National Center for Scientific Research, Marseille, France.
IEEE Trans Ultrason Ferroelectr Freq Control. 2012 Jul;59(7):1457-69. doi: 10.1109/TUFFC.2012.2346.
Ultrasound tomography has considerable potential as a means of breast cancer detection because it reduces the operator-dependency observed in echography. A half-ring transducer array was designed based on breast anatomy, to obtain reflectivity images of the ductolobular structures using tomographic reconstruction procedures. The 3-MHz transducer array comprises 1024 elements set in a 190-degree circular arc with a radius of 100 mm. The front-end electronics incorporate 32 independent parallel transmit/receive channels and a 32-to-1024 multiplexer unit. The transmit and receive circuitries have a variable sampling frequency of up to 80 MHz and 12-bit precision. Arbitrary waveforms are synthesized to improve the signal-to-noise ratio and to increase the spatial resolution when working with low-contrast objects. The setup was calibrated with academic objects and a needle hydrophone to develop the data correction tools and specify the properties of the system. The backscattering field was recorded using a restricted aperture, and tomographic acquisitions were performed with a pair of 0.08-mm-diameter steel wires, a low-contrast 2-D breast phantom, and a breast-shaped phantom containing inclusions. Data were processed with dedicated correction tools and a pulse compression technique. Objects were reconstructed using the elliptical back-projection algorithm.
超声层析成像技术在乳腺癌检测方面具有很大的潜力，因为它降低了在超声检查中观察到的操作人员依赖性。根据乳房解剖结构设计了一个半环形换能器阵列，以使用层析重建程序获得导管小叶结构的反射率图像。3MHz 的换能器阵列由设置在半径为 100mm 的 190 度圆弧上的 1024 个元件组成。前端电子设备包含 32 个独立的并行发射/接收通道和一个 32 到 1024 的多路复用器单元。发射和接收电路的可变采样频率高达 80MHz 和 12 位精度。任意波形用于提高信噪比，并在处理低对比度物体时提高空间分辨率。该设备使用学术目标物和针状水听器进行校准，以开发数据校正工具并指定系统的特性。使用受限孔径记录反向散射场，并使用一对直径为 0.08mm 的钢丝、一个低对比度的 2D 乳房体模和一个包含夹杂物的乳房形状体模进行层析采集。数据使用专用的校正工具和脉冲压缩技术进行处理。使用椭圆反向投影算法进行物体重建。
