Apparent Diffusion Coefficient of the Placenta in Twin versus Singleton Pregnancies

Area of Science:

• Perinatal imaging
• Fetal MRI
• Diffusion-weighted imaging

Background:

• Previous studies on singleton pregnancies reported conflicting trends in apparent diffusion coefficient (ADC) values with gestational age (GA).
• Relative ADC (rADC) was found to be stable throughout pregnancy in singleton pregnancies.
• Understanding placental diffusion characteristics is crucial for assessing fetal well-being.

Purpose of the Study:

• To compare apparent diffusion coefficient (ADC) and relative ADC (rADC) values in placentas of twin and singleton pregnancies.
• To evaluate the influence of gestational age (GA) and plurality on placental diffusion characteristics.

Main Methods:

• Retrospective analysis of fetal MRI data from 11 twin and 23 singleton pregnancies.
• Placentas were analyzed for ADC and rADC values, with regions of interest in the placenta and fetal globe.
• Comparisons were made between different gestational ages and between singleton and twin placentas.

Main Results:

• No significant differences were observed in ADC or rADC values between singleton and twin placentas.
• ADC and rADC values remained stable across different gestational ages in both singleton and twin pregnancies.
• No significant differences were found when accounting for both GA and the number of fetuses.

Conclusions:

• The diffusion characteristics of placentas in twin pregnancies are comparable to those in singleton pregnancies.
• ADC and rADC values remain stable throughout pregnancy in both singleton and twin placentas.
• This stability suggests consistent extracellular water diffusion, despite placental maturation.