Experimental study of VX2 rabbits metastatic and inflammatory adenopathy by using dynamic contrast-enhanced MR imaging

Objective To study the dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI ) features of VX2 rabbits carcinoma metastatic and inflammatory lymph nodes.Methods Twenty healthy adult New Zealand white rabbits were divided into metastatic lymph node group and inflammatory lymph node group randomly. There were ten rabbits in each group. All 20 rabbits underwent DCE-MRI.Peak enhancement,time to peak,maximum slope and signal intensity versus time curves were generated from each node individually.Results DCE-MRI were obtained for nine cases of metastatic lymph nodes and nine cases of inflammatory lymph nodes.The signal intensity versus time curves of metastatic lymph nodes were appeared as rapid ascending and plateauing,and peak enhancement,time to peak,maximum slope of metastatic lymph nodes group were 284％ ± 125％,(118 ±47) s and (6.5 ±2.7) ％/s,respectively.The signal intensity versus time curves of inflammatory lymph nodes were appeared as insisting ascending,and peak enhancement,time to peak,maximum slope of inflammatory lymph nodes group were 199％ ± 109％,( 143 ± 40) s and ( 3.6 ± 1.5 ) ％/s,respectively.There was significantly higher peak enhancement,shorter time to peak and higher maximum slope in the metastatic lymph nodes group compared with the inflammatory lymph nodes group (P ＜ 0.05 ). Conclusions DCE-MRI can accurately reflect the hemodynamic characteristics of VX2 rabbits neoplasm metastatic lymph nodes and inflammatory lymph nodes,and can differentiate VX2 rabbits neoplasm metastatic lymph nodes from inflammatory lymph nodes. Key words: Magnetic resonance imaging;  Neoplasm metastasis;  Lymph nodes;  Inflammation