Microstructural brain development after perinatal cerebral white matter injury assessed by diffusion tensor magnetic resonance imaging

Citation
Ps. Huppi et al., Microstructural brain development after perinatal cerebral white matter injury assessed by diffusion tensor magnetic resonance imaging, PEDIATRICS, 107(3), 2001, pp. 455-460
Citations number
20
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Pediatrics,"Medical Research General Topics
Journal title
PEDIATRICS
ISSN journal
0031-4005 → ACNP
Volume
107
Issue
3
Year of publication
2001
Pages
455 - 460
Database
ISI
SICI code
0031-4005(200103)107:3<455:MBDAPC>2.0.ZU;2-J
Abstract
Objective. Brain injury in premature infants is characterized predominantly by perinatally acquired lesions in the cerebral white matter (WM). The imp act of such injury on the subsequent development of cerebral WM is not clea r. This study uses diffusion tensor magnetic resonance imaging (MRI) to eva luate the effects of cerebral WM injury on subsequent microstructural brain development in different WM areas of the brain. Methods. Twenty premature infants (gestational age: 29.1 +/- 1.9 weeks) wer e studied by conventional MRI within the first 3 weeks of life and again at term, with the addition at the latter time of diffusion tensor MRI. Ten of the preterm infants had cerebral WM injury identified by the early MRI and were matched with 10 premature infants of similar gestational age and neon atal course but with normal neonatal MRI scans. Diffusion tensor MRI at ter m was acquired in coronal and axial planes and used to determine the appare nt diffusion coefficient, a measure of overall restriction to water diffusi on, and the relative anisotropy (RA), a measure of preferred directionality of diffusion, in central WM, anterior frontal WM, occipital WM, temporal W M, and the posterior limb of the internal capsule. Diffusion vector maps we re generated from the diffusion tensor analysis to define the microstructur al architecture of the cerebral WM regions. Results. At term, the diffusion tensor MRI revealed no difference in appare nt diffusion coefficient among preterm infants with or without perinatal WM lesions. By contrast, RA, the measure of preferred directionality of diffu sion and thereby dependent on development of axonal fibers and oligodendrog lia, was 25% lower in central WM, the principal site of the original WM inj ury. However, RA was unaffected in relatively uninjured WM areas, such as t emporal, anterior frontal, and occipital regions. Notably, RA values in the internal capsule, which contains fibers that descend from the injured cere bral WM, were 20% lower in the infants with WM injury versus those without. Diffusion vector maps showed striking alterations in the size, orientation , and organization of fiber tracts in central WM and in those descending to the internal capsule. Conclusions. Perinatal cerebral WM injury seems to have major deleterious e ffects on subsequent development of fiber tracts both in the cerebral WM an d more distally. The ultimate impact of brain injury in the newborn should be considered as a function not only of tissue destruction, but also of imp aired subsequent brain development.