Applications of MRI in pediatric patients with secandum atrial septal defects
SUN Ai-min1, DING Wen-long2, ZHU Ming1, ZHONG Yu-min1, WANG Qian1
1. Department of Radiology, Shanghai Children’s Medical Center of Shanghai Jiaotong University, School of Medicine,Shanghai 200127, China; 2. Shanghai Jiaotong University, School of Medicine, Shanghai 200127, China
摘要目的：评价MRI在继发孔房间隔缺损（ASD）诊断中的应用价值。方法：21例经胸超声心动图（TTE）证实为继发孔ASD患儿，平均年龄6.26岁 （2~15岁），平均心率106次/min。扫描序列包括真稳态进动快速成像序列（FIESTA），相位流速编码技术（PC-MRI）测量ASD的直径， CE-MRA进行血管造影。结果：21例均为继发孔ASD，2例伴肺静脉异位引流。21例中9例完成房间隔堵塞装置封堵治疗，4例行外科手术纠治。4例PC-MRI测得ASD形态，大小，与上腔静脉、下腔静脉、三尖瓣距离与术中所见吻合。PC-MRI测得ASD直径与TTE测得直径有较好的相符性（斜冠状位直径r=0.948，P<0.001，横径r=0.878，P<0.001）。9例完成介入治疗术中测得封堵装置的直径略大于PC-MRI结果[(10.33±4.34）cm vs （9.68±3.92cm)]（r=0.954，P<0.001）。结论：MR可直观显示ASD形态，准确测量其大小及与周围重要解剖结构的关系，检测出伴发畸形，对TTE起重要补充作用，甚至可替代TTE作为继发孔ASD介入治疗前的影像诊断方法。
Abstract：Objective: To evaluate the value of MRI in pediatric patients with secundum atrial septal defects(ASD). Methods: Twenty-one cases with secundum ASD (mean age 6.26 years; age range from 2 to 15 years) were evaluated by MRI including FIESTA, phase-contrast MRI and CE-MRA. Results: Of all the 21 cases with secundum ASD, 2 cases associated with partial anomalous pulmonary venous return, which was missed by transthoracic echocardiography(TTE) were detected by MRI. Nine cases underwent transcather closure of the ASD. Four had surgical repair. Measurements at PC-MRI of ASD size and septal rim distances to superior vena cava, inferior vena cava, tricuspid valve, right upper pulmonary vein in 4 cases agreed fairly well with surgical results. Measurements of defect sizes at phase-contrast MR had good agreement with measurements at TTE. The device size after closure of ASD in 9 cases was little larger than measurements at PC-MRI. Conclusion: MR imaging can enable determination of defect size, rim distances to adjacent structures, and anomalous pulmonary venous connections, which can provide some complementary information to TTE and even can be considered as an alternative diagnostic method to TTE before transcather closure of ASD.
2009, Vol. 20 
