Department of Radiology, Seoul National University College of Medicine, Seoul, Korea.
Center for Nanoparticle Research, Institute for Basic Science, Seoul, Korea.
Korean J Radiol. 2021 Aug;22(8):1352-1368. doi: 10.3348/kjr.2020.1201. Epub 2021 May 4.
For an accurate dynamic contrast-enhanced (DCE) MRI analysis, exact baseline T1 mapping is critical. The purpose of this study was to compare the pharmacokinetic parameters of DCE MRI using synthetic MRI with those using fixed baseline T1 values.
This retrospective study included 102 patients who underwent both DCE and synthetic brain MRI. Two methods were set for the baseline T1: one using the fixed value and the other using the T1 map from synthetic MRI. The volume transfer constant (K), volume of the vascular plasma space (v), and the volume of the extravascular extracellular space (v) were compared between the two methods. The interclass correlation coefficients and the Bland-Altman method were used to assess the reliability.
In normal-appearing frontal white matter (WM), the mean values of K, v, and v were significantly higher in the fixed value method than in the T1 map method. In the normal-appearing occipital WM, the mean values of v and v were significantly higher in the fixed value method. In the putamen and head of the caudate nucleus, the mean values of K, v, and v were significantly lower in the fixed value method. In addition, the T1 map method showed comparable interobserver agreements with the fixed baseline T1 value method.
The T1 map method using synthetic MRI may be useful for reflecting individual differences and reliable measurements in clinical applications of DCE MRI.
为了进行准确的动态对比增强（DCE）MRI 分析，精确的基线 T1 映射至关重要。本研究旨在比较使用合成 MRI 的 DCE MRI 的药代动力学参数与使用固定基线 T1 值的参数。
这项回顾性研究纳入了 102 例行 DCE 和合成脑部 MRI 的患者。基线 T1 有两种方法：一种是使用固定值，另一种是使用合成 MRI 的 T1 图。比较两种方法的容积转移常数（K）、血管血浆容积（v）和细胞外间隙容积（v）。使用组内相关系数和 Bland-Altman 方法评估可靠性。
在正常表现的额白质（WM）中，固定值方法的 K、v 和 v 的平均值明显高于 T1 图方法。在正常表现的枕 WM 中，固定值方法的 v 和 v 的平均值明显更高。在壳核和尾状核头部，固定值方法的 K、v 和 v 的平均值明显较低。此外，T1 图方法与固定基线 T1 值方法具有可比的观察者间一致性。
使用合成 MRI 的 T1 图方法可能有助于反映 DCE MRI 临床应用中的个体差异和可靠测量。
