Value of placental virtual magnetic resonance elastography and intravoxel incoherent motion-based diffusion and perfusion in predicting adverse outcomes of small-for-gestational-age infants

Abstract

Abstract Objective It is critical to early monitor and manage small-for-gestational age (SGA) infants with truly adverse outcomes not detected by conventional methods. We aimed to explore the value of diffusion-weighted imaging (DWI)-based virtual magnetic resonance elastography (vMRE) and intravoxel incoherent motion (IVIM)-based biexponential and stretched exponential parameters in predicting adverse outcomes of SGA infants. Methods Twenty SGA infants with adverse outcomes and forty without adverse outcomes were included in this prospective study. One DWI-based vMRE parameter [the stiffness value (μ diff)], five IVIM–based parameters [true diffusion coefficient (D), pseudo-diffusion coefficient (D * ), perfusion fraction (f), diffusion distribution coefficient (DDC), and diffusion heterogeneity index (Alpha)] and apparent diffusion coefficient (ADC) were calculated and compared between groups. The predictive efficiency was compared by the logistic regression analysis and receiver operating characteristic curve analysis. The relationship between the μ diff value with gestational age was also evaluated. Results The placental μ diff value was remarkably higher, and the f, DDC, and ADC values were considerably lower in the SGA infants with adverse outcomes compared with those without adverse outcomes. The μ diff and f value were predictive risk factors for SGA infants with adverse outcomes. A combined predictive model (μ diff and f) improved the predictive efficacy. Moreover, there was no statistically significant correlation between the placental stiffness value and gestational age. Conclusions Functional MRI parameters to quantify placenta elastography and microcirculation in SGA patients. This might be a useful tool to assess placental function and a vital non-invasive supplement for predicting adverse outcomes of SGA infants. Critical relevance statement This prospective study shows DWI-based virtual magnetic resonance elastography and intravoxel incoherent motion-based functional parameters to quantify placenta elastography and microcirculation in small-for-gestational-age patients, which could complement existing non-invasive methods for monitoring and predicting neonatal perinatal adverse outcome. Key points • vMRE is an emerging non-invasive imaging technique for evaluating placenta stiffness. • SGA infants with adverse outcome have stiffer placental elasticity and lower microcirculation. • Risk factors combination displayed better efficacy in predicting adverse outcomes of SGA. Graphical Abstract

Keywords

• Intravoxel incoherent motion
• Placenta
• Small-for-gestational-age infants
• Virtual magnetic resonance elastography