Development of EPR and NIR Oximetry for Diabetic Foot

描述（由申请人提供）：糖尿病显著增加了微血管和大血管疾病的风险，这是这种日益流行的疾病中发病率和死亡率较高的主要原因。由于循环受损导致的组织氧合不良导致糖尿病患者足部溃疡愈合不良、感染和恶化;这是基本的潜在病理生理因素。在目前的临床实践中，没有直接测定组织氧含量的技术。相反，临床医生需要依靠各种方法来测量灌注，如多普勒超声，或间接测量组织氧合，经皮氧测量（TcO 2）。后者检测氧气扩散通过皮肤温暖到42-44？C，这与组织中的实际pO 2有复杂的关系。该项目将应用两种新兴技术：电子顺磁共振（EPR）血氧饱和度测定和近红外光谱（NIR），以更直接、更可靠地测量健康志愿者的组织氧合。最终目的是将该技术扩展到糖尿病患者，用于疾病的临床管理。EPR是一种新的血氧测定模式，可直接测量组织氧含量，NIR血氧测定可表征血管内血红蛋白的量和饱和度，因此这两种技术的组合将提供有关氧输送和局部浓度的补充信息，从而提供更完整的组织氧合情况。EPR和NIR的主要潜在优势在于它们提供了以前无法获得的信息，即直接组织氧含量，并且可以在长时间内无创地获得有意义的重复测量。该信息对于表征疾病的状态、确定治疗干预对组织氧合的影响以及氧合与疾病进展之间的关系将是非常有用的。已经获得了有希望的初步结果，表明多年来跟踪人体组织氧的可行性。如果这些技术的承诺得到实现，临床医生将有一个新的强大的工具，管理外周血管疾病的基础上，病理生理学。

DESCRIPTION (provided by applicant): Diabetes markedly raises the risk of microvascular and macrovascular diseases, major contributors to higher morbidity and mortality in this increasingly prevalent disorder. The resulting poor tissue oxygenation due to compromised circulation accounts for the poor healing, infection, and deterioration of foot ulcers in diabetics; this is the basic underlying pathophysiological factor. In current clinical practice, there is no technique available for direct determination of tissue oxygen content. Instead, clinicians need to rely on various methods that attempt to measure perfusion such as Doppler ultrasound, or an indirect measure of tissue oxygenation, transcutaneous oxygen measurement (TcO2). The latter detects oxygen diffusing through skin warmed to 42-44? C by the instrument, which has a complex relationship to the actual pO2 in the tissue. This project will apply 2 emerging techniques; electron paramagnetic resonance (EPR) oximetry and near infrared spectroscopy (NIR) to measure tissue oxygenation more directly and reliably in healthy volunteers. The ultimate aim is to extend the techniques to diabetic patients for clinical management of the disease. EPR is a new oximetry modality that directly measures tissue oxygen content and NIR oximetry characterizes the amount and saturation of intravascular hemoglobin, so a combination of these 2 techniques will provide complementary information about oxygen delivery and local concentration, providing a more complete picture of the tissue oxygenation. The major potential advantages of EPR and NIR are that they provide information not previously available, namely direct tissue oxygen content, and that meaningful repeated measurements can be obtained non-invasively over a long period of time. This information would be extremely useful for characterizing the status of the disease, and to determine the effects of therapeutic intervention on tissue oxygenation, and the relationship between oxygenation and progression of the disease. Promising preliminary results have been obtained, indicating the feasibility of following tissue oxygen in humans for years. If the promise of these techniques is fulfilled, clinicians will have a new powerful tool for management of peripheral vascular disease, based on fundamental pathophysiology.