SBIR Phase I: Distributed Adaptive Beamforming for Medical Ultrasound Breast Cancer Screening

这项小型企业创新研究（SBIR）第一阶段项目旨在开发一种概念验证分布式信号处理系统，该系统结合了实时自适应波束成形，以提高医学超声成像分辨率和穿透组织的深度。目前使用相控阵的超声成像技术结合了传统的延迟和波束形成技术，以相干地添加来自超声探头的信号。延迟是根据组织中声音的平均速度和给定波束聚焦在组织中的位置的每个传感器元件发出的信号的预期往返时间计算的。固定的延迟导致点扩散，限制了超声信号进入组织的深度，导致选择性差（假阳性），从而影响临床疗效。该项目的目标是开发一种分布式、自适应的波束形成方法，对该方法进行数值评估，开发原型信号处理硬件，证明在少量通道下可以实现实时吞吐量，并证明相关信号处理硬件的可扩展性，从而提高超声成像的灵敏度和选择性。该项目的更广泛影响/商业潜力包括提高图像质量，为2600万乳房x光检查结果显示乳腺组织致密的妇女提供可行的筛查技术。预计将减少漏诊病变（假阴性）的数量，减少假阳性，从而减少基于当前筛查技术进行的不必要活检的数量。早期发现这些妇女的癌症将导致早期干预，挽救生命和降低护理费用，并通过避免放射和化疗而减少侵入性治疗。虽然这项创新最初是针对乳腺成像的超声筛查，但该技术是一个平台，因此商业潜力可以扩展到其他超声程序（例如心脏病学，前列腺癌筛查，血管成像），这些程序也将受益于提高的分辨率和穿透深度。

This Small Business Innovation Research (SBIR) Phase I project seeks to develop a proof-of-concept distributed signal processing system that incorporates real-time adaptive beamforming to increase medical ultrasound imaging resolution and depth of penetration into tissue. Present technology for ultrasound imaging using phased arrays incorporates traditional delay-and-sum beamforming for adding signals from an ultrasound probe coherently. Delays are calculated from an average speed of sound in tissue and the expected round-trip time of a signal emitted by each sensor element given the location in the tissue on which the beam is focused. Fixed delays result in point spread, limiting the depth of penetration of the ultrasound signal into tissue, resulting in poor selectivity (false positives), and thus impacting clinical effectiveness. The objective of this project is to develop a distributed, adaptive approach to beamforming, evaluate the approach numerically, develop prototype signal processing hardware that proves real-time throughput is achievable for a small number of channels, and prove scalability of the associated signal processing hardware to very large arrays thereby increasing sensitivity and selectivity of ultrasound imaging.The broader impact/commercial potential of this project extends from improved image quality, providing a viable screening technology for the 26 million women who have mammographically dense breast tissue. It is expected to reduce the number of missed lesions (false negatives) with fewer false positives therefore reducing the number of unnecessary biopsies performed based on current screening technologies. Early detection of cancer in these women will lead to early interventions, saving lives and reducing cost of care, and requiring less invasive treatment by avoiding radiation and chemotherapy. While the innovation is targeted initially to screening ultrasound for breast imaging, the technology is a platform and thus commercial potential extends to other ultrasound procedures (e.g., cardiology, prostate cancer screening, vascular imaging), which also will benefit from improved resolution and depth of penetration.