Institute of Radiology, University Hospital Erlangen, Maximiliansplatz 3, 91054 Erlangen, Germany.
Department of Medical Biometry, Informatics and Epidemiology, University Hospital Bonn, Bonn, Germany; Institute of Medical Informatics, Biometry and Epidemiology, University of Erlangen, Erlangen, Germany.
Acad Radiol. 2020 May;27(5):744-749. doi: 10.1016/j.acra.2019.07.013. Epub 2019 Aug 26.
Differences in brain signal intensity ratios (SIRs) of deep brain nuclei in T1-weighted (T1w) magnetic resonance images were reported as an indicator of gadolinium brain retention. Variable methods of image reconstruction and inhomogeneity correction for T1w images exist, which might affect the accuracy of SIRs. The aim of our prospective study was to investigate the effect of flow artifact compensation (FAC) and intensity inhomogeneity correction (IIC) on the dentate nucleus-to-pons and globus pallidus-to-thalamus SIRs in study participants who had previously received multiple doses of gadobutrol.
This study included 76 participants who received five or more gadobutrol-enhanced scans between 2007 and 2017. A control group of 25 participants without gadolinium-based contrast agent application in their patient history was included for comparison. Unenhanced brain magnetic resonance imaging including two T1w spin-echo sequences with and without FAC was performed in all participants. Both sequences were reconstructed with and without IIC. Images were assessed for flow artifacts and SIRs were calculated.
Using FAC, a lower proportion of participants had to be excluded from the final analysis of dentate nucleus-to-pons SIR due to flow artifacts (15% versus 46%, p < 0.001). Without IIC, a difference was found between the study and the control group for the dentate nucleus-to-pons ratio (p = 0.004), but not for the same sequence reconstructed with IIC (p = 0.29). For the globus pallidus-to-thalamus ratio, no difference was found between the study and control group.
The application of an IIC algorithm has significant impact on brain nuclei SIRs for the assessment of gadolinium brain retention.
据报道，在 T1 加权（T1w）磁共振图像中，深部脑核的脑信号强度比（SIR）的差异是钆脑潴留的一个指标。T1w 图像的图像重建和不均匀性校正方法存在差异，这可能会影响 SIR 的准确性。我们的前瞻性研究旨在研究流动伪影补偿（FAC）和 T1w 图像不均匀性校正（IIC）对先前接受多次多布醇钆增强扫描的研究参与者的齿状核-脑桥和苍白球-丘脑 SIR 的影响。
本研究纳入了 76 名参与者，他们在 2007 年至 2017 年间接受了五次或更多次多布醇钆增强扫描。纳入了一组 25 名无钆基造影剂应用史的参与者作为对照组进行比较。所有参与者均进行了包括两个 T1w 自旋回波序列的未增强脑磁共振成像，包括有无 FAC。这两个序列都进行了有无 IIC 的重建。评估图像的流动伪影并计算 SIR。
使用 FAC，由于流动伪影，有更低比例的参与者需要从最终的齿状核-脑桥 SIR 分析中排除（15%对 46%，p<0.001）。没有 IIC，研究组和对照组之间的齿状核-脑桥比率存在差异（p=0.004），但 IIC 重建的相同序列则无差异（p=0.29）。对于苍白球-丘脑比率，研究组和对照组之间没有差异。
IIC 算法的应用对评估钆脑潴留的脑核 SIR 有显著影响。
