We developed a magnetic resonance compatible real-time, three-dimensional imaging ultrasound probe for motion management of radiation therapy for liver cancer. The probe contains an 18,000-element, 46.8 mm × 21.5 mm matrix array constructed from three tiled transducer modules with integrated beamforming ASICs. The center frequency and -6 dB fractional bandwidth of the probe was 3.6 MHz and 85 percent respectively. Ferromagnetic materials in the acoustic stack, flex interconnect and electronics boards were greatly minimized for magnetic resonance compatibility. The probe and cable were shielded to minimize the impact of radiofrequency noise on both the ultrasound and magnetic resonance images. The probe's low-profile, side-viewing design allows it to be strapped to a patient so that images may be acquired hands-free. We present simultaneously acquired ultrasound and 3 Tesla magnetic resonance images with minimal artifacts in both images.

中文翻译：

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磁共振兼容的E4D超声探头，用于放射治疗的运动管理。

我们开发了磁共振兼容的实时三维成像超声探头，用于肝癌放射治疗的运动管理。该探头包含一个18,000个元素，46.8 mm×21.5 mm的矩阵阵列，该矩阵阵列由三个带集成波束形成ASIC的平铺传感器模块构成。探头的中心频率和-6 dB的分数带宽分别为3.6 MHz和85％。声学堆栈，柔性互连和电子板中的铁磁材料已大大减少，以实现磁共振兼容性。探头和电缆被屏蔽以最大程度地减少射频噪声对超声和磁共振图像的影响。探头的低矮侧面观察设计使其可以绑在患者身上，从而可以免提获取图像。