Cardia Patricia P, Penachim Thiago J, Prando Adilson, Torres Ulysses S, D'Ippólito Giuseppe
1 Department of Diagnostic Imaging, Federal University of São Paulo (Universidade Federal de São Paulo-UNIFESP), Paulista School of Medicine, São Paulo, Brazil.
2 Centro Radiológico Campinas, Vera Cruz Hospital, São Paulo, Brazil.
Br J Radiol. 2017 Jul;90(1075):20170011. doi: 10.1259/bjr.20170011. Epub 2017 Jun 7.
Although non-contrast MR angiography (NC-MRA) is well established for the evaluation of renal artery stenosis, its usefulness in the evaluation of other abdominal aortic branches remains to be studied. This study aimed at evaluating the image quality and diagnostic accuracy of NC-MRA using a three-dimensional balanced steady-state free-precession sequence in identifying stenosis in the celiac trunk (CTR) and superior mesenteric artery (SMA) as compared with CT angiography (CTA) as the reference standard.
41 patients underwent both NC-MRA and CTA of the abdominal aorta. Two radiologists analyzed the quality of the images (diagnostic vs non-diagnostic) and the performance (accuracy, sensitivity and specificity) of NC-MRA for the identification of arterial stenosis. Kappa tests were used to determine the interobserver agreement and the intermethod agreement between NC-MRA and CTA.
NC-MRA provided diagnostic quality images of the CTR and SMA in 87.8% and 90.2% of cases, respectively, with high interobserver agreement (kappa 0.95 and 0.80, respectively). For stenosis assessment, NC-MRA had a sensitivity of 100%, a positive-predictive value of 50% and a negative-predictive value of 100% for both segments, with accuracies of 88.8% for the CTR and 94.5% for the SMA.
NC-MRA is an accurate method for detecting stenosis in the CTR and SMA. Advances in knowledge: Data from this study suggest that MR angiography with balanced steady-state free-precession sequence is a viable non-contrast alternative for stenosis evaluation of these branches in patients for whom a contrast-enhanced examination is contraindicated.
尽管非增强磁共振血管造影(NC-MRA)在评估肾动脉狭窄方面已得到广泛应用,但其在评估其他腹主动脉分支方面的效用仍有待研究。本研究旨在使用三维平衡稳态自由进动序列评估NC-MRA在识别腹腔干(CTR)和肠系膜上动脉(SMA)狭窄方面的图像质量和诊断准确性,并与作为参考标准的CT血管造影(CTA)进行比较。
41例患者接受了腹主动脉的NC-MRA和CTA检查。两名放射科医生分析了图像质量(诊断性与非诊断性)以及NC-MRA在识别动脉狭窄方面的性能(准确性、敏感性和特异性)。使用Kappa检验来确定观察者之间以及NC-MRA与CTA之间的方法间一致性。
NC-MRA分别在87.8%和90.2%的病例中提供了CTR和SMA的诊断质量图像,观察者间一致性较高(分别为kappa 0.95和0.80)。对于狭窄评估,NC-MRA对两个节段的敏感性均为100%,阳性预测值为50%,阴性预测值为100%,CTR的准确性为88.8%,SMA的准确性为94.5%。
NC-MRA是检测CTR和SMA狭窄的准确方法。知识进展:本研究数据表明,对于禁忌进行对比增强检查的患者,采用平衡稳态自由进动序列的磁共振血管造影是评估这些分支狭窄的一种可行的非增强替代方法。