NSF/FDA SIR: Morphologically Complex Tissue-Mimicking Phantoms for Evaluating Tissue Scattering Artifacts in Photoacoustic Imaging

NSF/FDA SIR：形态复杂的组织模拟体模，用于评估光声成像中的组织散射伪影

• 批准号: 1937674
• 负责人: Jesse Jokerst
• 金额: $ 20万
• 依托单位: University of California-San Diego
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-12-01 至 2022-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1937674&HistoricalAwards=false
• 关键词: NSF; FDA; SIR; Morphologically; Complex

NON-TECHNICAL ABSTRACT:Ultrasound is a powerful tool to image diseases including cancer, orthopedic disorders, and heart function. One limitation of ultrasound is that it suffers from low contrast (contrast is the difference in signal intensity between the region of interest and the background tissue). Therefore, there is a large body of research into a special kind of ultrasound known as photoacoustic imaging. Photoacoustic imaging uses light to generate sound only in the area of interest-this increases the contrast. Unfortunately, photoacoustic ultrasound is not yet approved for widespread use in people. This might be partially due to a lack of devices and methods to validate and standardize the novel imaging equipment needed for photoacoustic imaging. Therefore, this work will create specialized plastic objects with known optical and acoustic properties suitable for calibrating and standardizing photoacoustic imaging equipment. This proposal combines expertise from academia and the Food and Drug Administration to identify materials that have optical and acoustic properties similar to human tissue. We will create test objects and methods that will be useful to instrument manufacturers and physicians. The resulting test objects will improve knowledge of how to best create photoacoustic imaging instrumentation and might also streamline regulatory approval of this equipment. In turn, this will increase patient access to this important imaging technique to ultimately advance the national health and quality of life. TECHNICAL ABSTRACT:Photoacoustic imaging provides deep tissue imaging similar to ultrasound but with enhanced optical contrast and additional functional and molecular imaging capabilities. However, no standardized performance test methods or phantoms exist for photoacoustic imaging system evaluation unlike mature techniques such as computed tomography. The fundamental limitation-and scientific problem to be studied here is a lack of materials to simultaneously simulate tissue properties over a broad range of optical wavelengths and acoustic frequencies. This leaves investigators, instrument manufacturers, and regulatory agencies without clear strategies to evaluate device safety and effectiveness. This project with the Food and Drug Administration (FDA) builds stable, biologically relevant imaging phantoms with well-characterized optical absorption/scattering coefficients, acoustic impedance, etc. that broadly simulate tissue over a wide range of optical wavelengths and acoustic frequencies. Objective 1 of this research develops phantoms with biologically relevant heterogeneous morphologies and light scattering artifacts during photoacoustic imaging. Phantom material optical and acoustic properties are rigorously characterized using spectrophotometry and acoustic pulse-transmission equipment available at FDA. The imaging phantoms contain multiple layers of background material with different optical and acoustic properties designed to mimic natural tissue (e.g. breast fat and glandular tissue or muscle and fat layers) as well as target inclusions. The inclusions have regular shapes (cylinders, spheres) of varying sizes as well as image-derived, tortuous vessel-mimicking structures. Objective 2 uses these phantoms to establish test methods that evaluate the impact of fluence artifacts on device performance in three different imaging systems. System image uniformity and out-of-plane sensitivity are evaluated during mechanical scanning of probes over realistic vessel-mimicking inclusions known to produce volumetric images. Sets of phantoms containing inclusions mimicking blood absorption at several oxygen saturation levels-but with different background optical properties and layer morphologies-serve in parametric studies of device performance in the face of spectral coloring artifacts. The measurement accuracy of our three photoacoustic imaging systems is quantified to determine device robustness using various fluence correction methods (diffusion theory, Monte Carlo simulations). The outcome is a well-validated tissue-mimicking phantom to support device developers and inform regulatory decision-making including use as a potential Food and Drug Administration Medical Device Development Tool.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.

非技术摘要：超声是图像疾病，包括癌症，骨科疾病和心脏功能的强大工具。超声波的一种局限性是，它的对比度低（对比是感兴趣区域和背景组织之间信号强度的差异）。因此，对一种特殊的超声（称为光声成像）进行了大量研究。光声成像仅在感兴趣领域才能产生声音 - 这增加了对比度。不幸的是，光声超声尚未被批准用于人们广泛使用。这可能部分是由于缺乏验证和标准化光声成像所需的新型成像设备的设备和方法。因此，这项工作将创建具有已知光学和声学特性的专门塑料对象，适合校准和标准化光声成像设备。该建议结合了学术界和食品药品监督管理局的专业知识，以识别具有类似于人类组织的光学和声学特性的材料。我们将创建对仪器制造商和医生有用的测试对象和方法。最终的测试对象将提高如何最好地创建光声成像仪器的知识，并可能简化该设备的监管批准。反过来，这将增加患者对这种重要成像技术的机会，以最终提高民族健康和生活质量。技术摘要：光声成像提供了类似于超声的深层组织成像，但具有增强的光学对比度以及其他功能和分子成像功能。但是，与成熟技术（例如计算机断层扫描）不同，没有用于光声成像系统评估的标准化性能测试方法或幻影。这里要研究的基本局限性和科学问题是缺乏在广泛的光波长和声学频率上同时模拟组织特性的材料。这使研究人员，仪器制造商和监管机构没有明确的策略来评估设备安全性和有效性。该项目与食品药品监督管理局（FDA）建立了具有良好特征的光吸收/散射系数，声学阻抗等稳定的，生物学相关的成像幻象，它们在多种光学波长和声学频率上广泛模拟组织。这项研究的目标1在光声成像过程中以生物学相关的异质形态和光散射伪影开发了幻象。幻影材料的光学和声学特性是使用分光光度法和FDA上可用的声学脉冲传输设备严格表征的。成像幻影包含多层背景材料，具有不同的光学和声学特性，旨在模仿天然组织（例如乳腺脂肪和腺组织或肌肉或肌肉和脂肪层）以及目标夹杂物。夹杂物具有不同大小的规则形状（圆柱体，球形）以及图像衍生的，曲折的容器模仿结构。目标2使用这些幻象来建立测试方法，以评估通知伪影对三种不同成像系统中设备性能的影响。在探针的机械扫描过程中，评估了系统的图像均匀性和平面敏感性，这些探针在模仿逼真的容器夹杂物上已知产生体积图像的探针。含有包含在几个氧饱和水平上的血液吸收水平的幻影集，但具有不同背景的光学特性和层形态 - 在频谱着色伪影的参数性研究中具有不同的背景光学特性和层形态。我们的三个光声成像系统的测量精度被量化以使用各种通力校正方法（扩散理论，蒙特卡洛模拟）来确定设备鲁棒性。结果是一种验证的模拟组织，以支持设备开发人员并为法规决策提供信息，包括用作潜在的食品和药物管理医疗设备开发工具。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛影响的审查标准来通过评估来支持的。

项目成果

3D-Bioprinted Phantom with Human Skin Phototypes for Biomedical Optics.

用于生物医学光学的具有人体皮肤光型的 3D 生物打印模型。

• DOI: 10.1002/adma.202206385
• 发表时间: 2023
• 期刊: Advanced materials (Deerfield Beach, Fla.)
• 作者: Yim,Wonjun;Zhou,Jiajing;Sasi,Lekshmi;Zhao,Jiayu;Yeung,Justin;Cheng,Yong;Jin,Zhicheng;Johnson,Wade;Xu,Ming;Palma-Chavez,Jorge;Fu,Lei;Qi,Baiyan;Retout,Maurice;Shah,NisargJ;Bae,Jinhye;Jokerst,JesseV
• 通讯作者: Jokerst,JesseV