Multi Technical MRI Diagnosis For Complex Congenital Heart Disease

PartⅠhigh-field MRI, "one-stop-shop" for complex congenital heart diseaseSection 1 The value of "one-stop-shop" 1.5T MRI for the diagnosis of complex congenital heart diseaseObjective:To evaluate the value of plain MRI, cine MRI compounded with 3D CEMRA ("one-stop-shop" MRI) for the diagnosis of complex congenital heart disease.Materials and Methods:33 patients with complex congenital heart disease, who has undergone Echo examination but without satisfied diagnosis, were enrolled in this research. 2D SSFP sequence, SE sequence, cine SSFP sequence and 3D FLASH sequence were performed. The MRI images of every patient were divided into two groups, group A contains plain MRI, cine MRI while group B contains 3D CEMRA besides.The diagnosis of both group were compared with Echo examination.Results:There were 22 patients on whom the MRI examinations was completed and of whom the results was confirmed by operation. Of the 108 malformations in all, there were 45 intra cardiac malformations and 63 extra cardiac malformations. The diagnostic accuracy of group A, group B and Echo examination for all malformations/intra cardiac malformations/extra cardiac malformations is 85.2%/84.4%/85.7%,91.7%/84.4%/96.8% and 85.2%/88.9%/79.4% separately.Conclusion:MRI,cine MRI compounded with 3D CEMRA can absolutely improve the diagnostic accuracy of extra cardiac malformations, but help little for diagnostic accuracy of intra cardiac malformations. Compared with Echo examination, both MRI examination styles are better for the diagnosis of extra cardiac malformations, but are of less value for intra cardiac malformations.Section 23.0T versus 1.5T MRI for congenital heart diseaseObejective:To evaluate the value of 3.0T MRI for children with complex congenital heart disease, compared with 1.5T MRI.Materials and Methods:110 children with complex congenital heart disease, who has undergone Echo examination but without further details for extra cardiac anomalies were randomly examined by 3.0T MRI and 1.5T MRI. Cine Steady State Free Precession (cine SSFP), three dimensional fast low angle shot imaging (3D FLASH) and other sequence for compensation were performed. The image quality and diagnosis was compared to evaluate the value of 3.0T MRI for complex congenital heart disease.Results:103 children were successfully examined and 61 of them were confirmed by operation. The image quality of 3.0T,1.5T MRI for either intra or extra cardiac anomalies of all patients scored3, which allowed establishment of a diagnosis for all cases. The image quality of 3.0T MRI was significantly higher than 1.5T while there was no significant difference between them for extra cardiac anomalies. The detection rate and specificity of 3.0T MRI,1.5TMRI and Echo intra cardiac anomalies were 95.7%,97.1%; 92.5%,98.0%; 98.4%,98.4%, and for extra cardiac anomalies 86.5%,88.2%; 86.0%, 94.2%; 87.0%,85.1%, respectively. Compared with 1.5TMRI,3.0T detected more anomalies for both intra and extra malformations, but with no significance. Compared with Echo,3.0T MRI detected less anomalies for intra cardiac anomalies, and detected significant more anomalies for extra cardiac anomalies.Conclusion:The image quality and diagnostic value of 3.0TMRI for children with complex congenital heart disease is relatively higher than 1.5T. Compared with Echo,3.0T MRI remains to be improved for diagnosis for intra cardiac anomalies, but has significant higher value for extra cardiac anomalies.PartⅡUnenhanced three dimensional steady state free precession (3D SSFP) magnetic resonance imaging (MRI) for congenital heart diseaseSection 1 Unenhanced Three Dimensional Steady State Free Precession versus Conventional Magnetic Resonance Imaging Technique for Congenital Heart DiseaseObjective:To assess potential benefits of three dimensional (3D) steady state free precession (SSFP) magnetic resonance sequence for congenital heart disease (CHD).Material and Methods:20 consecutive patients with CHD (male:female ratio,14:6, mean age,25.6±14.5 years) underwent both 3D SSFP and conventional MR imaging (CMRI) [mainly included two dimensional (2D) SSFP and contrast enhanced magnetic resonance angiography (CE MRA)], the image quality and diagnosis were compared, and Bland-Altman analysis was used to evaluate consistency of 3D SSFP and CE MRA for diameter measurements.Results:All patients including tetralogy of Fallot (F4) (n=6), postoperative F4 (n=4), right coranary-right atrium fistula (n=1), highly dilated pulmonary artery (n=1) and other complicated CHD (n=8) totally got 35 intra and 81 extra cardiac anomalies. The image quality of 3D SSFP and CMRI for either intra or extra cardiac anomalies of all patients scored≥3, which allowed an establishment of diagnosis for all cases. The diagnostic sensitivity, specificity, and accuracy of 3D SSFP for the detection of intra cardiac anomalies were all 100%, while for extra cardiac anomalies were 93.8%,93.8%,100%, respectively. Mean differences (3D SSFP minus CE MRA) for aorta and pulmonary arteries are 0.05±0.12 and 0.00±0.17 respectively, showing good consistency of 3D SSFP and CEMRA for diameter measurements.Conclusion:3D SSFP MRI provides powerful information that complements CMRI for congenital heart disease, especially at ventriculoarterial connection site. It can also be an alternative to CMRI for patients who have renal insufficiency, breath-hold difficulty or are sensitive to contrast agent.Section 2 Unenhanced 3D steady state free precession magnetic resonance angiography for the assessment of congenital heart diseasesObjective:To evaluate the feasibility of free breathing unenhanced three dimensional steady state free precession (3D SSFP) magnetic resonance angiography (MRA) in the assessment of congenital heart diseases (CHD).Materials and methods:54 consecutive patients underwent whole chest 3D SSFP MRA, and were divided into three groups:CHD group (n=18), healthy group (n=20) and cardiomyopathy group (n=16). Image quality (IQ) of aorta, pulmonary artery, coronary arteries among the three groups and inter the CHD group was compared.Results:Every individual IQ of aorta, pulmonary artery and coronary artery in CHD group scored≥3, which allowed establishment of a diagnosis in all cases. There were no significant difference in IQ between CHD group and healthy group for all aorta, pulmonary and coronary arteries (P=0.11-0.99), while the IQ of pulmonary, coronary arteries in CHD group were significantly higher than cardiomyopathy group (P<0.05).2. For CHD group, there were no significant difference in IQ among aorta, pulmonary, coronary arteries (P=0.44～0.87) or among the segments or branches of them (P=0.25-1.00).Conclusion:Isotropic whole-chest 3D SSFP MRA for congenital heart diseases allows reliable discrimination of aorta, pulmonary, coronary arteries abnormalities, the image quality is almost the same as healthy people, and is stable among aorta, pulmonary, coronary arteries and the segments or branches of them. It has great promise in MRA for CHD patients. PartⅢThe value of noncontrast three dimensional steady state free precession (3D SSFP) magnetic resonance Angiography (MRA) for thoratic cardiovascular disordersObjective:To evaluate the feasibility of three-dimensional steady state free precession (3D SSFP) magnetic resonance imaging (MRI) for the assessment of thoratic cardiovascolar disorders, and correlate the results with conventional magnetic resonance imaging(CMRI).Materials and methods:22 consecutive patients suspected with various cardiac and thoracic vascular diseases underwent both 3D SSFP and CMRI, the image quality and diagnosis was compared, and Bland-Altman analysis was used to evaluate consistency of the two scan style for cadiac champer measurments.Results:1.The image quality of both 3D SSFP and CMRI for all patients score3,which allows establishment of a diagnosis in all cases.2.For cardiovascular morphology disorders, both 3D SSFP and CMRI can make cerrect diagnosis.and the former is better in diagnosis of cardiac-vessel-junction malformations, pricardial effusion and intracrdiac thrombus,which is sometimes difficult for CMRI.3. The mean differences (CMRI minus 3D-SSFP)and lower/upper limits of agreement of atrial and ventricular diameters are -0.11, (-0.52cm,0.30cm) and -0.01,(-0.66cm,0.64cm).separataly,showing good agreement in cardiac champer measurements,thus 3D-SSFP MRI can be an altelative method for cardiac champer measurements.Conclusion:Free breathing navigator-gated noncontrast 3D SSFP MRI with nonselective radiofrequency excitation provides high image quality and more information for diagnosis of thoratic cardiovascular disorders, and is an alterlative MRI for CMRI in patients with breath-hold difficulty or renal insufficiency.