Experimental Study of Diffusion-weighted MRI for Discrimination of Inflammatory and Metastatic Lymph nodes

Objective To evaluate diffusion-weighteghted imaging(DWI) values for discrimination of inflammatory and metastatic lymph nodes in rabbit models.Methods Conventional MRI and DWI images were obtained from 40 rabbits,which were divided into two groups as lymphadenitis model and metastaic lymph node model.Apparent diffusion coefficient(ADC) values of lymph nodes were measured.The diagnostic value of ADC was analyzed by ROC curves.All lymph nodes were confirmed by pathology.Results The average ADC value of inflammatory and metastatic nodes was(0.859 ± 0.037) × 10 -3 mm2 /s and(1.089 ± 0.244) × 10 -3 mm2 /s.There was statistical difference between them(P 0.05).The area under the ROC curves was 0.791.Threshold value to distinguish benign and malignant lesions was 0.889 × 10 -3 mm2 /s.Sensitivity,specificity were 80%,75%,respectively.Conclusion DWI is an useful tool for discrimination of inflammatory and metastatic lymph nodes in VX2 rabbits.