Mechanisms of brain injury in the newborn

Abstract

Advances in obstetric and neonatal medical care have led to marked improvements in the chances of survival for extremely preterm and low birth weight babies. This review focuses on the mechanisms of neurological injury in extremely preterm and critically ill infants and discusses current progress in therapeutic strategies.

Severe Neonatal Anaemia, MRI Findings and Neurodevelopmental Outcome

“…In full-term infants, the deep grey matter nuclei are probably affected after an acute hypoxic-ischaemic insult due to changes in brain maturation and increased metabolic demands [1]. White matter injury is also found in full-term infants and is considered to be due to more prolonged and repetitive hypoxic-ischaemic events.…”

The Apparently Blind Infant

“…41,42,46,48,82,83,89,280,349,448,449,587 Some children with PVL are neurologically normal and function within the normal range at detailed neuropsychological and cognitive testing. 23,494,618 However, even premature infants with normal neurologic outcomes have a high incidence of neurocognitive impairment. 61,488,489 In addition to mild cognitive impairment, these children have a high prevalence of low-severity dysfunctions, including learning disabilities, borderline intellectual functioning, attention deficit/hyperactivity disorders, and specific neuropsychological deficits; behavioral problems reportedly occur in 50% to 70%.…”

“…37,76,366,521 Some patients with PVL show loss of volume within the corpus callosum, and some patients seem to develop new visual processing strategies that allow them to function normally. 514,618 This plasticity may reflect remodeling of existing gray-white matter regions, refinement and selection of dendritic connections, rerouting of white matter tracts to circumvent obstructions, and development of alternative cortical processing strategies. 618 Directed MR imaging studies in infants with white matter injury also show disturbances in cerebral growth, with a reduced volume of both gray and white matter.…”

“…514,618 This plasticity may reflect remodeling of existing gray-white matter regions, refinement and selection of dendritic connections, rerouting of white matter tracts to circumvent obstructions, and development of alternative cortical processing strategies. 618 Directed MR imaging studies in infants with white matter injury also show disturbances in cerebral growth, with a reduced volume of both gray and white matter. 275 An autopsy study of PVL patients showed gray matter lesions in a third or more of cases, with neuronal loss in the thalamus, globus pallidus, and cerebellar dentate nucleus, and gliosis in the deep gray nuclei (thalamus and basal ganglia) and basis pontis.…”

“…618 First, the arterial vascular supply to the immature brain leads to arterial end zones within the deep periventricular white matter. 31,32,35,36,38,91,145,280,281,349,575 Second, the autoregulatory mechanisms within the cerebral vasculature are immature.…”