Fractional anisotropy in white matter tracts of very-low-birth-weight infants.
BACKGROUND
Advances in neonatal intensive care have not yet reduced the high incidence of neurodevelopmental disability among very-low-birth-weight (VLBW) infants. As neurological deficits are related to white-matter injury, early detection is important. Diffusion tensor imaging (DTI) could be an excellent tool for assessment of white-matter injury.


OBJECTIVE
To provide DTI fractional anisotropy (FA) reference values for white-matter tracts of VLBW infants for clinical use.


METHODS
We retrospectively analysed DTI images of 28 VLBW infants (26-32 weeks gestational age) without evidence of white-matter abnormalities on conventional MRI sequences, and normal developmental outcome (assessed at age 1-3 years). For DTI an echoplanar sequence with diffusion gradient (b = 1,000 s/mm(2)) applied in 25 non-collinear directions was used. We measured FA and apparent diffusion coefficient (ADC) of different white-matter tracts in the first 4 days of life.


RESULTS
A statistically significant correlation was found between gestational age and FA of the posterior limb of the internal capsule in VLBW infants (r = 0.495, P<0.01).


CONCLUSIONS
Values of FA and ADC were measured in white-matter tracts of VLBW infants. FA of the pyramidal tracts measured in the first few days after birth is related to gestational age.
Dudink
Jeroen
J
Division of Neonatology, Department of Paediatrics, Erasmus MC-Sophia Children's Hospital, Rotterdam, The Netherlands. j.dudink@erasmusmc.nl
Lequin
Maarten
M
van Pul
Carola
C
Buijs
Jan
J
Conneman
Nikk
N
van Goudoever
Johannes
J
Govaert
Paul
P
D000704:Analysis of Variance; D016880:Anisotropy; D001921:Brain / Q000196:embryology*; D001931:Brain Mapping / Q000379:methods*; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D019102:Infant, Very Low Birth Weight; D008297:Male; D009413:Nerve Fibers, Myelinated / Q000648:ultrastructure*; D012016:Reference Values; D012189:Retrospective Studies