Can functional MRI help differentiate invasive placentas in patients with placenta previa?

Introduction: To investigate if functional MRI can add additional diagnostic value in distinguishing invasive placentas in patients with placenta previa. Methods: A total of 53 patients with invasive placentas and 20 patients with noninvasive placentas were retrospectively enrolled. DWI parameters were measured by volumetric analysis and MRI images were reviewed,respectively. The differences of DWI parameters and MRI features were compared. The receiver operating characteristic (ROC) curve and logistic regression analysis were used to assess the ability of different diffusion parameters and MRI features for distinguishing invasive placentas. Results: Comparisons between patients with invasive and noninvasive placentas demonstrated D mean and D* min were significantly higher while ADC max and D max were significantly lower in patients with invasive placentas (p < 0.05). T2 dark bands, placental heterogeneity, abnormal intraplacental vascularity and placental bulge were associated with invasive placentas (p < 0.05). Multivariate analysis demonstrated that D max was an independent risk factor for invasive placentas. The AUC was 0.79 with sensitivity, specificity, and accuracy of 70%, 87%, and 78.5%, respectively. Discussion: D max helps distinguish invasive placentas in patients with placenta previa.