Brain Proton Magnetic Resonance Spectroscopy and Imaging in Children Exposed to Cocaine in Utero

Abstract

Objective. The effects of prenatal cocaine exposure have been examined using neurobehavioral and brain structural evaluations; however, no study has examined the effects of prenatal cocaine on brain metabolism. Proton magnetic resonance spectroscopy (1H-MRS) is a noninvasive method to examine the biochemistry of various brain regions. The purpose of this study was to examine the possible neurotoxic effects of prenatal cocaine exposure on the developing brain using 1H-MRS. Methods. Cocaine-exposed children (n = 14) and age-matched unexposed control participants (n = 12) were evaluated with MRI and localized1H-MRS. Metabolite concentrations ofN-acetyl-containing compounds (NA), total creatine (Cr), choline-containing compounds, myoinositol, and glutamate + glutamine were measured in the frontal white matter and striatum. Results. Despite an absence of structural abnormalities in either group, children exposed to cocaine in utero had significantly higher Cr (+13%) in the frontal white matter. NA, primarily a measure of N-acetyl aspartate and neuronal content, was normal in both regions examined by 1H-MRS. Normal NA suggests no significant neuronal loss or damage in the 2 brain regions examined in children exposed to cocaine prenatally. Conclusions. Consistent with findings in abstinent adult cocaine users, we found increased Cr in the frontal white matter, with normal NA in children exposed to cocaine. These findings suggest the need to investigate further possible abnormalities of energy metabolism in the brain of children exposed to cocaine in utero. In addition, this study demonstrates the feasibility of using 1H-MRS to investigate the effects of prenatal drug exposure on the developing brain.