RESUMEN
The brain has a remarkable capacity for reorganization following injury, especially during the first years of life. Knowledge of structural reorganization and its consequences following perinatal injury is sparse. Here we studied changes in brain tissue volume, morphology, perfusion, and integrity in children with hemiplegia compared to typically developing children, using MRI. Children with hemiplegia demonstrated reduced total cerebral volume, with increased cerebrospinal fluid (CSF) and reduced total white matter volumes, with no differences in total gray matter volume, compared to typically developing children. An increase in cortical thickness at the hemisphere contralateral to the lesion (CLH) was detected in motor and language areas, which may reflect compensation for the gray matter loss in the lesion area or retention of ipsilateral pathways. In addition, reduced cortical thickness, perfusion, and surface area were detected in limbic areas. Increased CSF volume and precentral cortical thickness and reduced white matter volume were correlated with worse motor performance. Brain reorganization of the gray matter within the CLH, while not necessarily indicating better outcome, is suggested as a response to neuronal deficits following injury early in life.
Asunto(s)
Lesiones Encefálicas/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Hemiplejía/diagnóstico por imagen , Adolescente , Factores de Edad , Lesiones Encefálicas/complicaciones , Lesiones Encefálicas/fisiopatología , Corteza Cerebral/fisiopatología , Niño , Femenino , Hemiplejía/etiología , Hemiplejía/fisiopatología , Humanos , Imagen por Resonancia Magnética/tendencias , Masculino , Tamaño de los Órganos/fisiologíaRESUMEN
BACKGROUND: Periventricular white matter (WM) hyperechoic flares that do not evolve into cystic lesion(s) are frequently encountered on cranial ultrasonography (CUS) of preterm infants. Subjective interpretation of its presence, however, is challenging and its association with maturation and neurodevelopment remains undefined. OBJECTIVES: To determine the relationship between quantitative WM echogenicity and postnatal and postmenstrual ages and the relationship between quantitative WM echogenicity and neuromotor development at term equivalent. METHODS: We measured the mean pixel brightness intensity at the frontoparietal and parieto-occipital WM, choroid plexus and calvarium bone on sequential neonatal CUS scans of preterm infants born at <34â weeks gestation. The relative echogenicity (RE) was derived by dividing the mean WM echogenicity to that of the choroid plexus (RE(CP)) or bone (RE(BN)). The Lacey Assessment of the Preterm Infant was administered before discharge. RESULTS: 58 preterm infants (the mean gestational age 30.6±2.3â weeks and the mean birth weight 1211.9±224.7â g) were included. The RE(CP) of the frontoparietal WM decreased significantly with advancing postnatal and postmenstrual ages (r=-0.4, p<0.0001). The RE(BN) values of the frontoparietal and parieto-occipital WM during intermediate and late predischarge CUS studies, respectively, were significantly associated with neuromotor status at term (p<0.05). The RE(CP) and RE(BN) measured during the first week of life were not associated with neuromotor status at term. CONCLUSIONS: Quantitative measurements of the periventricular WM echogenicity are feasible in neonatal CUSs of premature infants and may reflect microstructural developmental changes. An optimal echogenicity quantification technique and its correlation with long-term outcome remain to be determined.