ULTRASONIC HIGH RESOLUTION QUANTITATIVE BREAST IMAGING

描述(改编自申请者摘要)：本报告的目的 研究是为了形成高分辨率和定量的超声图像 乳房使用自适应像差矫正和 在逆散射理论中结合一个创新的环 具有可编程传输波形的传感器系统。高分辨率 将形成B超图像，并评估其在 乳腺癌的诊断。成像将采用新的自适应 聚焦技术。在一种技术中，合成发射信号 使用反向传播和时移从散射信号 估算和补偿。合成的波形被预失真 特定的乳房组织路径，从而传播到焦点区域 反转扭曲并产生点和点的未扭曲焦点 对比度分辨率仅受孔径大小和脉冲长度的限制 而不是通过像差。在接收中聚焦使用随后的反向传播 通过时移补偿。在另一种技术中，超声波波前是 在以下四个域之一进行处理：空间、空间频率、时间和 时间频率。正向和反向传播在可选的 距离也被用来改变时间和空间特征 由于信号的时间频率和空间频率特性 波前。在不需要点源的情况下，这两种技术都适用于 在整个传播路径上的不均匀性的影响 换能器和被成像区域。乳房的定量图像 组织内部参数，如声速、可压缩性和 密度将使用图像理论中的重大进步来形成 重建。这些进展产生了最佳的辐射效果，估计 由测量得到的算子的分析得到的散射体特性 散射数据，以及新的图像重建方法。的数据。 高分辨率b超图像和定量图像的构建 将从不同的幻影和大量的乳房样本中获得。这个 生成的图像将与观察到的散射形态进行比较 物体和成像技术将受到严格的评估，因为它们 在乳腺癌检测、诊断和监测中的应用 复发。评估的标准包括点数和对比度。 分辨率、计算简单性和定量图像的能力 显示通过补偿性更改隐藏在b扫描中的新信息 在组织参数中。

DESCRIPTION (Adapted from Applicant's Abstract): The objective of this research is to form high-resolution and quantitative ultrasonic images of the breast using significant advances in adaptive aberration correction and in inverse scattering theory in combination with an innovative ring transducer system that has programmable transmit waveforms. High-resolution b-scan images will be formed and evaluated for their utility in the diagnosis of breast cancer. Image formation will employ new adaptive focussing techniques. In one technique, transmit signals are synthesized from scattered signals using backpropagation followed by time-shift estimation and compensation. The synthesized waveforms are predistorted for the particular breast tissue path so that propagation to the focal zone reverses the distortion and yields an undistorted focus for point and contrast resolution limited only by aperture size and pulse length rather than by aberration. Focussing in reception employs backpropagation followed by time-shift compensation. In another technique, ultrasonic wavefronts are processed in one of four domains: space, spatial frequency, time, and temporal frequency. Forward and backward propagation over a selectable distance is used to change the temporal and spatial characteristics as well as the temporal frequency and spatial frequency characteristics of the wavefront. Without the need for a point source, both techniques correct for the effects of inhomogeneities throughout the propagation path between the transducer and the region being imaged. Quantitative images of breast tissue intrinsic parameters such as sound speed, compressibility, and density will be formed using significant advances in the theory of image reconstruction. The advances yield optimal insonifications, estimation of scatterer properties from analysis of operators derived from measured scattering data, and new image reconstruction methods. Data for the construction of both high-resolution b-scan images and quantitative images will be obtained from various phantoms and numerous breast specimens. The resulting images will be compared with observed morphology of scattering objects and the imaging techniques will be critically evaluated for their utility in breast cancer detection, diagnosis, and monitoring for recurrence. Criteria for this evaluation include point and contrast resolution, computational simplicity, and the ability of quantitative images to show new information that is concealed in b-scans by compensatory changes in tissue parameters.