Presented at the Neonatal Society 2013 Autumn Meeting.
Chakkarapani E1,2, Poskitt KJ3, Miller SP4,5, Zwicker J3, Xu Q3, Wong D3, Hill A3, Roland E3, V Chau V4,5
1 School of Clinical Sciences, University of Bristol, UK
2 Neonatology, University of British Columbia & BC Women’s Hospital, Vancouver, Canada
3 Pediatrics (Neurology & Radiology), BC Children’s Hospital, Vancouver, Canada
4 University of Toronto, Ontario, Canada
5 Pediatric Neurology, Hospital for Sick Children, Toronto, Canada
Background: Therapeutic hypothermia following neonatal encephalopathy (NE) is associated with reductions in MRI brain lesions. This study aimed to determine the effect of TH on the evolution with time (predominant pattern and extent) of brain lesions on MRI.
Methods: Term infants with NE [non-cooled & cooled] born from 2004 to 2012 underwent brain MRI (DWI, T1 & T2) on day of life (DOL) 3-6 (MRI-I) and DOL 10-14 (MRI-II). Evolution of the extent and injury pattern of the basal ganglia (BG) and watershed (W) regions, and agreement between “MRI-I” and “MRI-II” were ascertained by a validated scoring system (1) and kappa (κ) statistic respectively. Cohort was classified to group A, if MRI-I occurred before DOL 3.5 and group B, if it occurred between DOL 3.5-6. UBCREC approved the study.
Results: Group A included 33 non-cooled and 13 cooled infants. Group B included 17 non-cooled and 26 cooled infants. Cooling was associated with less multifocal white matter lesions, normal watershed region and more normal MRIs (P<0.001). There was perfect agreement in the pattern of lesions between “MRI-I” and “MRI-II” in both non-cooled [group A(κ:0.92); group B(κ:1.0)] and cooled [group A(κ:0.81); group B(κ:0.94)] infants. All non-cooled [5/5(100%)] and [1/3(33%)] cooled infants with decreased extent of BG lesions on “MRI-II” had resolution of neuroimaging features of neonatal hypoglycaemia; [2/4 (50%)] non-cooled and [1/1 (100%)] cooled infants with worsening of extent of W lesion on “MRI-II” developed discrete white matter lesions. Cooling was significantly associated with worsening of extent of BG lesion, in particular to the perirolandic cortex, on “MRI-II” compared with non-cooled infants (9.3% versus 0%, p = 0.05).
Conclusion: In cooled infants with NE, the early MRI reliably estimated the pattern of brain lesion and extent of watershed lesions, but underestimated the extent of BG lesions missing the perirolandic cortex.
Corresponding author: ela.chakkarapani@bristol.ac.uk
References
1. Chau V. et al. Comparison of computer tomography and magnetic resonance imaging scans on the third day of life in term newborns with neonatal encephalopathy. Pediatrics 2009;123:319-326