Department of Radiology, Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, Peking University Cancer Hospital and Institute, No. 52 Fu Cheng Rd, Hai Dian District, Beijing, 100142, China.
Center for MR Research, and Department of Radiology, University of Illinois at Chicago, 2242 West Harrison Street, Suite 103, M/C 831, Chicago, IL, 60612, USA.
Eur Radiol. 2018 Mar;28(3):1301-1309. doi: 10.1007/s00330-017-5049-8. Epub 2017 Sep 19.
To investigate the value of an intravoxel incoherent motion (IVIM) diffusion model for discriminating malignant versus benign mediastinal lymph nodes (MLN).
Thirty-five subjects with enlarged MLN were scanned at 1.5 Tesla. Diffusion-weighted imaging was performed with eight b-values. IVIM parameters D, D*, and f, as well as apparent diffusion coefficient (ADC) from a mono-exponential model were obtained. 91 nodes (49 malignant and 42 benign) were analysed with pathologic (n=90) or radiologic (n=1) confirmations. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic performance.
The mean values of D, ADC, and f for the malignant group were significantly lower than those for the benign group (p<0.001), while D* showed no significant difference (p=0.281). In the ROC analysis, the combination of D and f produced the largest area under the curve (0.953) compared to ADC or other individual IVIM parameters, leading to the best specificity (92.9%) and diagnostic accuracy (90.1%).
This study demonstrates that the combination of IVIM parameters can improve differentiation between malignant and benign MLN as compared to using ADC alone.
• Diffusion MRI is useful for non-invasively discriminating malignant versus benign lymph nodes. • A mono-exponential model is not adequate to characterise diffusion process in lymph nodes. • IVIM model is advantageous over mono-exponential model for assessing lymph node malignancy. • Combination of IVIM parameters improves differentiation of malignant versus benign lymph nodes.
探讨体素内不相干运动（IVIM）扩散模型在鉴别纵隔良恶性淋巴结（MLN）中的价值。
35 例纵隔淋巴结肿大患者在 1.5T 进行扫描。采用 8 个 b 值进行扩散加权成像。获得 IVIM 参数 D、D*和 f 以及单指数模型的表观扩散系数（ADC）。对 91 个淋巴结（49 个恶性和 42 个良性）进行病理（n=90）或影像学（n=1）证实分析。采用受试者工作特征（ROC）分析评估诊断性能。
恶性组的 D、ADC 和 f 平均值明显低于良性组（p<0.001），而 D*无显著差异（p=0.281）。在 ROC 分析中，与 ADC 或其他单个 IVIM 参数相比，D 和 f 的组合产生了最大的曲线下面积（0.953），从而具有最佳的特异性（92.9%）和诊断准确性（90.1%）。
本研究表明，与单独使用 ADC 相比，IVIM 参数的组合可以提高对良恶性 MLN 的区分能力。
扩散 MRI 有助于非侵入性地鉴别良恶性淋巴结。
单指数模型不足以描述淋巴结的扩散过程。
IVIM 模型在评估淋巴结恶性程度方面优于单指数模型。
IVIM 参数的组合可改善良恶性淋巴结的区分。
