棕色脂肪组织是一种以消耗能量为主要功能的特殊脂肪组织，是治疗肥胖和相关代谢疾病的新靶点。棕色脂肪的活性是衡量其耗能产热能力的关键指标，当前其评估主要是活检等有创的生物学方法，因此，发展无创在体棕色脂肪活性评估方法对于深入探究棕色脂肪与相关疾病的关系具有重要科学价值。棕色脂肪激活时的温度变化是其活性的最直观表现，因此，温度测量被认为是在体活性评估的最有效方法，但是，目前尚缺乏精准在体测温方法。本项目在前期离体组织研究基础之上，提出在体棕色脂肪磁共振温度成像方法，针对测温精度低的挑战，围绕物理参数、成像参数及估算模型对测温精度的影响机制这一关键科学问题，利用理论计算和模拟仿真研究影响测温精度的参数，确立最优参数并建立在体温度成像算法；基于在体激活实验，以生物学方法为对照，研究棕色脂肪活性与温度变化的定量关系，建立在体评估方法。本项目研究将为促进棕色脂肪活性与肥胖及相关疾病关系的研究提供新方法。

Brown adipose tissue (BAT) is a specific tissue whose main function is consuming energy. Therefore BAT is considered as the new therapeutic target for obesity and the related metabolic diseases. The most key indicator for evaluating the ability of consuming energy and generating heat is BAT activity. The current main method for activity evaluation is invasive biological method, such as biopsy. Therefore, the development of method for evaluating BAT activity in vivo is of scientific significance for in-depth studying of the relationship between BAT and obesity and the related diseases. The temperature change of BAT after activated is the most direct appearance of BAT activity. As a result, thermometry in BAT is considered to be the best method to evaluate BAT activity. However, there is no such a method to measure the temperature of BAT precisely at present. On the strength of my previous study in ex-vivo BAT, the current project aims to establish an in-vivo magnetic resonance thermometric method for BAT. To solve the challenge of low precision in BAT thermometry, the project will solve the following scientific issue: the relationship of the BAT’s physical parameters, signal acquisition parameters and signal models with the precision of measured temperatures. The project will adopt theoretical calculation and analog simulation methods to explore and find the optimal parameters who are related to the noise performance of measured temperatures, and then establish the in-vivo magnetic resonance thermometric method. Finally, the quantitative relation between BAT activity by biological method and the temperature profiles established by thermometric method are evaluated using in vivo experiments. The established thermometric method based on magnetic resonance imaging in this project is thought to provide a new method to promote the in-depth study of the relationship between BAT and obesity and other related diseases.