Globally, substance use disorders contribute a significant proportion of the burden of disease in low, middle, and high-income countries. South Africa has a high prevalence of alcohol use disorders and foetal alcohol syndrome. Neuroimaging studies of prenatal alcohol exposure have reported differences in structure and metabolism of many brain circuits, but little has been reported on the impact in infancy. Diffusion tensor imaging (DTI) has proved to be a useful tool for investigating white matter tracts, but has not been studied in infants with prenatal alcohol exposure.

Methods:Infants aged 2-4 weeks were imaged using DTI sequences on a Siemens Magnetom 3T system. Eleven healthy unexposed infants (mean age: 22.3 days SD 7.2; 7 males, 4 females) and 20 alcohol exposed infants (mean age: 20.2 days SD 4.5; 11 males, 9 females) were included in this preliminary tract-based spatial statistics (TBSS) analysis.

Results:When comparing fractional anisotropy between alcohol-exposed and healthy infants, significant decreases (p < 0.05) were found for the following white matter regions: inferior cerebellar peduncle, fornix, corona radiata, cingulum, cerebral peduncle, internal capsule.

Conclusion:These results indicate that even in newborns the neurobiological effects of prenatal alcohol exposure are observable, with reduced white matter integrity. This has not been previously reported in infants when confounding post-natal environmental influences on children from these backgrounds have not yet come into play. The location of the findings is consistent with previously reported studies of white matter tracts  in older children with foetal alcohol syndrome.