ERI: Non-Contact Ultrasound Generation and Detection for Tissue Functional Imaging and Biomechanical Characterization

传统的超声成像和传感系统在分辨率和特异性方面存在局限性，通常需要通过耦合介质与被测介质直接接触。然而，在生物医学诊断中，这种直接接触会引起刺激，导致不适。作为科研工具，直接接触往往会导致样品污染或操作不便。为了解决这些问题，该项目旨在开发集成的非接触式超声产生和检测系统，能够实现高分辨率和高度指定的检测和成像，用于生物功能成像和生物力学表征。所开发的非接触式系统可以为科学研究和生物医学界提供一种非常有用的工具，用于非常小范围的特定生化和功能观察。所开发的系统还可以为组织工程界提供一种非接触和非破坏性的方法来表征其发育组织的机械性能。该项目将为本科生和研究生提供研究培训机会，并通过其外展活动促进高中生对科学、技术、工程和数学（STEM）的参与和兴趣。该项目旨在开发和验证利用光声和空气耦合超声技术集成宽带超声产生的系统。这些系统将包括一个紧凑的光纤Sagnac干涉仪，能够进行多波段检测，以适应不同的空间分辨率要求，并能够检测横向超声波，用于生物组织的生物力学特征。这些非接触式超声生成和检测技术的集成将使非接触式组织功能成像具有光学分辨率，以及组织的非接触式生物力学特征。该研究计划是探索紧凑型光纤Sagnac干涉仪在生物组织成像中的潜在应用的第一个系统研究。紧凑型光纤Sagnac干涉仪可以成为增强生物医学诊断和研究的强大、经济和有吸引力的工具，提供更高的准确性和非接触式功能。此外，该项目首次研究了使用紧凑型光纤Sagnac干涉仪在生物组织中进行多波段非接触式光声信号检测的可行性，特别是在高达400MHz的超高频范围内。这一努力的成功可以取代目前昂贵的高频超声检测中基于压电的单换能器。此外，该研究计划引入非接触式空气耦合超声诱导横波来评估心血管路径的生物力学特性，为使用该提出的非接触式超声产生和检测技术进行工程组织力学表征打开大门。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Traditional ultrasound imaging and sensing systems have limitations in resolution and specificity, often requiring direct contact with the medium under investigation through a coupling medium. However, in biomedical diagnosis, this direct contact can cause irritation, resulting in discomfort. As a scientific research tool, direct contact often leads to pollution of samples or inconvenience in operation. To address these issues, this project aims to develop integrated non-contact ultrasound generation and detection systems capable of achieving high-resolution and highly specified detection and imaging for biological functional imaging and biomechanical characterization. The developed non-contact systems can provide the scientific research and biomedical community with a very useful tool for specific biochemical and functional observations at a very small scale. The developed systems can also offer the tissue engineering community a non-contact and non-destructive method for characterizing the mechanical properties of their developed tissues. This project will provide research training opportunities for undergraduate and graduate students and will promote the engagement and interest of high school students in science, technology, engineering and mathematics (STEM) through its outreach activities. This project aims to develop and validate systems that integrate broadband ultrasound generation using both photoacoustic and air-coupled ultrasound techniques. These systems will incorporate a compact fiber optic Sagnac interferometer capable of multiband detection to accommodate different spatial resolution requirements and enable the detection of transverse ultrasound waves for biomechanical characterization of biological tissues. The integration of these non-contact ultrasound generation and detection techniques will enable non-contact tissue functional imaging with optical resolution, as well as non-contact biomechanical characterization of tissues. The research plan represents the first systematic study exploring the potential applications of a compact fiber optic Sagnac interferometer in biological tissue imaging. The compact fiber optic Sagnac interferometer could become a powerful, affordable, and attractive tool for enhancing biomedical diagnosis and research, offering improved accuracy and non-contact capabilities. Additionally, for the first time, this project investigates the feasibility of using the compact fiber optic Sagnac interferometer for multiband non-contact photoacoustic signal detection in biological tissue, particularly, in the ultra-high-frequency range, up to 400MHz. Success in this endeavor could replace the current expensive piezo-based single transducer in high-frequency ultrasound detection. Furthermore, the research plan introduces non-contact air-coupled ultrasound-induced transverse waves to evaluate cardiovascular path biomechanical properties, opening doors for engineered tissue mechanical characterization using this proposed non-contact ultrasound generation and detection technique.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.