Non-invasive measurement of brain temperature with microwave radiometry: demonstration in a head phantom and clinical case.
Non-invasive measurement of brain temperature with microwave radiometry: demonstration in a head phantom and clinical case.
复制标题
DOI：
10.15274/nrj-2014-10001
复制
发表时间：
2014-02
期刊：
影响因子：
--
通讯作者：
Maccarini PF
中科院分区：
文献类型：
--
作者：
Stauffer PR;Snow BW;Rodrigues DB;Salahi S;Oliveira TR;Reudink D;Maccarini PF
这项研究表征了非侵入性微波辐射温度计的灵敏度和准确性，该温度计旨在直接监测大脑中的身体核心温度，以帮助从手术过程中发生的体温过低中快速恢复。人体头部模型是由独立的大脑和头皮区域构建的，该区域由在完整头骨两侧以独立温度循环的组织等效液体组成。该测试设置提供了不同的表面/深层组织温度，用于量化大脑温度变化的敏感性，与头皮和周围环境无关。在多层人体头部模型中校准 500MHz 带宽微波辐射计后，在 2 小时手术期间监测的儿科患者中评估了临床监测的可行性。当大脑模型降低 10°C 并恢复到原始温度 (37°C) 时，计算出的辐射等效脑温度与测量温度的误差在 0.4°C 以内，而头皮在 4.6 小时的实验中保持恒定。在一次 2 小时的儿科手术中，辐射测量的脑部温度与直肠和鼻咽部的温度相差 1-2°C，但在快速冷却和加热期间，脑部温度与其他核心温度替代值偏差 2-4°C。在具有不同头皮和大脑温度的多层人体头部模型中对单波段辐射计进行了校准和测试。该系统的预期临床用途通过监测儿科患者手术期间的脑部温度得到证明。该辐射计表现出长期稳定性、准确性和灵敏度，足以在手术期间对深部脑温度进行临床监测。
This study characterizes the sensitivity and accuracy of a non-invasive microwave radiometric thermometer intended for monitoring body core temperature directly in brain to assist rapid recovery from hypothermia such as occurs during surgical procedures. A human head model was constructed with separate brain and scalp regions consisting of tissue equivalent liquids circulating at independent temperatures on either side of an intact skull. This test setup provided differential surface/deep tissue temperatures for quantifying sensitivity to change in brain temperature independent of scalp and surrounding environment. Following calibration of a 500MHz bandwidth microwave radiometer in the multilayer human head model, the feasibility of clinical monitoring was assessed in a pediatric patient monitored during a 2-hour surgery. The calculated radiometric equivalent brain temperature agreed within 0.4°C of measured temperature when the brain phantom was lowered 10°C and returned to original temperature (37°C), while scalp was maintained constant over a 4.6-hour experiment. During a 2-hour pediatric surgery, the radiometrically measured brain temperature tracked within 1–2°C of rectal and nasopharynx temperatures, except during rapid cooldown and heatup periods when brain temperature deviated 2–4°C from other core temperature surrogates. A single band radiometer was calibrated and tested in a multilayer model of the human head with differential scalp and brain temperature. The intended clinical use of this system was demonstrated by monitoring brain temperature during surgery of a pediatric patient. The radiometer demonstrated long term stability, accuracy and sensitivity sufficient for clinical monitoring of deep brain temperature during surgery.