Article

Patterns of injury in term-born infants with neonatal encephalopathy
following hypoxia-ischaemia are seen earlier and are more conspicuous on
diffusion-weighted magnetic resonance imaging (DW-MRI) than on conventional
imaging. Although the prognostic value of DW-MRI in infants with basal ganglia
and thalamic damage has been established, data in infants in whom there is
extensive injury in a watershed distribution are limited. The aim of this study
was to assess cognitive and functional motor outcome in a cohort of infants with
changes in a predominantly watershed distribution injury on neonatal cerebral
MRI, including DWI. METHOD: DW-MRI findings in infants with neonatal
encephalopathy following hypoxia-ischaemia were evaluated retrospectively.
Twenty-two infants in whom DWI changes exhibited a predominantly watershed
distribution were enrolled in the study (10 males, 12 females; mean birthweight
3337 g, 2830-3900 g; mean gestational age 40.5 wks, 37.9-42.1 wks). Follow-up MRI
data at the age of 3 months (n=15) and over the age of 18 months (n=7) were
analysed. In survivors, neurodevelopmental outcome was assessed with the
Griffiths Mental Development Scales at the age of at least 18 months.
Amplitude-integrated electroencephalography was used to score background patterns
and the occurrence of epileptiform activity. RESULTS: DW-MRI revealed
abnormalities that were bilateral in all infants and symmetrical in 10. The
posterior regions were more severely affected in five infants and the anterior
regions in three. Watershed injury occurred in isolation in 10 out of 22 infants
and was associated with involvement of the basal ganglia and thalami in the other
12, of whom seven died. Cystic evolution, seen on MRI at age 3 months, occurred
in three of the 15 surviving infants. Neurodevelopmental assessment of the
surviving infants was performed at a median age of 35 months (range 18-48 mo). Of
the five survivors with basal ganglia and thalamic involvement, two developed
cerebral palsy, one had a developmental quotient of less than 85, and two had a
normal outcome. Of the 10 infants with isolated watershed injury, nine had an
early normal motor and cognitive outcome. In all infants with a favourable
outcome, background recovery was seen on amplitude integrated EEG within 48 hours
after birth. CONCLUSION: Extensive DWI changes in a watershed distribution in
term-born neonates are not invariably associated with adverse sequelae, even in
the presence of cystic evolution. Associated lesions of the basal ganglia and
thalami are a better predictor of adverse sequelae than the extent and severity
of the watershed abnormalities seen on DW-MRI.
CI - (c) The Authors. Developmental Medicine & Child Neurology (c) 2013 Mac Keith
Press.

Langue : ANGLAIS