Foetal volumetry using magnetic resonance imaging in intrauterine growth restriction

Objectives: We used magnetic resonance imaging (MRI) to perform volumetry of foetuses with and without growth restriction, and identify deviations in organ growth.

Study design: 20 growth restricted and 19 normal foetuses were scanned once during pregnancy at gestational age 20.53-36.57 weeks. MRI scans were performed on a 1.5T system using ssFSE sequences. Manual segmentation of whole body, brain, heart, lung, liver, thymus and kidney volume was performed. Data on the severity of foetal growth restriction and pregnancy outcome was collected.

Results: There was a significant reduction in foetal whole body volume and volume of all internal organs except the brain in growth restricted foetuses. A brain:liver ratio above 3.0 was associated with a 3.3 fold increase in risk of perinatal mortality (95% CI=1.68-6.47).

Conclusion: MRI provides an accurate assessment of foetal organ growth. It may have a role to play in monitoring disease severity and the effect of future interventions.