There is a strong need to enable accurate and convenient oxygen measurements in vivo for human subjects to improve treatments for cancer, peripheral vascular disease, and other diseases where tissue oxygen levels have a significant impact. While EPR spectroscopy has the potential to do this effectively, the full exploitation of these capabilities requires optimization of resonators for use with human subjects. Patient motion, and its effects on resonator coupling and positioning relative to the implanted oximetry probe, is a major source of noise and artifacts. Additionally, optimization of detection sensitivity to enable measurements from tissues at depths of several centimeters with clinically practical acquisition times is needed. To meet these needs, surface resonators with high sensitivity and flexible cables that allow the detection loop to be conveniently attached to the skin surface were developed for use with low frequency (L-Band, 1.15 GHz) continuous wave EPR. These resonators include a multi-segment sensing loop with a common capacitance. The light-weight segmented sensing loops, with diameters of 10–20 mm, can be connected to a commercial topical fixation applicator to conveniently and securely position them on patients’ skin surfaces. It was shown that a resonator of 20 mm in diameter makes it possible to obtain adequate EPR signals in tissue phantoms up to a depth of 20 mm with ~ 2 min of signal averaging. This novel lightweight resonator design, with sensitive multi-segment design and flexible cable with skin surface attachment, significantly reduced the impacts of subject motion enabling reliable EPR oximetry measurements in human subjects.

迫切需要为人类受试者提供准确和方便的体内氧测量，以改进对癌症、外周血管疾病和其他组织氧水平具有显着影响的疾病的治疗。虽然 EPR 光谱有可能有效地做到这一点，但充分利用这些功能需要优化谐振器以供人类受试者使用。患者运动及其对谐振器耦合和相对于植入式血氧饱和度探头定位的影响是噪声和伪影的主要来源。此外，还需要优化检测灵敏度，以便能够以临床实际采集时间从几厘米深度的组织中进行测量。为了满足这些需求，开发了具有高灵敏度和柔性电缆的表面谐振器，可以方便地将检测回路连接到皮肤表面，用于低频（L 波段，1.15 GHz）连续波 EPR。这些谐振器包括一个带有公共电容的多段感应回路。直径为 10-20 毫米的轻型分段传感环可以连接到商用局部固定涂药器，以方便、安全地将它们定位在患者的皮肤表面。结果表明，直径为 20 毫米的谐振器可以在深度为 20 毫米的组织体模中获得足够的 EPR 信号，平均信号时间为 2 分钟。这种新颖的轻型谐振器设计，具有灵敏的多段设计和带有皮肤表面连接的柔性电缆，