提高3DTOF-MRA图像质量的研究  

Research on 3D of Quality Improvement TOF-MRA Images

作　　者：肖建明[1] 陈志凡[1] 陈云涛[1] 彭涛[1] 

机构地区：[1]成都大学附属医院放射科,四川成都610081

出　　处：《中国医疗设备》2013年第10期158-161,共4页China Medical Devices

摘　　要：目的探讨组合应用重叠多个簿层块采集(MOTSA)、倾斜优化非饱和激励(TONE)及磁化传递(MT)对时间飞跃法磁共振血管成像(TOF-MRA)图像质量及扫描时间的影响。方法回顾分析50例健康志愿者TOF-MRA扫描资料,同时采用不同参数组合的6个序列所得原始图像及最大密度投影(MIP)重建图像,6个序列分别是:TOF-MOTSA28(20%)-TONEMT、TOF-MOTSA28(28.57%)-TONE-MT、TOF-MOTSA40(20%)-TONE-MT、TOFMOTSA56(20%)-TONE-MT、TOF-MOTSA40(20%)-MT、TOF-MOTSA40(20%)-TONE(MOTSA28、MOTSA40、MOTSA56分别表示单个薄层块内的层数为28、40、56,20%或28.57%表示块重叠比例)。对比各序列MIP重建图像完整度、均匀度、相邻块之间血管移行平滑度及扫描时间(折算成采集相同有效层数的扫描时间)。结果 50例TOF-MOTSA28(20%)-TONE-MT块交界处"血管中断",其他序列无"血管中断"现象;50例TOF-MOTSA28(28.57%)-TONE-MT的采集时间最长,48例图像完整、均匀地显示出容积动脉、相邻块之间血管移行平滑;45例TOFMOTSA40(20%)-TONE-MT图像完整、均匀地显示出容积动脉、相邻块之间血管移行平滑;33例TOF-MOTSA56(20%)-TONE-MT的平行走行血管信号减低;35例TOF-MOTSA40(20%)-MT的流出端信号减低;50例TOF-MOTSA40(20%)-TONE采集时间最短,其中36例末梢血管信号降低或消失。结论应用3D-TOF-MRA序列进行颅脑血管成像时多种技术组合应用能更有效地减轻血流饱和效应,增强慢速血流和末梢血流信号;多种技术的合理配置能在保证图像质量的同时进一步缩短扫描时间。Objective To explore the effects of combination of multiple techniques including MOTSA （Multiple Overlapped Thin Slab Acquisition）, TONE （Tilt Optimized Non-saturation Excitation） and MT （Magnetization Transfer） on TOF-MRA （Time-of-lfight Magnetic Resonance Angiography） imaging quality and the scanning time. Methods TOF-MRA was performed in 50 healthy volunteers recruited in this study with deployment of six different scanning sequences so as to obtain the original images, and MIP （Maximum Intensity Projection） reconstruction was applied thereafter. The six scanning sequences included TOF-MOTSA28（20%）-TONE-MT, TOF-MOTSA28（28.57%）-TONE-MT, TOF-MOTSA40（20%）-TONE-MT, TOF-MOTSA56（20%）-TONE-MT, TOF-MOTSA40（20%）-MT and TOF-MOTSA40（20%）-TONE （MOTSA28, MOTSA40 and MOTSA56 indicated that the number of slice per thin slab was 28, 40 and 56 respectively;whereas 20%or 28.57%referred to the proportion of the overlapped thin slab）. Then, comparisons were made among MIP-reconstructed images obtained using the six scanning sequences in the completeness, uniformity, smoothness in vascular transition between adjacent slabs and the time consumed in each scanning procedure （the scanning time herein is deifned as the time consumed in scanning under the same number of effective slice）. Results Vessel interruption was shown at the junction of the slab in 50 MIP-reconstructed images obtained in the sequence of TOF-MOTSA28（20%）-TONE-MT; whereas no vessel interruption was found in images obtained in other sequences. Scanning with the sequence of TOF-MOTSA28（28.57%）-TONE-MT in 50 volunteers was the most time-consuming in comparison with those with other sequences;among 50 images obtained in the sequence of TOF-MOTSA28（28.57%）-TONE-MT, 48 had complete and uniform manifestations of volume arteries and smooth vascular transition between adjacent slabs. MIP-reconstructed images obtained with the sequence of TOF-MOTSA40（20%）-TONE-MT in 45 volunteers were complete and uniform in

关 键 词：时间飞跃法磁共振血管成像 重叠多个簿层块采集 倾斜优化非饱和激励 磁化传递 最大密度投影重建 1 5T磁共振扫描仪 

分 类 号：R445.2[医药卫生—影像医学与核医学] R811.1[医药卫生—诊断学]