DTI of Opioid-Exposed Fetuses Using ComBat Harmonization: A Bi-Institutional Study

Area of Science:

• Neuroimaging
• Developmental Neuroscience
• Prenatal Health

Background:

• Mechanisms behind cognitive, behavioral, and vision deficits in children exposed to opioids prenatally remain unclear.
• Existing research suggests white matter (WM) alterations in infants and children with prenatal opioid exposure, but the timeline of these changes is unknown.

Purpose of the Study:

• To investigate differences in brain diffusion tensor imaging (DTI) MRI parameters between fetuses exposed to opioids and healthy controls.
• To evaluate potential early microstructural changes in the fetal brain due to prenatal opioid exposure.

Main Methods:

• A pilot, prospective cohort study involving third-trimester pregnant subjects.
• Fetal DTI of the brain was performed using 20 noncolinear diffusion directions and a b-value of 500 s/mm² at 2.5-mm isotropic resolution.

Main Results:

• The study included 26 fetuses (11 opioid-exposed, 15 controls).
• After adjusting for gestational age, opioid-exposed fetuses showed significantly higher fractional anisotropy values in 8 specific WM tracts compared to controls.
• Additional DTI indices indicated significant alterations in various brain regions.

Conclusions:

• The findings provide preliminary evidence of cerebral WM microstructural differences in fetuses exposed to opioids.
• Larger population studies are necessary to fully elucidate these microstructural changes and their long-term implications.