超顺磁性氧化铁对肝脏MR成像效果的影响  

Superparamagnetic iron oxide nanoparticles as contrast agent for liver MR imaging

作　　者：张勤慧[1] 姜启玉[2,3] 顾海鹰[2,3] 

机构地区：[1]南通大学附属医院影像科,江苏南通226001 [2]南通大学公共卫生学院 [3]南通大学生命分析化学研究所,江苏南通226007

出　　处：《中国医学影像技术》2010年第10期1809-1813,共5页Chinese Journal of Medical Imaging Technology

基　　金：国家自然科学基金(20875051、20675042);江苏省自然科学基金(BK2009152);南通大学自然科学项目(07Z109)

摘　　要：目的观察超顺磁性氧化铁(SPIO)对肝脏MR成像效果的影响。方法用化学共沉淀法制备具有肝脏特异性的MR对比剂SPIO,分别将生理盐水、SPIO样品及目前临床广泛使用的Gd-DTPA注入30只大白兔体内,5min、30min、60min后进行MR成像,分别测量肝脏和背部肌肉的信号强度并计算相对信号强度比(相对信号强度比=肝脏信号强度/肌肉信号强度)。结果 Gd-DTPA使肝脏T1WI相对信号强度比(ENH)显著升高,但30min即开始恢复,持续时间短,SPIO使肝脏T2WI相对信号强度比显著降低,60min仍能维持高ENH,持续时间长。结论 SPIO具有良好的晶体结构和均匀的纳米尺寸,能显著降低肝脏MRT2WI相对信号强度比,可作为MRI阴性对比剂。Objective To investigate the influence of superparamagnetic iron oxide （SPIO） nanoparticles as contrast agent on liver MR imaging. Methods A novel hepatic-specific MR contrast agent—superparamagnetic iron oxide （SPIO） was synthesized with coprecipitation. Thirty rabbits were randomly divided into three equal groups with the injection of the SPIO colloid,Gd-DTPA and physiologic saline as contrast agents individually. MR imaging was performed at 5 min,30 min and 60 min following the injection of the above three agents,and the signal intensities of liver and back muscle before and after enhancement were measured and calculated using formulation：ENH=signal intensity of hepar/signal intensity of muscle. Results ENH increased significantly in T1WI in Gd-DTPA group,but started to restore in 30 min. The duration was short. ENH decreased significantly in T2WI in SPIO group,and maintained high level for more than 60 min. Conclusion With good crystal structure and adqulis dimension,SPIO can decrease the relative signal intensity of liver significantly in T2WI,and therefore can be used as negative MR contrast agent.

关 键 词：超顺磁性氧化铁 磁共振成像 肝脏 

分 类 号：R-332[医药卫生] R445.2