AbstractsMedical & Health Science

Neuroimaging assessment of Cortical Development and Corpus Callosum as predictive markers of neurodevelopmental outcome in small for gestational age fetuses

by Gabriela Egaña Ugrinovic




Institution: Universitat de Barcelona
Department:
Year: 2014
Keywords: Neurologia pediàtrica; Neurología pediátrica; Pediatric neurology; Escorça cerebral; Corteza cerebral; Cerebral cortex; Cos callós; Cuerpo calloso; Corpus callosum; Creixement fetal; Crecimiento fetal; Fetal growth; Ciències de la Salut
Record ID: 1125732
Full text PDF: http://hdl.handle.net/10803/259342


Abstract

1. INTRODUCTION Intrauterine growth restriction (IUGR) is diagnosed at the presence of an estimated fetal weight below the 10th centile and is a frequent condition in perinatal medicine, reaching a prevalence of 5-8% in live newborn babies being a major contributor of perinatal and long term morbidity, such as neurological deficits. We hypothesized that these neurological impairement are related to brain microstructural changes which might be characterized by fetal neuroimaging, either MRI or ultrasonography. Identifying fetuses at risk for abnormal neurodevelopment in fetal medicine lays the basis to perform specific strategies to potentially improve both pre and postnatal management, such as timely delivery, careful support for breastfeeding and a thoughtful use of this window of opportunity to improve their neurocognitive outcome through specific strategies. So the objective of this thesis was to identify brain imaging biomarkers that could predict an adverse neurological outcome in small for gestational age fetuses. 2. METHODS This is a prospective cohort study which included 2 study groups: AGA (adequeate for gestational age fetuses) with an estimated fetal weight >10th centile and, SGA (small for gestational age fetuses) with an estimated fetal weight <10th centile. A fetal ultrasound was performed to establish clinical group membership and Doppler evaluation. Then, either a MRI at 37 weeks was performed or a neurosonography during the 3rd trimester in order to assess cortical development, insular and corpus callosum morphometry. Once these babies were born, they underwent a neurobehavioral assessment during the neonatal period (NBAS) and a neurodevelopmental test at 2 years (Bayley-III). The analysis was focused on the evaluation of differences among study groups. As secondary analysis, linear regression was used to evaluate the relationship between brain development and postnatal neurological outcome adjusting by potentially confounders. Statistical anlyses were performed using the SPSS for Windows version 17.0 statistical software. 3. RESULTS The thesis led to five articles which are published in international journals. Maternal characteristics did not differ between the study groups. We found that late-onset IUGR fetuses showed a different pattern of brain development assessed by fetal MRI, expressed by deeper fissures, smaller brain volumes and a more pronounced right asymmetry. They also presented thinner cortex with lower fractional anisotropy values wich was significantly associated to worse NBAS test. Small fetuses presented smaller corpus callosum assessed by MRI and US, particularly in its posterior portion which was associated to worse neurobehavioral outcome. When we explored the correlation between brain structure and neurodevelopment at 2 years, we found that smaller measurements were associated to worse Bayley-III scores. 7. DISCUSSION Although previous studies have shown poorer neurodevelopmental outcome in term, none of them have provided information about their brain…