The MRI in 22 children with athetotic cerebral palsy was studied in the Department of Pediatric Neurology, Seirei-Mikatabara General Hospital, Hamamatsu, the Department of Pediatrics, National Rehabilitation Center for Disabled Children, Tokyo, and the Department of Pediatrics, Nagoya City University Medical School, Japan. Perinatal asphyxia had been diagnosed in 16, neonatal jaundice in 2, and no predisposing condition in 4. MRI lesions possibly caused by asphyxia were found in the basal ganglia, thalamus, and/or cerebral white matter in 14 of 16 children. No abnormalities were seen in the cerebral cortex of the subjects. Six children with lesions in both the thalamus and putamen had moderate or severe motor abnormality. Children with lesions in the cerebral white matter only had mild motor abnormality. 
COMMENT. Brain lesions causing athetosis in CP children may not be revealed by CT scan but high intensity areas in the thalamus, putamen and/or cerebral white matter may be demonstrated in T2-weighted images of the MRI. The evidence of perinatal asphyxia in 16 of the 22 children reported was judged by Apgar scores of 3 and below, generalized hypotonia, and convulsions in the neonatal period. The MR imaging was performed at 2-12 years of age and studies obtained soon after birth might have documented a prenatal timing for the lesions.