MRI-Based Placental Perfusion Assessment in Intrauterine Growth Restriction: Advances and Emerging Biomarkers

Intrauterine growth restriction (IUGR) is a complex obstetric condition characterized by impaired foetal growth due to placental insufficiency, and it remains a leading contributor to perinatal morbidity and mortality worldwide. Early and accurate detection of placental dysfunction is essential to improve outcomes; however, conventional diagnostic methods such as Doppler ultrasound provide only indirect assessments of placental health. In recent years, advanced magnetic resonance imaging (MRI) techniques have emerged as powerful, non-invasive tools to evaluate placental perfusion and function more directly. This review highlights the current state of MRI-based placental perfusion imaging in the context of suspected IUGR, with a focus on key modalities including arterial spin labeling (ASL), dynamic contrast-enhanced (DCE) MRI, intravoxel incoherent motion (IVIM), and blood oxygen level-dependent (BOLD) imaging. These techniques allow for the quantification of critical physiological parameters such as tissue blood flow, microvascular density, and oxygenation. Additionally, we discuss recent clinical studies that validate emerging imaging biomarkers—such as perfusion fraction, ΔT2* response, and K trans—as potential tools for diagnosis, risk stratification, and monitoring of IUGR. Despite challenges such as motion artifacts and the need for standardization, MRI-based placental assessment holds significant promise for improving clinical decision-making and individualized care in high-risk pregnancies. This review aims to consolidate current evidence, identify gaps in the literature, and propose directions for future research in the field of functional placental imaging.