Laser System for Clinical Photoacoustic Imaging Applications

用于临床光声成像应用的激光系统

• 批准号: 8524853
• 负责人: Donald F. Heller
• 金额: $ 15万
• 依托单位: LIGHT AGE, INC.
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-08-01 至 2014-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8524853
• 关键词: Acoustics; Adverse effects; Affect; Age; Animals; Area; Biological Assay; Biopsy; Blood Vessels; Breast; Characteristics; Clinic; Clinical; Clinical Research; Computer software; Consult; Detection; Development; Devices; Diagnosis; Diagnostic; Diagnostic Imaging; Diagnostic Neoplasm Staging; Diffuse; Discrimination; Early Diagnosis; Electronics; Ensure; Environment; Evaluation; Evaluation Studies; Exposure to; FDA approved; Feedback; Future; Goals; Hemoglobin; Hospitals; Human; Image; Imaging Device; Imaging technology; Ionizing radiation; Lasers; Lesion; Light; Mammary Neoplasms; Mammography; Medical Device; Methods; Patients; Penetration; Performance; Phase; Physiologic pulse; Physiological; Pigments; Plague; Property; Public Health; Pulse Rates; Research; Research Personnel; Resolution; Risk; Roentgen Rays; Screening for cancer; Sensitivity and Specificity; Signal Transduction; Source; Staging; Structure; Study Subject; System; Systems Integration; Technology; Testing; Time; Tissues; Tumor stage; Work; absorption; acoustic imaging; advanced system; alexandrite; base; commercial application; computerized data processing; cost; density; deoxyhemoglobin; design; detector; health care quality; human subject; improved; innovation; instrument; interest; medical specialties; meetings; millimeter; mortality; nanosecond; novel; operation; phase 1 study; photoacoustic imaging; programs; prototype; public health relevance; research clinical testing; screening; sensor; soft tissue; solid state; standard of care; systems research; tomography; tool; tumor; tumor specificity

DESCRIPTION (provided by applicant): Recent advances in photoacoustic tomography (PAT) have demonstrated its potential for 3D noninvasive high resolution imaging of soft tissues at penetration depths of many centimeters. Further, and perhaps even more importantly, imaging of tissue structure can be achieved while also providing crucial information regarding tissue composition and functionality. These results represent a dramatic breakthrough in soft tissue imaging technology. While there are a host of applications for this technology, breast imaging for the purpose of cancer screening and diagnosis is one of considerable import, affecting both cost and quality of healthcare nationally and globally.17 PAT makes use of intense, short-duration (nanosecond) laser pulses at specific wavelengths. The selective absorption of these wavelengths by targeted tissues gives rise to a primary acoustic signal. High resolution acoustic imaging is achieved by means of an advanced array of acoustic detectors and associated signal processing electronics and software. Tissue discrimination is obtained from differential images at multiple (deep red and near infrared) wavelengths. For breast imaging, requiring deep tissue penetration and tumor localization, the key wavelengths of interest lie within the tuning range of alexandrite lasers (or of alexandrite and Nd:YAG lasers (700 - 1100 nm). Consequently, the development of alexandrite lasers that meet the specific requirements for photoacoustic imaging of the breast is critical for the development of tumor diagnostic and imaging systems. These specific laser requirements relate primarily to the wavelengths used, pulse sequence in time, the pulse duration, the pulse energy, and the spatial uniformity of the beam produced by the laser system. Light Age Inc., is the inventor, designer, and principal developer of alexandrite and other solid-state laser systems. Over the past decade it has developed and delivered laser systems to researchers that meet certain key requirements for PAT These laser systems have been successfully developed for a variety of applications, including soft tissue imaging of the breast, and have recently provided some dramatic results (see Research Strategy section). The effort proposed here is to develop a prototype PAT system specifically for this application and to perform initial testing on animals and human subjects. Because the laser wavelengths are known to be non-mutagenic and the fluence levels used here are well-below those now routinely used to treat pigmented and vascular lesions in well-established and FDA-approved alexandrite laser-based medical devices, there is no conceivable risk to study subjects. The goal of this Phase I and follow-on Phase II program is to develop a laser-based PAT system suitable for use by a clinical imaging technician. The prototype clinical system will meet all of the basic requirements for breast imaging with respect to performance, system packaging, and ease of use. Additionally, it can provide advanced breast tumor discrimination capabilities beyond the present-day state-of-the-art. In the Phase I program, we will develop and demonstrate an improved laser source for PAT. Among other improvements in its performance properties it will provide a novel laser operating mode having rapid (pulse-to-pulse) wavelength switching. This may enable improvements in the tissue discrimination that can be achieved by means of differential imaging of vascular tissues due to oxy- and deoxy- hemoglobin concentrations. We will also conduct studies to determine how operating factors such as greater repetition rate and higher pulse energy will affect system size and cost. These studies will help guide the specifications for future clinical laser systems. In the Phase II program we will deliver a laser system that incorporates the rapid wavelength switching feature, to Optosonics, Inc. (a PAT system developer based in N. Carolina) for testing and clinical qualification. In Phase II we will also develop refinements to the laser and PAT control systems that are additionally desirable for clinical operation. To ensure that our technical work remains focused on the key areas of performance for PAT, throughout the Phase I program we will consult with collaborators at Optosonics.

描述（由申请人提供）：光声断层扫描（PAT）的最新进展已经证明了其在穿透深度为许多厘米的软组织的3D无创高分辨率成像的潜力。此外，可能甚至更重要的是，可以实现组织结构的成像，同时还提供关于组织组成和功能的关键信息。这些结果代表了软组织成像技术的重大突破。虽然这项技术有许多应用，但用于癌症筛查和诊断的乳腺成像是相当重要的一项，影响着国家和全球医疗保健的成本和质量。目标组织对这些波长的选择性吸收产生初级声学信号。高分辨率声学成像是通过先进的声学探测器阵列和相关的信号处理电子设备和软件来实现的。从多个（深红色和近红外）波长处的差分图像获得组织辨别。对于需要深层组织穿透和肿瘤定位的乳腺成像，感兴趣的关键波长位于翠绿宝石激光器（或翠绿宝石和Nd：YAG激光器（700 - 1100 nm））的调谐范围内。因此，开发满足乳腺光声成像特定要求的翠绿宝石激光器对于肿瘤诊断和成像系统的开发至关重要。这些具体的激光要求主要涉及所使用的波长、脉冲时间序列、脉冲持续时间、脉冲能量和激光系统产生的光束的空间均匀性。 Light Age Inc.是紫翠宝石和其他固态激光系统的发明者、设计者和主要开发者。在过去的十年中，它已经开发和交付激光系统，以满足某些关键要求的研究人员PAT这些激光系统已成功地开发了各种应用，包括软组织成像的乳房，并在最近提供了一些戏剧性的结果（见研究策略部分）。这里提出的努力是开发一个原型PAT系统专门用于此应用程序，并进行初步测试的动物和人类受试者。由于已知激光波长无致突变性，且此处使用的通量水平远低于目前在成熟且FDA批准的基于翠绿宝石激光的医疗器械中常规用于治疗色素和血管病变的通量水平，因此对研究受试者没有可想象的风险。本阶段I和后续阶段II计划的目标是开发适合临床成像技术人员使用的基于激光的PAT系统。原型临床系统将满足乳腺成像在性能、系统包装和易用性方面的所有基本要求。此外，它可以提供先进的乳腺肿瘤识别能力超越了目前的国家的最先进的。在第一阶段的计划，我们将开发和展示一个改进的激光源的PAT。除了其性能特性的其他改进之外，它还将提供一种具有快速（脉冲到脉冲）波长切换的新型激光操作模式。这可以使得能够改进组织辨别，这可以借助于由于氧合血红蛋白和脱氧血红蛋白浓度而对血管组织进行的差分成像来实现。我们亦会进行研究，以确定操作因素，例如较高的重复频率和较高的脉冲能量，会如何影响系统的大小和成本。这些研究将有助于指导未来临床激光系统的规范。在第二阶段计划中，我们将向Optosonics，Inc.提供一个具有快速波长切换功能的激光系统。（一个PAT系统开发人员在N。卡罗莱纳）进行测试和临床鉴定。在第二阶段，我们还将对激光和PAT控制系统进行改进，以满足临床手术的需要。为了确保我们的技术工作仍然集中在PAT的关键性能领域，在整个第一阶段计划中，我们将与Optosonics的合作者进行磋商。