Abstract
Background
Neonatal encephalopathy (NE) is a clinically defined neurological syndrome commonly caused by ischemia.
Objective
We investigated white matter integrity in children with NE using diffusion tensor imaging (DTI) and examined the hypothesis that white matter insults not visible on conventional MRI may have abnormal fractional anisotropy (FA) on DTI.
Materials and methods
DTI was performed on 36 term encephalopathic neonates who had hypothermia therapy. Of these, 12 neonates had normal conventional MRI findings (NNE) and 24 neonates had abnormal MRI findings (ANE). Twelve term-equivalent premature neonates with normal clinical neuroimaging and neurological function served as the control group.
Results
We found significant reductions in measured FA in white matter in the ANE neonates compared to the control group. There were, however, no significant differences in measured FA in white matter between the NNE and the control group.
Conclusion
We did not find white matter changes detectable by DTI in encephalopathic neonates post hypothermia with normal conventional MRI findings. Further studies would be required to determine whether this unexpected finding is a direct result of neuroprotective effects of hypothermia, or more sophisticated measures of FA are required to detect subtle white matter injury.
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References
(2003) Neonatal encephalopathy and cerebral palsy: defining the pathogenesis and patho- physiology. American College of Obstetricians and Gynecologists, Washington DC
Kuenzle C, Baenziger O, Martin E et al (1994) Prognostic value of early MR imaging in term infants with severe perinatal asphyxia. Neuropediatrics 25:191–200
Belet N, Belet U, Incesu L et al (2004) Hypoxic-ischemic encephalopathy: correlation of serial MRI and outcome. Pediatr Neurol 31:267–274
Boichot C, Walker PM, Durand C et al (2006) Term neonate prognoses after perinatal asphyxia: contributions of MR imaging, MR spectroscopy, relaxation times, and apparent diffusion coefficients. Radiology 239:839–848
Barkovich AJ, Raybaud C (2012) Patterns of diffuse hypoxic-ischemic brain injury. In: Pediatric neuroimaging, 5th edn. Wolters Kluwer Health/Lippincott Williams & Wilkins, Philadelphia, pp 291–307
Barkovich A, Miller SP, Bartha A et al (2006) MR imaging, MR spectroscopy, and diffusion tensor imaging of sequential studies in neonates with encephalopathy. AJNR Am J Neuroradiol 27:533–547
Shankaran S, Laptook A, Ehrenkranz R et al (2005) Whole body hypothermia for neonates with hypoxic-ischemic encephalopathy. N Engl J Med 353:1574–1584
Woodward LJ, Anderson PJ, Austin NC et al (2006) Neonatal MRI to predict neurodevelopmental outcomes in preterm infants. N Engl J Med 355:685–694
Robertson CM, Finer NN (1993) Long-term follow-up of term neonates with perinatal asphyxia. Clin Perinatol 20:438–500
Beaulieu C (2002) The basis of anisotropic water diffusion in the nervous system—a technical review. NMR Biomed 15:434–455
Ward P, Counsell S, Allsop J et al (2006) Reduced fractional anisotropy on diffusion tensor magnetic resonance imaging after hypoxic-ischemic encephalopathy. Pediatrics 117:e619–e630
Barkovich A, Westmark K, Partridge C et al (1995) Perinatal asphyxia: MR findings in the first 10 days. AJNR Am J Neuroradiol 16:427–438
Vos SB, Jones DK, Jeruissen B et al (2012) The influence of complex white matter architecture on the mean diffusivity in diffusion tensor MRI of the human brain. Neuroimage 59:2208–2216
Rutherford M, Ramenghi LA, Edwards AD et al (2010) Assessment of brain tissue injury after moderate hypothermia in neonates with hypoxic-ischaemic encephalopathy: a nested substudy of a randomised controlled trial. Lancet Neurol 9:39–45
Righini A, Doneda C, Parazzini C et al (2010) Diffusion tensor imaging of early changes in corpus callosum after cerebral hemisphere lesions in newborns. Neuroradiology 52:1025–1035
Groenendaal F, Benders M, Vries L (2006) Pre-Wallerian degeneration in the neonatal brain following perinatal cerebral hypoxic-ischemia demonstrated with MRI. Semin Perinatol 30:146–150
Bednarek N, Mathur A, Inder T et al (2012) Impact of therapeutic hypothermia on MRI diffusion changes in neonatal encephalopathy. Neurology 78:1420–1427
Young PA, Young PH, Tolbert DL (1997) The basal ganglia. In: Basic clinical neuroanatomy, 1st edn. Lippincott Williams & Wilkins, Philadelphia, pp 83–89
Bonifacio S, Glass H, Chau V et al (2010) Extreme premature birth is not associated with impaired development of brain microstructure. J Pediatr 157:726–732
Lepomaki V, Paavilainen T, Matomaki J et al (2012) Effect of antenatal growth and preaturity on brain matter: diffusion tensor study. Pediatr Radiol 42:692–698
Oken E, Kleinman KP, Rich-Edwards J et al (2003) A nearly continuous measure of birth weight for gestational age using a United States national reference. BMC Pediatr 3:6
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Lee, E.C.C., Kwatra, N.S., Vezina, G. et al. White matter integrity on fractional anisotropy maps in encephalopathic neonates post hypothermia therapy with normal-appearing MR imaging. Pediatr Radiol 43, 709–715 (2013). https://doi.org/10.1007/s00247-012-2572-2
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DOI: https://doi.org/10.1007/s00247-012-2572-2