Miniature ultrasound probes for diagnostic imaging in the esophagus

在临床环境中常规使用的超声技术在广泛的应用中使用标准配置的设备。虽然这对于使用体外探头的常规成像是足够的，但仍然有许多临床设置不能满足当前标准配置和图像分辨率的要求，例如，用于诊断和指导干预的食管壁成像。这项研究计划解决了在制造微型探头和实施组织弹性成像技术以进行食道显微超声(高分辨率)成像方面的工程和科学挑战。 使用高频换能器阵列的微超声成像由于波长较短而提供了更好的分辨率，但代价是衰减增加和图像深度降低。这种取舍可以通过在感兴趣的部位放置一个微型超声探头来克服，在这种情况下，放置一个微型换能器阵列，通过6 mm的内窥镜端口并定位为对食管壁进行成像。微型微型超声探头之所以成为可能，是因为器件的尺寸随着波长的变化而变化，但微尺度的尺寸带来了制造方面的挑战。常规成像频率下的超声弹性成像现在被常规用于检测组织中的损伤。为了使高分辨率弹性成像具有令人满意的信噪比，必须克服用于测量组织硬度的压缩脉冲的衰减增加。 我们的假设是，使用高性能的压电晶体复合材料来增加微型高频阵列的输出功率，结合先进的电气互连技术，可以最大限度地减少探头中互连和布线占用的体积，从而克服这些挑战。 这项研究计划的具体目标是： 1.制造集成到内窥镜探头中的微型微型超声换能器阵列 2.利用微超声探头实现高分辨率超声弹性成像技术测量组织硬度 这项研究的长期目标是开发一种制造微型超声探头和组织表征技术的平台技术，并有可能在生物医学成像的许多应用中采用。

Ultrasound technologies used routinely in clinical contexts employ standard configurations of devices for a broad range of applications. While this is sufficient for conventional imaging using extracorporeal probes, there are remain many clinical settings for which the current standard configurations and image resolution are unsatisfactory, for example, imaging the esophageal wall for diagnosis and guiding intervention. This research programme addresses the engineering and scientific challenges in creating miniaturised probes and implementing tissue elastography techniques for micro-ultrasound (high resolution) imaging of the esophagus. Micro-ultrasound imaging, using high frequency transducer arrays, affords better resolution because of the shorter wavelength, but at the cost of increased attenuation and decreased image depth. This trade-off can be overcome by placing a micro-ultrasound probe at the site of interest, in this case, a miniaturised transducer array that fits through a 6-mm endoscope port and positioned to image the wall of the esophagus. Miniature micro-ultrasound probes become possible because device dimensions scale with the wavelength, but the micro-scale dimensions introduce fabrication challenges. Ultrasound elastography at conventional imaging frequencies is now routinely used for detecting lesions in tissue. In order for high resolution elastography to have satisfactory signal-to-noise ratio, the increased attenuation of the compressing pulses used to measuring tissue stiffness must be overcome. Our hypothesis is that these challenges can be overcome using high performance piezocrystal composites to increase output power from miniature high frequency arrays, combined with advanced electrical interconnect technique that minimise the volume occupied by the interconnects and cabling in a probe. The specific aims of this research programme are: 1. To create miniature, micro-ultrasound transducer arrays integrated into endoscopic probes 2. To implement high resolution ultrasound elastography techniques for measuring tissue stiffness with the micro-ultrasound probes The long term goal of the research is to develop a platform technology for fabrication of miniature ultrasound probes and tissue characterisation techniques, with potential for adoption across many applications in biomedical imaging.