In utero perfusing fraction maps in normal and growth restricted pregnancy measured using IVIM echo-planar MRI

Area of Science:

• Medical Imaging
• Obstetrics
• Physiology

Background:

• Placental blood flow is crucial for fetal development.
• Intrauterine growth restriction (IUGR) is associated with placental dysfunction.
• Non-invasive methods to assess placental perfusion are needed.

Purpose of the Study:

• To measure and visualize placental blood movement in vivo using IVIM MRI.
• To compare placental blood volume fraction (f) in normal and IUGR pregnancies.
• To investigate functional differences within the placenta.

Main Methods:

• IVIM MRI scans were performed on 13 normal and 7 IUGR pregnancies.
• A region of interest (ROI) was defined in the placenta.
• Moving blood volume (f) was calculated and mapped, comparing inner and outer placental zones.

Main Results:

• In normal pregnancies, (f(out)-f(in)) was generally positive (12/13 cases).
• In IUGR pregnancies, (f(out)-f(in)) was consistently negative (-4% ± 3).
• Perfusion fraction mapping revealed functional differences within normal placentas and between normal and IUGR placentas.

Conclusions:

• IVIM MRI effectively differentiates placental perfusion in normal versus IUGR pregnancies.
• The (f(out)-f(in)) parameter shows potential as a biomarker for placental health.
• This technique may aid in managing and investigating pregnancy compromise.