Tiny Corpus Callosum In The Newborns With Meconium-stained Amniotic Fluid May Result In Delayed Development:A Retrospective Study

BackgroundWhen the fetal was in hypoxia in-utero,the meconium would be leaked into the amniotic fluid,inducing meconium-stained amniotic fluid(MSAF),which is regarded as a good index of fetal distress.In addition,if this condition persisted,the fetal or the newborn would suffer irreversible ischemic brain injury.What's more,he could sustain delayed development,such as cerebral paralysis(CP).As corpus callosum is the largest white matter fiber tracts in human beings,connecting both sides of hemisphere,transmitting the information of motion,sense and cognition,it is a remarkable and sensitive sign of the development and maturity of the cerebrum.While the newborn is at risk of hypoxia,the white matter will result in myelination disorder,leading to tiny corpus callosum.ObjectiveIn order to understand the relationship between tiny corpus callosum with meconium-stained amniotic fluid and delayed development,a retrospective study was raised in the term infants with meconium-stained amniotic fluid to explore their corpus callosum.Materials and methods1.PatientAs a retrospective study,the term infants born from Jan 1,2012 to Dec 31,2015 and delivered into the neonatal intensive care unit(NICU)were analyzed.They were primarily divided into two groups,the thick-meconium-stained amniotic fluid as the experimental group and the amniotic fluid clear as the control group.Exclusion:(1)the mother had infection,gestational diabetes mellitus and other disorders during pregnancy;(2)the newborn is diagnose of chromosome abnormality,inherited metabolic diseases,fatal structural abnormality(such as severe congenital heart disease),anencephaly,hypoxic-ischemic encephalopathy(HIE),central nervous system infection(such as meningitis),intracranial hemorrhage,bilirubin encephalopathy,shock,small for gestational age(SGA),neonatal hypoglycemia;(3)the newborn has not got or need not cerebral MRI in hospital.2.Clinical dataThe clinical data from the medical system was collected including the sex,the gestational age,the type of amniotic fluid,the birth weight,the score of NBNA(N eonatal Behavioral Neurological Assessment)and the score of CDCC(Children's Development Center of China)at one-year-old.3.MRI data3.1 The MRI data was classified into several parts,including the posterior limb of internal capsule(PLIC),thalamus,lentiform nucleus,head of caudate nucleus,paracentral cortex,cortico-spinal tract,brainstem,hippocampus,periventricular white matter,cerebellum,corpus callosum and the white matter in both hemispheres.3.2 Measurement of corpus callosumBefore the measurement of the corpus callosum,random numbers were given to each newborn for his image of MRI and all the information of the newborns respectively covered.The PACS(Picture Archiving and Communication system)was used as a semi-automated tool in our hospital,to draw lines of the corpus callosum on mid-sagittal MRI,and the length,the height,the thickness of the body,the genu and the splenium and the area of the corpus callosum were measured respectively.All the measurement was conducted by a radiologist two times and the average was taken.3.3 Statistical analysisThe data was analyzed by SPSS 19.0,?=0.05.3.3.1 Chi-square test was used to analyze the statistical significant difference between experimental group and control group on MRI data.3.3.2 The experimental group was divided into two groups,one as tiny corpus callosum(Group A)and one as normal corpus callosum(Group B).If there was statistical significance and homogeneity of variance between groups,ANOVA was used.3.3.3 Non-parametric test was used to assess the NBNA and CDCC between Group A,Group B and the control group.And Pearson correlation test was used between these items.Result1.The thick-meconium-stained amniotic fluid group and the clear amniotic fluid group had statistical significance in the area of corpus callosum and the white matter injury in the hemisphere.2.The newborns with thick-meconium-stained amniotic fluid and tiny corpus callosum had statistical significance in the length,the thickness of the body and the genu,and the area versus the ones with thick-meconium-stained amniotic fluid and normal corpus callosum,versus the ones with clear amniotic fluid.3.Three groups did not reach the statistical significance in NBNA,but in CDCC.In addition,the area of corpus callosum showed strong positive linear correlation with MDI.Conclusion1.Some of the newborns with thick-meconium-stained amniotic fluid will suffer tiny corpus callosum and the white matter injury in the hemisphere.2.When the newborns were born in thick-meconium-stained amniotic fluid,inaddition to tiny their corpus callosum,the abnormality will present in the length,the thickness of the body and the genu,and the area of the corpus callosum.3.The newborns born in thick-meconium-stained amniotic fluid with tiny corpus callosum had low MDI,and the MDI had strong positive linear correlation with the area of corpus callosum.