于：评估扫描仪配置（扫描仪品牌和型号、扫描头和控制台设置） delineating 肿瘤边界或识别肿瘤特定特征的相对能力；选择最大化空间分辨率的扫描仪控制设置，如频率或发射焦点的数量和位置；检测导致旁瓣增强和虚假回波的探头缺陷。所用探头类型包括：a) 相控阵，b) 线阵，c) 凸阵，d) 机械扇形扫描仪，e) 以 2D 成像模式运行的 3D 探头，以及 f) 以 3D 成像模式运行的 3D 探头（用于有限数量的重建 2D 图像集）。该测试方法适用于工作频率在 1 MHz 至 23 MHz 范围内的探头。 [外文原描述]： IEC TS 62791:2022 defines terms and specifies methods for quantifying detailed imaging performance of real-time, ultrasound B-mode scanners. Detail is assessed by imaging phantoms containing small, low-echo spherical targets in a tissue-mimicking background and analysing sphere detectability. Specifications are given for phantom properties. In addition, procedures are described for acquiring images, conducting qualitative analysis of sphere detectability, and carrying out quantitative analysis by detecting sphere locations and computing their contrast-to-noise ratios. With appropriate choices in design, results can be applied, for example: • to assess the relative ability of scanner configurations (scanner make and model, scan head and console settings) to delineate the boundary of a tumour or identify specific features of tumours; • to choose scanner control settings, such as frequency or the number and location of transmit foci, which maximize spatial resolution; • to detect defects in probes causing enhanced sidelobes and spurious echoes. The types of transducers used with these scanners include: a) phased arrays, b) linear arrays, c) convex arrays, d) mechanical sector scanners, e) 3-D probes operating in 2-D imaging mode, and f) 3-D probes operating in 3-D imaging mode for a limited number of sets of reconstructed 2 D images. The test methodology is applicable for transducers operating in the 1 MHz to 23 MHz frequency range. IEC TS 62791:2022 cancels and replaces the first edition published in 2015. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition. a) It introduces necessary corrections to the analysis methods; these have been published in the literature. b) It increases the range of contrast levels of low-echo spheres in phantoms that meet this Technical Specification. Previous specification was -20 dB, but two additional levels, -6 dB and either -30 dB or, if possible, -40 dB, are now specified. c) It includes a wider range of uses of the methodology, including testing the effectiveness of scanner pre-sets for specific clinical tasks and detecting flaws in transducers and in beamforming. d) It decreases the manufacturing cost by decreasing phantoms' dimensions and numbers of low-echo, backscattering spheres embedded in each phantom.