心脏磁共振实时单次采集电影成像在分析左室功能中的应用

Application of single-shot real-time cine CMRI for left ventricular function

目的对比实时单次采集(Real-time Single-shot)快速电影序列与传统分段采集电影成像,探索此电影序列分析左室功能及测量左室室壁厚度的可行性和准确性。方法选择健康自愿者32例,3.0T磁共振仪32通道心脏线圈采集,分别行左Real-time Single-shot快速电影序列与传统分段采集梯度回波电影成像序列,扫描层面对应,将左室分为16阶段,对比两组LVEF、LVEDV、LVESV、LVSV、LVCO、左室室壁厚度的差别。结果评价LVEF、LVSV、LVCO时real-timeMRI技术与传统梯度回波电影成像序列P>0.05有很好的一致性。而LVEDV左室舒张末期容积及LVESV左室收缩末期容积P<0.05存在统计学差异。节段室壁厚度除5节段P=0.05,第11节段P=0.048,P<0.05外,其他节段均P>0.05。结论 Real-time电影MRI能够在生理范围的心率被用于准确量化整个心动周期的左室容积,左室室壁厚度,减少心脏MRI检查的必须时间。

Objective To compare an accelerated real-time single-shot cine sequence with a conventional segmented cine sequence for imaging the heart and to evaluate its feasibility and accuracy for quantification of left ventricular（ LV） function and mass. Methods 32 healthy volunteers underwent real-time single-shot balanced steady-state free precession（ SSFP） cine imaging on a 3. 0 T scanner with a 32-channel coil. A conventional 2D segmented SSFP sequence was used as the reference standard.Plane orientation was identical with both sequences. For analysis,the American Heart Association 16-segment model was used.Left ventricular volumes,including ejection fraction（ EF）,end-diastolic volume（ EDV）,end systolic volume（ ESV）,stroke volume（ SV）,cardiac output（ CO） and myocardial mass,were compared. Results LVEF,LVSV,and LVCO were significantly correlated with those of the standard sequence（ P〉0,05）. However,a significant difference was shown for LVEDV and LVSV（ P〈0. 05）. Wall thicknesses were concordant with the standard sequence except 5th（ P = 0. 05） and 11th（ P〈0. 05） segments for the accelerated single-shot protocol,（ P〉0. 05）. Conclusion Accelerated real-time single-shot SSFP cine sequence is comparable to the standard clinical sequence in assessment of left ventricular function and thickness with substantially reduced scan time.