A handheld scanner for clinical oximetry

描述(由申请人提供)：通过皮肤的经皮氧气灌注量的测量在临床上被用来测量流向身体某一区域的血流量，并作为伤口愈合潜力的指示性测量。局部血氧仪也可用于追踪外周血管疾病(PVD)。目前，临床上唯一用于这一目的的技术是使用基于电极的传感器的经皮氧气监测(TCOM)，这需要一个活跃的加热元件来鼓励氧气通过皮肤扩散。皮下(皮肤表面下2-3 mm)组织氧测量将有助于确定用于重建手术的带血管的游离组织瓣或慢性创面周围组织的血流量。 我们的团队已经证明，用于电子顺磁共振(EPR)血氧仪的生物聚合物包裹的探针可以在局部应用于感兴趣区域或植入皮肤下时用于此类应用。由于现有器械的大小、重量和空间限制，目前在临床环境中使用EPR进行此类测量是不可行的。因此，我们建议设计、构建和测试一种新的便携式EPR系统，用于临床血氧仪应用。 设想中的设备将类似于临床超声设备，带有一个“棒”组件，它将与皮肤接触，从放置在身体上或植入表面以下的探头传感器获得血氧测量结果。我们将使用计算机建模来确定磁体和谐振器的最佳布置，然后再构建工作原型设备。然后，我们将测试和表征将要使用的氧气敏感探针。然后，我们将使用原型设备来量化大鼠慢性创伤模型中的组织氧合，并继续使用便携式EPR设备在人类志愿者身上进行验证测量，以将这项新技术与现有的基于电极的TCOM进行比较。

DESCRIPTION (provided by applicant): Measurement of transcutaneous oxygen perfusion through the skin is used clinically as a measure of blood flow to a region of the body, and serves as an indicative measure of wound healing potential. Topical oximetry may also be useful for tracking peripheral vascular disease (PVD). Currently, the only clinically-applied technique used for this purpose is transcutaneous oxygen monitoring (TCOM) using electrode based sensors, which require an active heating element to encourage diffusion of oxygen through the skin. Subcutaneous (2 - 3 mm below the skin surface) tissue oxygen measurements would be useful in determining blood flow in vascularized free tissue flaps used for reconstructive surgery or in tissues surrounding chronic wounds. Our group has demonstrated that biopolymer-encapsulated probes used in electron paramagnetic resonance (EPR) oximetry can be used for such applications when applied topically to the region of interest, or implanted below the skin. The use of EPR for such measurements is currently not feasible in a clinical setting due to the size, weight, and space restrictions presented by existing instrumentation. We therefore propose to design, build, and test a new, portable EPR system for clinical oximetry applications. The envisioned device will be similar to a clinical ultrasound unit, with a "wand" assembly that will be placed in contact with the skin to obtain oximetry measurements from the probe sensors placed on the body, or implanted just below the surface. We will use computer modeling to determine the optimum arrangement of magnets and resonator prior to construction of a working prototype device. We will then test and characterize the oxygen-sensitive probes to be used. We will then use the prototype device to quantify tissue oxygenation in a rat chronic wound model, and continue with validation measurements using the portable EPR unit on human volunteers to compare this new technology with the existing electrode-based TCOM.