Non-Gaussian diffusion imaging for malignant and benign pulmonary nodule differentiation: a preliminary study.
BACKGROUND
Diffusion-weighted imaging (DWI) derived apparent diffusion coefficient (ADC) has demonstrated inconsistent 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.


MATERIAL AND METHODS
Thirty-five pulmonary nodules in 32 consecutive patients were evaluated by DKI by using 3b-values of 0, 500, and 1000 s/mm2 and conventional DWI with b values of 0 and 800 s/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 intra- and 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. However, there was no significant benefit of DKI derived MK values over ADC for malignant and benign pulmonary nodule differentiation.
['Das|Sushant Kumar|SK|', 'Yang|Dong Jun|DJ|', 'Wang|Jin Liang|JL|', 'Zhang|Chuan|C|', 'Yang|Han Feng|HF|']
D000328:Adult D000368:Aged D000369:Aged, 80 and over D000465:Algorithms D003198:Computer Simulation D003627:Data Interpretation, Statistical D038524:Diffusion Magnetic Resonance Imaging D005240:Feasibility Studies D005260:Female D006801:Humans D007089:Image Enhancement D007090:Image Interpretation, Computer-Assisted D008175:Lung Neoplasms D008297:Male D008875:Middle Aged D015233:Models, Statistical D010865:Pilot Projects D015203:Reproducibility of Results D012680:Sensitivity and Specificity D003074:Solitary Pulmonary Nodule D016008:Statistical Distributions
pulmonary nodule Diffusion kurtosis imaging lung cancer non-Gaussian imaging