MRI快速扫描技术在儿童先天性心脏病诊断中的应用

目的:探讨MRI半傅立叶采集单次激发快速SE(HASTE)序列、真稳态进动快速成像(TrueFISP)序列和并行采集技术在儿童先天性心脏病诊断中的应用价值.方法:对50例经超声心动图检查的先天性心脏病患儿进行心脏大血管MRI检查,其中26例行DSA检查,全部病例经手术证实.扫描序列包括HASTE、TrueFISP序列以及回顾性心电门控心血管电影成像,并加用并行采集技术.分析各序列MRI图像质量,并将MRI检查结果与超声心动图、DSA结果进行对照.结果:MRI共检出10种复杂先心共181处心血管畸形.26例行DSA检查共检出畸形120个并均与手术结果吻合,MRI显示畸形114个(95.00%),超声心动图检出畸形110个(92.67%).TrueFISP序列和HASTE序列利于显示血管畸形,电影序列有助于检出心内外分流.结论:HASTE黑血技术、TrueFISP亮血技术结合快速电影序列进行心脏MRI检查,可以获得高质量的图像以及较高的病变检出率,适用于儿童先天性心脏病的诊断.

Application of Magnetic Resonance Fast Scan Techniques in the Diagnosis of Congenital Heart Diseases in Children

Objective:To explore the clinical application of MR fast scan techniques,such as half-Fourier acquisition single shot spin echo(HASTE),true fast imaging with steady-state precession(TrueFISP),ECG triggered cine and integrated parallel acquisition technique(iPAT) in the diagnosis of congenital heart diseases in children.Methods:Cardiac MRI,echocardiography and surgical operation were performed in 50 cases of pediatric patients with complex congenital heart diseases.HASTE,TrueFISP,ECG triggered cine and iPAT techniques were included in the cardiac MRI scanning protocols.X-ray angiography was performed in 26 cases.The image quality and the examination results of MR imaging were analyzed.MRI findings were correlatively compared with those of the X-ray angiography and echocardiography.Results:High quality images were obtained with HASTE and TrueFISP scanning sequences.10 kinds of complex congenital heart diseases and 181 cardiovascular malformations were found by MRI in 50 cases.In the 26 cases with X-ray cardiovascular angiograms,120 surgically proven malformations were all revealed on angiograms,114 malformations(95%) were found on MRI scans,and 110 malformations(92.67%) on echocardiograms.The detection and diagnostic accuracy rates of MRI were higher than those of echocardiography.HASTE and TrueFISP sequences were beneficial for the detection of great vessel malformations and MR cardiovascular cine was helpful in the demonstration of shunts.Conclusion:Cardiovascular MRI scanning using a scanning protocol of dark blood HASTE and bright blood TrueFISP sequences in combination with cardiovascular cine technique,yielded high quality images and resulted in rather high malformation detection rate,therefore,it was recommended for the imaging examination and diagnosis of congenital heart diseases in children.