Optoacoustic monitoring of cerebral blood oxygenation

脑血氧饱和度的光声监测

• 批准号: 6752421
• 负责人: RINAT O. ESENALIEV
• 金额: $ 32.28万
• 依托单位: UNIVERSITY OF TEXAS MED BR GALVESTON
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-06-01 至 2006-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6752421
• 关键词: biological signal transduction; blood; brain; clinical research; human middle age (35-64); human subject; human tissue; oximetry; oxygen transport; oxyhemoglobin; postmortem; respiratory gas; respiratory oxygen; respiratory oxygenation; technology /technique development; young adult human (21-34)

DESCRIPTION (provided by applicant): Management of acute, life-threatening neurologic illnesses, such as severe traumatic brain injury, is facilitated by accurate and continuous monitoring of cerebral oxygenation. However, current monitoring systems are invasive, requiring either cannulation of the internal jugular venous bulb or insertion of a probe directly into the brain. Nearinfrared spectroscopy, a noninvasive method of monitoring cerebral blood oxygenation, is promising, but has yet to be satisfactorily calibrated to provide quantitative measurement in adults. At present there is no system for accurate, noninvasive, and continuous monitoring of cerebral blood oxygenation. We proposed and performed in vitro and in vivo testing of a novel optoacoustic technique that accurately and continuously measures blood oxygenation directly from the superior sagittal sinus, a structure that can easily be localized due to the high resolution of the optoacoustic technique. The optoacoustic technique is based on generation of ultrasonic (optoacoustic) waves by laser pulses and detection of these waves by a sensitive acoustic transducer. Optoacoustic monitoring of blood oxygenation utilizes well-established differences in the optical absorption coefficients of oxy- and deoxyhemoglobin in the nearinfrared spectral range. During our current NIH R21 project supported by an NINDS grant under the Program Announcement PA-98-050 (directed at the development of innovative technologies including photoacoustic brain monitoring), we designed, built, and tested a noninvasive optoacoustic system for accurate monitoring of cerebral blood oxygenation. Our in vitro and in vivo (in sheep) studies demonstrated that: (1) the parameters of the optoacoustic waves are linearly dependent on blood oxygenation; (2) the use of specially designed transducers and optoacoustic probes allows sensitive detection despite optical and acoustic attenuation by thick bone; and (3) this technique can measure blood oxygenation with high accuracy. In this grant application, we propose to further develop this technique under this program announcement. The specific aims of the project are: (1) to modify the optoacoustic system to provide multiwavelength measurements and perform evaluation of the system in cadavers; (2) to evaluate it in vivo in volunteers; and (3) to evaluate the system performance in patients with traumatic brain injury. By the end of the project the system will be developed sufficiently to permit multi-center clinical trials.

描述（由申请人提供）： 准确、持续的脑氧合监测有助于治疗急性、危及生命的神经系统疾病，例如严重的创伤性脑损伤。然而，当前的监测系统是侵入性的，需要对颈内静脉球进行插管或将探针直接插入大脑。近红外光谱是一种监测脑血氧合的无创方法，前景广阔，但尚未得到令人满意的校准，无法为成人提供定量测量。目前尚无准确、无创、连续监测脑血氧饱和度的系统。我们提出并进行了一种新型光声技术的体外和体内测试，该技术可以直接从上矢状窦准确连续地测量血氧，由于光声技术的高分辨率，上矢状窦是一种可以轻松定位的结构。光声技术基于激光脉冲产生超声波（光声）并通过灵敏的声换能器检测这些波。血氧的光声监测利用近红外光谱范围内氧合血红蛋白和脱氧血红蛋白的光吸收系数的既定差异。在我们当前的 NIH R21 项目中，我们根据计划公告 PA-98-050（旨在开发包括光声脑监测在内的创新技术）提供 NINDS 拨款支持，期间，我们设计、构建和测试了一种无创光声系统，用于精确监测脑血氧饱和度。我们的体外和体内（绵羊）研究表明：（1）光声波的参数与血液氧合呈线性相关； (2)使用专门设计的换能器和光声探头，尽管厚骨会造成光学和声学衰减，但仍可以进行灵敏的检测； (3)该技术可以高精度地测量血氧。在本次拨款申请中，我们建议根据本计划公告进一步开发这项技术。该项目的具体目标是：（1）修改光声系统以提供多波长测量并在尸体中对该系统进行评估； (2) 在志愿者体内进行评价； (3) 评估脑外伤患者的系统性能。到项目结束时，该系统将得到充分开发，可以进行多中心临床试验。