小视野四翻转恢复成像技术在颈动脉粥样硬化高分辨MRI增强扫描中的应用(英文)  

Scan time reduction with a small field-of-view quadruple inversion-recovery high-resolution contrast-enhanced MRI for carotid atherosclerosis

作　　者：王庆军[1,2] 王勇[3] 蔡剑鸣[2] 蔡幼铨[2] 刘丹青[2] 韩旭[2] 

机构地区：[1]解放军海军总医院医学影像科,北京100037 [2]解放军总医院放射科,北京100853 [3]解放军252医院放射科,河北保定071000

出　　处：《南方医科大学学报》2013年第1期1-7,共7页Journal of Southern Medical University

基　　金：Supported by Military Research Plan of General Program during the 12th Five-Year Plan Period(CWS11J065)~~

摘　　要：目的为缩短扫描时间,在颈动脉高分辨磁共振对比增强中使用小视野四翻转恢复成像技术(SF-QIR),并评价其成像质量。方法 24例颈动脉斑块患者在同一台3.0T磁共振仪上进行颈动脉高分辨SF-QIR和常规矩形相位编码四翻转恢复(SrF-QIR)增强扫描。两种扫描序列间,除相位编码数量及射频脉冲激励方式不同外,其他扫描参数均一致。由3名独立的评价人对两种序列图像分别进行定性及定量评价。定性评价指标为颈动脉外部管壁轮廓、纤维帽及富脂质坏死核轮廓、诊断信心。定量评价指标为最大狭窄程度、管壁面积、富脂质坏死核面积、信噪比、对比噪声比。结果相对于SrF-QIR,使用正交射频脉冲技术的SF-QIR缩短近一半的扫描时间。除了信噪比与对比噪声比外,两种序列图像间各种定性及定量评价指标均无统计学差异(P>0.05)。相对于SrF-QIR,SF-QIR损伤了37.7%的信噪比(P<0.001)。结论颈动脉高分辨小视野QIR增强扫描技术可以有效评价颈动脉斑块形态学特征,并且能够明显缩短扫描时间及减少运动伪影。Objective To reduce the acquisition time of carotid high-resolution contrast-enhanced magnetic resonance imaging （CEMRI）, we designed a small field-of-view （FOV） quadruple-inversion-recovery （SF-QIR） T1WI and evaluated the image quality. Methods Twenty-four subjects with carotid plaque were enrolled in our study. All the subjects were imaged using the same 3.0T MRI by SF-QIR and standard rectangular FOV QIR （SrF-QIR） with identical parameters except for the phase-encoding step numbers and the RF excitation methods. Three independent readers qualitatively evaluated the differences between the two sequences in regard of the carotid outer wall border delineation, fibrous cap and lipid-rich necrotic core （LR-NC） border delineation, and diagnostic confidence. The quantitative measurements included maximal stenosis, wall area, LR-NC area, signal-to-noise ratio （SNR）, and contrast-to-noise ratio （CNR）. The inter-reader variability was assessed. Results The application of SF-QIR combined with orthogonal radio frequency excitation resulted in nearly half of the scan time with the SrF-QIR. Both qualitative and quantitative assessment by the readers revealed no significant differences between the two sequences except for SNR and CNR （P〉0.05）. Since the mean loss of SNR with SF-QIR was 37.7%, SrF-QIR demonstrated a superior performance in SNR （P〈0.001）. Conclusion The small FOV QIR sequence is effective in high-resolution CEMRI for evaluating carotid plaques and can effectively reduce the scan time and eliminate motion artifacts.

关 键 词：磁共振 颈动脉 粥样硬化 矩形视野 

分 类 号：R543.4[医药卫生—心血管疾病]