Abstract:
Temperature is a hallmark parameter influencing almost all magnetic resonance properties (e.g., T1 , T2 , proton density, and diffusion). In the preclinical setting, temperature has a large influence on animal physiology (e.g., respiration rate, heart rate, metabolism, and oxidative stress) and needs to be carefully regulated, especially when the animal is under anesthesia and thermoregulation is disrupted. We present an open-source heating and cooling system capable of regulating the temperature of the animal. The system was designed using Peltier modules capable of heating or cooling a circulating water bath with active temperature feedback. Feedback was obtained using a commercial thermistor, placed in the animal rectum, and a proportional-integral-derivative controller was used to modulate the temperature. Its operation was demonstrated in a phantom as well as in mouse and rat animal models, where the standard deviation of the temperature of the animal upon convergence was less than a 10th of a degree. An application where brain temperature of a mouse was modulated was demonstrated using an invasive optical probe and noninvasive magnetic resonance spectroscopic thermometry measurements.
摘要:
温度是影响几乎所有磁共振特性的标志参数(例如,T1,T2,质子密度,和扩散)。在临床前环境中,温度对动物生理学有很大影响(例如,呼吸频率,心率,新陈代谢,和氧化应激),并且需要仔细调节,特别是当动物处于麻醉状态并且体温调节中断时。我们提出了一种能够调节动物温度的开源加热和冷却系统。该系统是使用能够加热或冷却具有主动温度反馈的循环水浴的珀尔帖模块设计的。反馈是使用商用热敏电阻获得的,放在动物直肠里,并使用比例-积分-微分控制器来调节温度。它的操作在体模以及小鼠和大鼠动物模型中得到了证明,其中收敛时动物温度的标准偏差小于十分之一度。使用侵入性光学探针和非侵入性磁共振波谱测温测量来证明调节小鼠大脑温度的应用。