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Chapter 49 - The role of diffusion- and perfusion-weighted brain imaging in neonatology

from Section 8 - Pediatrics

Published online by Cambridge University Press:  05 March 2013

By
Mary A. Rutherford  and
Serena J. Counsell
Edited by
Jonathan H. Gillard ,
Adam D. Waldman  and
Peter B. Barker
Jonathan H. Gillard
Affiliation:
University of Cambridge
Adam D. Waldman
Affiliation:
Imperial College London
Peter B. Barker
Affiliation:
The Johns Hopkins University School of Medicine
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Summary

Introduction

MR imaging (MRI) of the neonatal brain is a relatively new field but there are now many publications that illustrate its role in defining malformations, establishing patterns of perinatal injury, and predicting outcome.[1–7]

Detailed information about the pattern of lesions following perinatal brain injury can be obtained with MRI,[1,2,6,8] and it is an excellent predictor of outcome in infants with hypoxic–ischemic encephalopathy (HIE).[4,7,9–11] Conventional MRI has also been used to study perinatal stroke; later hemiplegia develops if there is involvement of three sites; hemispheric white matter (WM), basal ganglia and thalami (BGT), and posterior limb of the internal capsule (PLIC).[8] In preterm infants with unilateral focal lesions, the development of a hemiplegia is related to the MR signal intensity within the ipsilateral PLIC at term equivalent age.[12] Diffusion-weighted imaging (DWI) may also help in predicting outcome by detecting abnormal signal intensities in the corticospinal tracts that precede the development of Wallerian degeneration.[12] While perfusion-weighted imaging (PWI) may have many applications in studies of the immature brain, there are very few published studies using PWI in neonates either with contrast-enhanced [13–16] or arterial spin labeling (ASL) techniques.[17]

Type
Chapter
Information
Clinical MR Neuroimaging
Physiological and Functional Techniques
 , pp. 750 - 765
Publisher: Cambridge University Press
Print publication year: 2009

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References

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