Abnormal brain microstructure and metabolism in small-for-gestational-age term fetuses with normal umbilical artery Doppler.
OBJECTIVE
To assess microstructural and metabolic brain differences between small-for-gestational age (SGA) and appropriate-for-gestational age (AGA) fetuses at 37 weeks' gestation by magnetic resonance imaging (MRI) spectroscopy and diffusion weighted imaging.


METHODS
Eight SGA and five matched AGA singleton fetuses, all with normal umbilical artery Doppler, were evaluated using MRI at 37 weeks to measure markers of brain microstructure and metabolism. The metabolic spectrum of N-acetyl-aspartate/choline, choline/creatine, inositol/choline and creatine/choline ratios in the left frontal lobe and the apparent diffusion coefficient from the right and left basal ganglia and frontal and occipital lobes, pyramidal tract and corpus callosum were analyzed and compared.


RESULTS
As compared with controls, SGA fetuses showed a significant increase in inositol/choline ratio (SGA, 0.57 vs. AGA, 0.25; P = 0.04) and significantly higher ADC values in the pyramidal tract (SGA, 119.87 x 10(-5) mm(2)/s vs. AGA, 105.11 x 10(-5) mm(2)/s; P = 0.04).


CONCLUSIONS
SGA fetuses with normal umbilical artery Doppler present microstructural and metabolic brain changes, suggesting the existence of an abnormal in-utero brain development in fetuses with this condition.
Sanz-Cortés
M
M
Maternal-Fetal Medicine Department, Institut Clinic de Ginecologia, Obstetricia i Neonatologia, Hospital Clínic, Barcelona, Spain.
Figueras
F
F
Bargalló
N
N
Padilla
N
N
Amat-Roldan
I
I
Gratacós
E
E
D000328:Adult; D001783:Blood Flow Velocity / Q000502:physiology; D001921:Brain / Q000098:blood supply* / Q000196:embryology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D005260:Female; D005317:Fetal Growth Retardation / Q000000981:diagnostic imaging / Q000503:physiopathology*; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age; D009483:Neuropsychological Tests; D011247:Pregnancy; D011597:Psychomotor Performance / Q000502:physiology*; D016216:Ultrasonography, Prenatal; D014469:Umbilical Arteries / Q000000981:diagnostic imaging / Q000196:embryology / Q000502:physiology*