In vivo assessment of placental microstructure in normal pregnancy and gestational hypertension: An IVIM-based MRI study

OBJECTIVE: Our aim was to evaluate placental function using IVIM diffusion-weighted MRI in both normal pregnancies and gestational hypertension, and develop a combined predictive model for severe fetal growth restriction (sFGR). METHOD: We studied 32 healthy pregnant women and 40 with gestational hypertension (20 with sFGR, 20 without). Five IVIM-based parameters were calculated: perfusion fraction (f), true diffusion coefficient (D), pseudo-diffusion coefficient (D∗), diffusion distribution coefficient (DDC), and superdiffusion index (γ). These parameters were compared between the groups. Predictive efficiency was evaluated using logistic regression analysis and receiver operating characteristic (ROC) curve analysis. RESULTS: Compared to controls, gestational hypertension cases exhibited lower f, D, DDC values and higher γ value (all p < 0.05). Both f value (OR: 0.257, 95 % CI: 0.069-0.957; p = 0.043) and γ value (OR: 0.343, 95 % CI: 0.128-0.918; p = 0.033) independently predicted sFGR. A combined predictive model (f, D∗, DDC and γ) achieved superior prediction (AUC: 0.838). CONCLUSION: IVIM-derived parameters effectively quantify placental microcirculation differences and show strong potential as non-invasive biomarkers for sFGR prediction in gestational hypertension.