Article

The aim of this study was to determine the feasibility of undertaking visual
functional magnetic resonance imaging (fMRI) in very preterm children. METHOD:
Forty-seven infants born at less than 32 weeks gestational age (25 males, 22
females; mean (SD) age at birth 28.8 wks [1.9]) were scanned using 1.5 T MRI as
part of a longitudinal neuroimaging study. These infants were scanned at preterm
age (within 2 wks of birth) and at term-equivalent age. Quantitative T2* data and
fMRI in response to visual stimuli (flashing strobe) were acquired in this
population. T2* values were compared at preterm age and at term-equivalent age
using a two-tailed t-test. A general linear model was used to evaluate occipital
lobe response to visual stimuli. RESULTS: T2* values were significantly higher at
preterm age than at term-equivalent age in both the medial and lateral occipital
lobes (preterm infants: 187.2 ms and 198.4 ms respectively; term infants: 110.9
ms and 133.2 ms respectively; p<0.002). Significant positive occipital lobe
activation (q<0.01) was found in 3 out of 65 (5%) fMRIs carried out at preterm
age and in 19 out of 26 (73%) scans carried out at term-equivalent age.
INTERPRETATION: Visual stimuli do not elicit a reliable blood oxygen
level-dependent (BOLD) response in very preterm infants during the preterm
period. This suggests that BOLD fMRI may not be the appropriate modality for
investigating occipital lobe function in very preterm infants.
CI - (c) The Authors. Developmental Medicine & Child Neurology (c) 2012 Mac Keith
Press.

Langue : ANGLAIS