Abstract：Objective: To study differential diagnosis value in the benign and malignant solitary pulmonary nodule(SPN) by dynamic contrast-enhanced(DCE) and diffusion weighted imaging(DWI) of magnetic resonance imaging(MRI). Methods: The 62 SPN patients were firstly examined by routine T1WI, T2WI and DWI, secondly by DCE-MRI, including 35 malignant and 27 benign lesions. The ADC values were measured of different b values at work station, the curve types were observed according to Schaefer standard, steepest slope(SS) and washout ratio(WR) were calculated. The sensitivity, specificity and accuracy in the diagnosis of malignant SPN were evaluated. Results: The curve types were not significantly different between benign and malignant SPNs(P＞0.05); The B type curve was overlap, the SS was significantly different between them(P<0.05); It had a sensitivity of 64％, a specificity of 60％ and a accuracy rate of 62% for malignant SPN diagnosis according to SS value being more than 2.5%/s; The ADC values of SPNs were significantly different at b 800 s/mm2 and 1 000 s/mm2 with B curve type(P<0.05). Combination of DCE and DWI, it had a sensitivity of 80％, a specificity of 75％ and a accuracy rate of 78% for malignant SPN diagnosis according to ADC value being less than 1.34×10-3 mm2/s. Conclusion: The differential diagnosis of benign and malignant SPN is significant by DCE and DWI respectively. Combined application of DCE and DWI can improve the accuracy of diagnosis of malignant SPN．
2015, Vol. 26 
