肾脏3.0T磁共振扩散成像的研究

【作者】 朱捷；

【导师】 周翔平； 刘荣波； 陈卫霞；

【作者基本信息】 四川大学 ， 影像医学与核医学， 2006， 博士

【摘要】 背景及目的 磁共振扩散成像(MR Diffusion Imaging)通过分析水分子随机运动的动态分布状况，能够无创而可靠的提供活体组织病理生理状态下组织成分之间水交换的功能状态，包括扩散加权成像(Diffusion-weighted Imaging，DWI)和扩散张量成像(Diffusion Tensor Imaging DTI)。平面回波成像(Echo-Planar Imaging，EPI)技术的应用，拓展了磁共振扩散成像在腹部的应用，肾脏由于高血流量及强大的水转运量成为扩散研究价值较大的脏器。3.0T磁共振信噪比提高及扫描时间缩短，能获得高分辨率的图像，同1.5T磁共振相比，在扩散成像上有显著的优越性。本研究通过正常肾脏扩散成像的描述性研究，探讨肾脏3.0T磁共振扩散成像适合的的扫描参数及测量方法，以及性别和年龄等因素对正常值的影响。 材料和方法 研究对象包括48例健康志愿者。肾脏常规MR扫描后行DWI及DTI扫描，采用SS-EPI-DWI(DTI)序列，并行空间采集成像和空间预饱和技术，单次屏气。DWI的方向取前／后，右／左，上／下三方向的拟和b值取100、500和800s／mm~2；DTI为6个方向，b值取800s／mm~2，工作站自动合成ADC图及DTI图，手工测量相应ADC值及FA、RA值。利于扩散加权纤维成像(Diffusion Tensor Tractography，DTT)技术绘制更多还原

【Abstract】 Part I3.0T MR Diffusion Imaging of Normal KidneyBackground and purpose: MR diffusion imaging, including diffusion -weighted imaging (DWI) and diffusion tensor imaging (DTI), could provide the information of water commutation in tissue under physiological and pathological condition. Echo-planner imaging technique has broadened the application of MR diffusion imaging in abdomen. Kidney is a valuable organ for diffusion imaging research as its high volume of blood flow and water commutation. Compared with 1.5T MR, 3.0T MR has higher resolution of imaging with better SNR and shorter scanning time. Our aim was to study the normal appearance of kidney in MR diffusion imaging and to probe the suitable scanning parameters and measurement methods. The infection of sex and age is also discussed.Material and methods: Forty-eight volunteers underwent diffusion-sensitive magnetic resonance (MR) imaging of the kidneys with a breathe-hold single-shot echo planar imaging (SS-EPI) sequence. DWI was the trace imaging of three orthogonal directions with b values of 100, 500 and 800s/mm~2, and DTI was in 6 direction with b values of 100 and 800s/mm~2. ADCs, FA and RA values were measured from ADC map and DTI map.更多还原