Five-band microwave radiometer system for noninvasive brain temperature measurement in newborn babies: Phantom experiment and confidence interval
Five-band microwave radiometer system for noninvasive brain temperature measurement in newborn babies: Phantom experiment and confidence interval
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DOI：
10.1029/2011rs004736
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发表时间：
2011-11-19
期刊：
影响因子：
1.6
通讯作者：
Mizushina, S.
中科院分区：
文献类型：
--
作者：
Sugiura, T.;Hirata, H.;Mizushina, S.
新生儿低温脑治疗的临床试验目前受到难以测量脑深部温度的阻碍。作为一种可能的方法，无创和连续的温度监测，是完全被动的和固有的安全性是被动微波辐射（MWR）。我们已经开发了一个五波段微波辐射计系统与一个单一的双极化，矩形波导天线工作在1-4 GHz的范围内，并从五个辐射亮度温度的温度廓线检索的方法。本文讨论了（1）五个微波接收器的温度校准，（2）使用模拟新生儿温度分布的体模模型的测量实验，以及（3）无创监测脑深部温度的可行性。温度分辨率分别为0.103，0.129，0.138，0.105和0.111 K的1.2，1.65，2.3，3.0和3.6 GHz的接收器，分别。在距离体模表面5 cm深度处，温度估计的精度（2 sigma置信区间）约为0.7 ℃。精度，即使用该系统估计的温度与通过热电偶在5cm深度处测量的温度之间的差，约为2摄氏度。目前的结果对于临床应用来说并不令人满意，因为对于精度和5 cm深度的准确度，临床对准确度的要求必须优于1 ℃。由于这种不准确性的几个可能的原因已经确定，我们相信，该系统可以采取一个步骤更接近MWR的低温抢救治疗的临床应用。
Clinical trials of hypothermic brain treatment for newborn babies are currently hindered by the difficulty in measuring deep brain temperatures. As one of the possible methods for noninvasive and continuous temperature monitoring that is completely passive and inherently safe is passive microwave radiometry (MWR). We have developed a five-band microwave radiometer system with a single dual-polarized, rectangular waveguide antenna operating within the 1-4 GHz range and a method for retrieving the temperature profile from five radiometric brightness temperatures. This paper addresses (1) the temperature calibration for five microwave receivers, (2) the measurement experiment using a phantom model that mimics the temperature profile in a newborn baby, and (3) the feasibility for noninvasive monitoring of deep brain temperatures. Temperature resolutions were 0.103, 0.129, 0.138, 0.105 and 0.111 K for 1.2, 1.65, 2.3, 3.0 and 3.6 GHz receivers, respectively. The precision of temperature estimation (2 sigma confidence interval) was about 0.7 degrees C at a 5-cm depth from the phantom surface. Accuracy, which is the difference between the estimated temperature using this system and the measured temperature by a thermocouple at a depth of 5 cm, was about 2 degrees C. The current result is not satisfactory for clinical application because the clinical requirement for accuracy must be better than 1 degrees C for both precision and accuracy at a depth of 5 cm. Since a couple of possible causes for this inaccuracy have been identified, we believe that the system can take a step closer to the clinical application of MWR for hypothermic rescue treatment.