[Show abstract][Hide abstract] ABSTRACT: The corpus callosum (CC) is a cerebral structure that reflects cognitive status in several neurological pathologies. Visual inspection of MRI has shown that hypoxic-ischemic encephalopathy(HIE) causes callosal damage.
To quantify the CC surface in a sample of patients with antecedents of HIE and a group of matched controls.
Comparisons of CC measures among control subjects, mild HIE patients and moderateHIE patients as well as correlates of CC surface and neuropsychological performance.
Twenty-one adolescent patients with childhood antecedents of HIE were compared to 21 controls. ANALYZE software was used to semi-automatically measure the CC area.
Patients with moderate HIE showed corpus callosum reduction. The isthmus and genus were the most affected regions. Corpus callosum size correlated with cognitive function.
Corpus callosum quantification provides new evidence of subtle residual deficits in subjects with HIE antecedents without apparent neurological sequelae.
[Show abstract][Hide abstract] ABSTRACT: Previous studies have shown the hippocampus and basal ganglia to be highly sensitive to hypoxic-ischemic insult. The authors' aim was to evaluate the long-term effects of perinatal asphyxia (PA) on the hippocampus and caudate nucleus in a group of participants born at term and who met the criteria for hypoxic-ischemic encephalopathy (HIE). Additionally, the authors looked for damage in other brain regions using voxel-based morphometry (VBM).
The sample consisted of 13 participants (8 boys and 5 girls) with a mean age at study of 16.23 years (+/- 2.89) with antecedents of perinatal asphyxia, diagnosed as moderate hypoxic-ischemic encephalopathy. A group of 13 healthy adolescents matched for age, sex, educational level, and social background were recruited as a comparison group. MR scans were acquired on a 1.5T Signa (General Electric, Milwaukee, WI) to evaluate hippocampal and caudate volumes and to perform VBM analysis. Finally, Rey's Auditory Verbal Learning Test was administered to evaluate verbal long-term memory.
HIE participants were found to have bilateral hippocampal atrophy (P = .015) and gray matter damage in temporal and frontal lobes. The caudate nucleus showed no atrophic changes in PA participants, and VBM analysis did not reveal other consistent brain abnormalities. Verbal long-term memory was slightly worse in HIE participants.
These findings indicate that PA produces hippocampal and other nonspecific long-term damage, which cannot be compensated for by plasticity mechanisms. However, this damage does not preclude normal development and scholarship.
No preview · Article · Feb 2003 · Journal of Neuroimaging
[Show abstract][Hide abstract] ABSTRACT: To investigate the long-term neuropsychological consequences of perinatal asphyxia (PA).
A group of adolescents were assessed with antecedents of mild (n = 8) and moderate (n = 20) PA, and a matched group of 28 healthy adolescents as a control group. Neuropsychological assessment included tests of memory, perceptual-motor skills, and frontal lobe functions, because these are areas of cognitive functioning susceptible to hypoxic conditions.
Subjects with moderate PA showed significant differences from the control group on tests related to delayed recall for both verbal and visual information, perceptual-motor speed, and tests assessing attention and executive functions. Conversely, subjects in the mild PA group exhibited scores which were similar to those of the control group in all the assessed variables.
The present findings demonstrate that subtle but persistent neuropsychological deficits were observed in adolescents with antecedents of moderate PA, but not in those classified with mild asphyxia.
[Show abstract][Hide abstract] ABSTRACT: Neuropathological studies of the cerebral consequences of perinatal asphyxia have shown the hippocampal and basal ganglia to be particularly vulnerable to injury. It has been suggested that neuroanatomical lesions of this kind may produce declarative and procedural memory deficits. To test this hypothesis we compared memory performance in 28 adolescents with antecedents of perinatal asphyxia and 28 controls matched for age, sex and sociocultural status. Results showed impairment in verbal and visual declarative memory in subjects with antecedents of moderate neonatal encephalopathy but not in subjects with mild encephalopathy. Procedural memory performance was similar in all groups. The results suggest that the hippocampal system is more vulnerable to perinatal asphyxia than the striatal system.
[Show abstract][Hide abstract] ABSTRACT: The authors performed neuropsychological and (1)H-MRS studies in 18 subclinical patients with antecedents of perinatal asphyxia (PA) and in 18 matched control subjects. Patients with PA showed reduced values of N-acetylaspartate (NAA) in both the basal ganglia and the midtemporal region (MTR) and reduced NAA/choline values in the MTR. Neuropsychological testing showed group differences in tasks related to attention and memory. These results indicate persistent dysfunctions in cerebral structures vulnerable to hypoxia and demonstrate the utility of MRS for the long-term evaluation of cerebral sequelae of neonatal asphyxia.
[Show abstract][Hide abstract] ABSTRACT: Los estudios neuropatológicos sobre asfixia perinatal han puesto de manifiesto una alta vulnerabilidad a las lesiones en el hipocampo y los ganglios basales. Esta afectación anatómica puede corresponderse a una alteración de la memoria declarativa y procedimental respectivamente. De acuerdo con esta hipótesis comparamos el rendimiento de diversas tareas de memoria en una muestra de 28 adolescentes con antecedentes de asfixia perinatal y 28 controles emparejados por edad, sexo y nivel sociocultural. Los resultados mostraron una alteración de la memoria declarativa verbal y visual en los sujetos con encefalopatía moderada, pero no en los leves. Sin embargo, no observamos diferencias significativas entre grupos en las tareas de aprendizaje procedimental. Los resultados sugieren una mayor vulnerabilidad del sistema hipocampal respecto al estriatal en la asfixia perinatal.