Placental MRI to monitor fetal health?

Placental MRI

Prenatal ultrasounds monitor fetal health in part by gauging blood flow from mother to fetus through the placenta. But researchers at MIT, Boston Children’s Hospital and Massachusetts General Hospital are diving deeper with magnetic resonance imaging. They’re taking advantage of MRI’s ability to measure oxygen concentrations in the placenta and fetal organs.

P. Ellen Grant, MD, who directs Boston Children’s Fetal-Neonatal Neuroimaging and Developmental Science Center, heads up the clinical arm of the project, part of the NIH-funded Human Placenta Project. Her group presented evidence last year that MRI measurements of oxygen absorption in the placenta correlated with intrauterine growth restriction, or a smaller-than-normal fetus. This spring, Grant’s team and their MIT colleagues proposed a method to map the timing of oxygen delivery in the placenta, showing that dysfunctional placentas delivered oxygen to the fetus in a more dispersed fashion.

Motion correction

Though MRI may well be too expensive for routine use in prenatal care, as a research tool it could shed more light on pregnancy risks and ways to improve fetal outcomes. But further progress requires overcoming a key hurdle: MRI normally requires subjects to lie completely still.

“We can ask mothers to breathe oxygen while they’re in the MRI scanner and see oxygen transport in the placenta,” Grant told Vector last year. “But the image analysis is complicated — the uterus moves, the mother moves and the placenta is squishy.”

Last week, Polina Golland’s group at MIT’s Computer Science and Artificial Intelligence Laboratory presented a paper demonstrating a new image interpretation algorithm that corrects for motion across time. Read more about their work on MIT’s website.