Hand-held advanced functional imager for assessing local tissue oxygenation

 描述(由申请人提供)：我们建议开发一种先进的功能成像仪来评估红细胞(RBC)输注。在这个SBIR第一阶段项目中，原型将在一个功能模型中进行测试。该成像仪的关键功能是能够用手持探头量化局部组织的氧合，以便轻松接触组织。我们的初步市场调查表明，这种仪器的需求很大，以帮助医生有效地进行RBC输血，这是住院期间最常见的操作程序。我们假设，非侵入性技术能够提供直径在20-50微米之间的组织微血管的重复三维功能图，其中氧气开始扩散到实质组织，将显著降低红细胞输注的发病率和死亡率。这种技术有可能通过提供关于最佳输血阈值的有利信息，以及随着储存时间和条件对红细胞降解的评估来指导程序。目前用于评估RBC输血的成像技术包括：侧流暗场(SDF)、正交偏振光谱(OPS)和近红外光谱(NIRS)，它们不能提供直径20-50微米的单个微血管中微血管血氧和流动的三维图像，SDF和OPS提供的是二维非深度分辨的血管造影和血流微血管信息，因此无法提供氧合信息和小动脉和小静脉的区分。NIRS提供了几个平方毫米区域的平均动脉氧合信息，因此错过了氧气提取、血流和空间分辨率。我们建议通过将多功能光学相干断层扫描(OCT)和OPS结合在单个手持设备中来填补这一空白。OPS提供实时2-D微血管图以供用户指导，而多功能OCT提供3-D微血管造影和单个小动脉和小静脉的血流量和血红蛋白氧饱和度(SO2)地图，以及O2提取和相对氧气消耗。我们相信，我们的方法提供了解决关键问题所需的性能，并为成功商业化提供了一条清晰的道路。该项目将通过提供关键的临床信息来改善患者的预后，从而产生强大的社会影响。局部组织氧输送和消耗的定量成像不仅可以改善红细胞输注的结果，而且在降低许多破坏性疾病的发病率和死亡率方面具有很大的潜力，这些疾病包括各种恶性、炎症性、缺血性、感染性和免疫性疾病。

 DESCRIPTION (provided by applicant): We propose development of an advanced functional imager to assess red blood cell (RBC) transfusion. The prototype will be tested in a functional phantom during this SBIR Phase I project. The key features of the imager are the ability to quantify local tissue oxygenation with a handheld probe for easy tissue access. Our preliminarily market research indicates a strong demand for such instrument to help physicians effectively perform RBC transfusion, which is the most common inpatient hospital procedure. We hypothesize that non-invasive technology capable of providing repeated 3-D functional maps of tissue microvessels with diameters between 20-50 µm, where oxygen starts diffusing to the parenchymal tissues, will significantly decrease morbidity and mortality in RBC transfusion. Such technology has the potential to guide procedures by providing favorable information about optimal transfusion threshold, as well as evaluation of RBCs degradation with storage time and conditions. Current imaging technologies used to assess RBC transfusion include: Sidestream Dark Field (SDF), Orthogonal Polarization Spectral (OPS) and Near Infrared Spectroscopy (NIRS) do not provide 3-D maps of microvascular blood oxygenation and flow in a single microvessel with diameter 20-50 µm. SDF and OPS provide 2-D non-depth-resolved angiography and blood flow microvasculature information, thus missing the oxygenation information and arterioles and venules discrimination. The NIRS provides average arterial oxygenation information from a few square mm area and thus misses oxygen extraction, blood flow and spatial resolution. We propose to fill this gap with the proposed imaging technology for RBC transfusion assessment by combining multifunctional optical coherence tomography (OCT) and OPS in a single hand- held device. OPS offers real-time 2-D microvasculature map for user guidance purposes while multifunctional OCT provides 3-D microvasculature angiography and maps of blood flow and hemoglobin oxygen (O2) saturation (SO2) in single arterioles and venules as well as O2 extraction and relative oxygen consumption. We believe our approach provides the needed performance to solve a critical problem and a clear path to successful commercialization. This project will have strong social impact by providing critical clinical information to improve patient outcomes. Quantitative imaging of local tissue oxygen delivery and consumption will not only improve RBC transfusion outcome but has a great potential to decrease morbidity and mortality in many devastating diseases with vascular etiology including a variety of malignant, inflammatory, ischemic, infectious and immune disorders.