目的 评估肺部DKI的可行性， 比较DKI和标准DWI 在鉴别良、恶性肺结 节的应用价值。方法 分别利用DKI(b值 为0,500,和1000s/mm2 )和标准DWI(b值为 0和800s/mm2 )评估了32例患者(共35个肺 结节)。两名医师独立评估并比较了平均 弥散峰度(MK)和ADC值区分恶性和良性肺 结节的准确性。对于各参数值，我们还 评估了两名观测者内和观测者之间的可 重复性(同类相关系数，ICC)。结果 对 于恶性和良性肺结节的鉴别，MK(Obs. 1a:85.70%,0.87; Obs.1b:80.00%, 0.80;Obs.2:82.80%,0.91)的诊断准 确性和曲线下面积并没有显著高于 ADC值(Obs.1a:77.14%,0.81;Obs.1b: 80.00%,0.85;Obs.2:77.14%,0.85)。对 于恶性和良性肺结节，两位观测者内和 观测者间一致性(ICC)都较高。结论 本 文的初步结果显示，DKI可用于诊断肺部 病变，其MK值在鉴别肺恶性和良性结节 方面与ADC值相比提供更多临床信息。

Objective Diffusion-weighted imaging (DWI) derived apparent diffusion coefficient (ADC) has demonstrated incon- sistent results in pulmonary nodule differentiation. Diffusion kurtosis imaging (DKI), which quantifies non-Gaussian diffusion, is believed to better characterize tissue micro-structure than conventional DWI. Purpose: To assess the feasibility of DKI in human lungs and to compare its diagnostic value with standard DWI in differentiating malignancies from benign pulmonary nodules. Methods Thirty-five pulmonary nodules in 32 consecutive patients were evaluated by DKI by using 3b- values of 0, 500, and 1000s/mm2 and conventional DWI with b values of 0 and 800s/mm2 . Two observers independently evaluated and compared diagnostic accuracy of mean kurtosis (MK) and ADC values in differentiating malignancies from benign pulmonary nodules. The intra- and inter-observer repeatability (intra-class correlation coefficient [ICC]) were also assessed for each derived measures. Results The diagnostic accuracy, and the area under curve (AUC) in differentiating malignancies from benign pulmonary nodule, were not significantly higher for MK (Obs. 1a: 85.70%, 0.87; Obs. 1b: 80.00%, 0.80; and Obs. 2: 82.80%, 0.91) as compared to ADC (Obs. 1a: 77.14%, 0.81; Obs. 1b: 80.00%, 0.85; and Obs. 2: 77.14%, 0.85 respectively). The intraand inter-observer agreement (ICC) for malignant and benign lesions was substantial for each reading. Conclusion The initial results of this study indicate the feasibility of DKI in human lungs. MK values provide more clinical in formation than ADC values for differential diagnosis of malignant and benign pulmonary nodule。