Non-Invasive Wideband Radiometer for Accurate Core Temperature Monitoring

项目摘要/摘要 临床研究表明，非常需要在整个围手术期过程中监测核心温度。 所需精度为&lt；0.5oC。准确、快速地检测超出预期范围的核心温度可以 减少不良反应的可能性，其结果可能是增加住院 患者死亡的成本(例如，在恶性高热期间)。不幸的是，目前测量岩心的方法 温度是侵入性和准确性之间的折衷，并表明有必要探索新的 解决办法。金标食道、鼻咽和肺动脉温度计是有创的，不 不适用于所有手术，也不适用于手术前后；皮肤表面温度计不能反映核心温度。 并受环境影响；零热流温度计不适合体温过高的场合。 变化，不适用于深度低温；最先进的辐射计不准确1oC到2oC 充其量，因此在临床上是不可接受的。这项研究的目标是探索一种 利用宽带测量创新的替代辐射测量技术，正演模拟 分层组织和干式仿生天线，实现非侵入性、准确和实时的核心温度 监控。假设低频和高频将从深部和深部推断温度 分别是近表面组织，其后处理将提供准确的岩心测量 温度(0.5摄氏度以内)，实时，在任何感兴趣的温度范围内，如在头上验证的- 模仿幽灵。这项研究意义重大，因为它揭示了以前不存在的关于 无创准确测温的宽带辐射计模型/算法及天线设计 监控。这个辐射计被设想为手术室的一个急需的补充，横跨 围手术期及以后的流程(如癌症诊断)。人们的期望是最终将该设备连接到 其他非侵入性监测仪(例如，心脏麻醉中的脑血氧仪)以开发新的 更可靠、更及时地检测并发症的标志物。在目标1中，宽带辐射测量模型和 天线将被开发出来。重点是翻译已经在 将层状冰盖的温度推断为层状头部介质的历史。这样的模式从来没有 被用于医学辐射测量的上下文中。然后将确定最佳频率范围，并 仿生天线将被设计来适应这种带宽，同时显示出前所未有的辐射 效率。在目标2中，我们的集成辐射计将在精确模拟的头部模型上进行验证 生物温度、流动和介电特性。仿生天线将被制造，连接到 辐射计，并用于验证：a)通过建模获得的亮度温度谱，以及b) 在反演核心温度时，假设精度为0.5oC。该宽带辐射计在我国的可行性研究 模拟组织的幻影将成为未来人体研究的基础。

PROJECT SUMMARY / ABSTRACT Clinical studies indicate a great need for monitoring core temperature throughout the perioperative process at a desired accuracy of <0.5oC. Accurate and fast detection of core temperatures beyond the intended ranges can decrease the likelihood of adverse effects, the outcomes of which may range from increased hospitalization costs to patient fatalities (e.g., during malignant hyperthermia). Unfortunately, current means of measuring core temperature present a tradeoff between invasiveness and accuracy and suggest a need for exploring novel solutions. Gold standard esophageal, nasopharynx and pulmonary artery thermometers are invasive and not feasible for all surgeries nor pre-/post-operatively; skin surface thermometers do not reflect core temperature and are affected by the environment; zero-heat-flux thermometers are unsuitable for intense body temperature changes and do not work for deep hypothermia; and state-of-the-art radiometers are inaccurate by 1oC to 2oC at best, and, hence, clinically unacceptable. The goal of this research is to explore the feasibility of an alternative radiometry technique that leverages innovations in broadband measurements, forward modeling of layered tissues, and dry biomimetic antennas to enable non-invasive, accurate, and real-time core temperature monitoring. The hypothesis is that low and high frequencies will infer the temperature from across deep and near-surface tissues, respectively, and that their post-processing will provide accurate measures of core temperature (within 0.5oC), in real-time, and across any temperature range of interest, as validated upon head- emulating phantoms. This study is significant because it reveals previously nonexistent knowledge on wideband radiometer models/algorithms and antenna designs for non-invasive and accurate core temperature monitoring. This radiometer is envisioned to be a much needed addition to the operating room, across the perioperative process, and beyond (e.g., cancer diagnostics). The expectation is to eventually link the device to other non-invasive monitors (e.g., cerebral oximeters in cardiac anesthesia) towards the development of new markers for more reliable and timely detection of complications. In Aim 1, wideband radiometry models and antennas will be developed. The focus entails translating models that have been successfully implemented in the past for inferring the temperature of layered ice sheets into layered head media. Such models have never been used in the context of medical radiometry. Optimal frequency ranges will then be identified, and biomimetic antennas will be designed to accommodate this bandwidth while exhibiting unprecedented radiation efficiency. In Aim 2, our integrated radiometer will be validated upon head phantoms that accurately emulate biological temperature flow and dielectric properties. Biomimetic antennas will be fabricated, connected to radiometers, and used to validate: a) the brightness temperature spectrum obtained from modeling, and b) the hypothesized accuracy of 0.5oC in retrieving the core temperature. Feasibility of this wideband radiometer in tissue-emulating phantoms will form the basis of future studies on human subjects.