Magnetic resonance imaging findings in a population-based cohort of children with cerebral palsy.

The purpose of this study was to investigate the frequency and spectrum of magnetic resonance imaging (MRI) abnormalities in a population of children with cerebral palsy (CP) who were born in the years 2000 and 2001 in Victoria, Australia. In 2000 and 2001, 221 children (126 males, 95 females; mean age 6y [SD 7mo], range 5-7y) with CP, excluding those with CP due to postneonatal causes (6% of all cases), were identified through the Victorian Cerebral Palsy Register. All medical records were systematically reviewed and all available brain imaging was comprehensively evaluated by a single senior MRI radiologist. MRI was available for 154 (70%) individuals and abnormalities were identified in 129 (84%). The study group comprised 88% with a spastic motor type CP; the distribution was hemiplegia in 33.5%, diplegia in 28.5%, and quadriplegia in 37.6% of children. Overall, pathological findings were most likely to be identified in children with spastic hemiplegia (92%) and spastic quadriplegia (84%). Abnormalities were less likely to be identified in non-spastic motor types (72%) and spastic diplegia (52%). The most common abnormalities identified on MRI were periventricular white matter injury (31%), focal ischaemic/haemorrhagic lesions (16%), diffuse encephalopathy (14%), and brain malformations (12%). Dual findings were seen in 3% of patients. This is the first study to document comprehensively the neuroimaging findings of all children identified with CP born over a consecutive 24-month period in a large geographical area.