HYPOXIC-ISCHEMIC ENCEPHALOPATHY IN AREAS OF PRIMARY MYELINATION - A NEUROIMAGING AND PET STUDY

The stage of regional structural and biochemical development of the ce ntral nervous system appears as a critical factor determining the dist ribution of hypoxic-ischemia lesions during the perinatal period. We d escribe the brain lesions in 12 patients who suffered hypoxia-ischemia during the perinatal period. The gestational age ranged from 35 to 42 weeks and the age at death from 2 to 16 weeks. There is one patient a live at age 18 years and a second patient at age 1 year. The cerebral cortical damage is mainly restricted to areas of primary myelination a nd adjacent subcortical white matter, In addition, there is thalamic, basal ganglia, brainstem, and spinal cord damage, It is postulated tha t selective damage occurs in those areas which at the moment of the hy poxic-ischemic insult had achieved higher rates of oxygen-glucose util ization. This hypothesis is supported by studies utilizing positron em ission tomography which indicates that glucose utilization in the norm al human neonatal brain follows a phylogenetic order, Regions that ach ieved higher levels of glucose consumption are those that suffered the brunt of the damage in our term neonates.