Department of Radiology, First Hospital of Shanxi Medical University, Taiyuan 030001, Shanxi Province, China.
Department of Radiology, First Hospital of Shanxi Medical University, Taiyuan 030001, Shanxi Province, China.
Clin Radiol. 2019 Apr;74(4):314-320. doi: 10.1016/j.crad.2018.12.004. Epub 2019 Feb 14.
To compare the value of diffusion kurtosis imaging (DKI) and diffusion tensor imaging (DTI) in evaluating astrocytomas with an isocitrate dehydrogenase (IDH) genotype.
Fifty-eight astrocytomas were divided into IDH-wild-type (IDH-W) and IDH-mutant (IDH-M) groups, in all astrocytomas, low-grade astrocytomas (LGA) and high-grade astrocytomas (HGA), respectively. The DKI (mean kurtosis [MK], radial kurtosis [Kr], axial kurtosis [Ka]), and DTI (fractional anisotropy [FA], mean diffusivity [MD]) values were measured. The differences of parameter values between the IDH-W and IDH-M groups were compared by t-test. Receiver operating characteristic (ROC) curves were used to identify the best parameter and z-score tests were used to compare the performance between DKI and DTI.
In all astrocytomas, MK, Ka, and Kr values were significantly higher (p<0.001, p=0.002, and p<0.001), and the MD value (p=0.005) was lower in the IDH-W group than those in the IDH-M group. The areas under the ROC curve (AUC) of MK (0.811) and Kr (0.800) were significantly higher than that of MD (0.704). In LGA, MK, Ka, and Kr values were also significantly higher in the IDH-W group than those in the IDH-M group (p=0.002, p=0.008, p=0.006), whereas MD and FA values showed no differences. In HGA, MK and Kr values were significantly higher (p=0.008, p=0.003), and the MD value (p=0.031) was significantly lower in the IDH-W group than that in the IDH-M group, the AUC of MK (0.750) and Kr (0.788) were also higher than MD (0.637; p=0.032, p=0.025).
DKI may be a new imaging biomarker for evaluating the IDH genotype of astrocytomas, which is more accurate and stable than DTI.
比较扩散峰度成像（DKI）和扩散张量成像（DTI）在评估异柠檬酸脱氢酶（IDH）基因型星形细胞瘤中的价值。
将 58 例星形细胞瘤分为 IDH 野生型（IDH-W）和 IDH 突变型（IDH-M）组，在所有星形细胞瘤中，低级别星形细胞瘤（LGA）和高级别星形细胞瘤（HGA），分别测量 DKI（平均峰度[MK]、径向峰度[Kr]、轴向峰度[Ka]）和 DTI（各向异性分数[FA]、平均弥散度[MD]）值。用 t 检验比较 IDH-W 组和 IDH-M 组之间参数值的差异。采用受试者工作特征（ROC）曲线识别最佳参数，用 z 检验比较 DKI 和 DTI 的性能。
在所有星形细胞瘤中，IDH-W 组的 MK、Ka 和 Kr 值明显较高（p<0.001、p=0.002 和 p<0.001），MD 值较低（p=0.005）。ROC 曲线下面积（AUC）MK（0.811）和 Kr（0.800）明显高于 MD（0.704）。在 LGA 中，IDH-W 组的 MK、Ka 和 Kr 值也明显高于 IDH-M 组（p=0.002、p=0.008、p=0.006），而 MD 和 FA 值无差异。在 HGA 中，IDH-W 组的 MK 和 Kr 值明显较高（p=0.008、p=0.003），MD 值明显较低（p=0.031），AUC 的 MK（0.750）和 Kr（0.788）也高于 MD（0.637；p=0.032、p=0.025）。
DKI 可能是一种评估星形细胞瘤 IDH 基因型的新成像生物标志物，其比 DTI 更准确、稳定。
