Intravoxel incoherent motion MR imaging in nasopharyngeal carcinoma: comparison and correlation with dynamic contrast enhanced MR imaging

OBJECTIVES: To compare accuracy and assess agreement between intravoxel incoherent motion (IVIM) magnetic resonance (MR) perfusion-related parameters and quantitative dynamic contrast-enhanced (DCE) MR parameters in nasopharyngeal carcinoma (NPC). RESULTS: D, f, D*, K(trans), K(ep) and V(p) were significantly lower in the high stage group while V(e) was significantly higher in the high stage group. Optimal cut-off values were: D=0.749 × 10(−3) mm(2)/s; f=0.145; D*=100.401 × 10(−3) mm(2)/s; K(trans)=0.571/min; K(ep)=0.8196/min; V(e)=0.6556 %; V(p)=0.0757 %. D* (p=0.001), K(trans) (p<0.001), V(e) (p=0.014) were all reliable independent predictors for AJCC staging. IVIM-MR perfusion-related (f, D*) and DCE-MR (K(trans), K(ep), V(e), V(p)) parameters were significantly correlated (p<0.001). MATERIALS AND METHODS: 75 patients with newly diagnosed NPC were prospectively recruited. Diffusion-weighted MR and DCE-MR imaging were performed with respective IVIM (D, f, D*) and DCE (K(trans), K(ep), V(e), V(p)) MR parameters calculated. Patients were stratified into low and high tumor stage groups according to American Joint Committee on Cancer (AJCC) staging for determination of the predictive powers of IVIM-MR and DCE-MR parameters using t–test, ROC curve analyses and multiple logistic regression analysis. Correlation between IVIM-MR perfusion-related and DCE-MR parameters was assessed using Spearman's rank correlation. CONCLUSION: IVIM-MR perfusion-related and quantitative DCE-MR parameters were significantly correlated in the assessment of NPC and were both reliable independent predictors in the prediction of AJCC staging. IVIM-MR perfusion imaging can be a potential useful non-invasive perfusion imaging tool for clinical use in the assessment of NPC.