Diffusion Tensor Imaging Study Of White Matter Structure In Preschool Children With Autism

Objective:The core clinical symptoms of autism are social communication disorders and limited,stereotyped interests and behaviors.There have been reports in the literature that there are abnormalities in the white matter of adults and adolescents with autism.We proposed that "the structural integrity of white matter fibers in the brain of children with autism in preschool ASD children is reduced,and the topology of the white matter connection network in children with preschool autism(ASD)also altered.The hypothesis is that the abnormality of white matter structure in children with autism may be related to social communication disorders,with a view to discovering the difference in brain structure between preschool children with autism and normal developing children and the relationship between the white matter abnormability of preschool children and their clinical behavior.Methods:1.Using Diffusion Tensor Imaging(DTI)and using tract-Based Spatial Statistics to analysis differences in white matter fiber tracts across the brain between 50 cases of 2-6 years old children(male/Female ratio is 43/7,average age is 3.26±1.58 years)and 46 cases of age-and gender-matched normally developing children(TD)(male/female ratio is 38/8,average age is 3.47±1.65 years).2.Diffusion Tensor imaging fiber tract tracing(DTT)is used to extract the anisotropy scores(FA)of the corresponding white matter fiber tracts in the five-level model of social interaction to analyze preschool autistic patients Correlation between the integrity of white matter fiber bundles in the five-level model of social interaction in children and the scores of social interaction and communication on the ADI-R scale;3.Based on graph theory,50 cases of 2-6 years old children and 46 cases of age-and gender-matched normally developing children(TD)(male/female ratio of 38/8,average age of 3.47±1.65 years)brain structure network Perform analysis.Results:1.the study found that the scores of ABC,CARS and ADI-R in children with autism all met the diagnostic criteria for autism,the developmental quotient(DQ)scores was decreased in ASD groups.The superior left longitudinal tract(SLF),left corticospinal tract(CT),lower left longitudinal tract(ILF)and corpus callosum compression(sp1CC)of children with autism have significantly reduced FA values(FWE correction,p<0.05),and the CARS score is negatively correlated with the FA value of the corpus callosum;2.The upper left longitudinal tract Ⅲ(SLFⅢ,level 1),the left oblique frontal tract(FAT,level 2)and the lower left longitudinal fascia(ILF)in children with autism,Level 3)the FA value is reduced.In addition,the FA values of the upper longitudinal tract Ⅲ and the lower longitudinal tract are related to the ADI-R scale in autism;3.Children with preschool autism children show a reduction in the shortest path and an increase in global efficiency and cluster coefficients(p<0.05).The significant increase in node efficiency is mainly concentrated in the brain regions in para-limbic and limbic sysetem and the basal ganglia network.The brain area where the node efficiency is significantly reduced is located in the left supplementary motor area(p<0.05).Conclusion:the integrity of white matter fiber bundles in the left cerebral hemisphere of preschool children with autism have decreased.These abnormal white matter fiber bundles may be the basis of the daily abnormal behaviors in children with autism.The related reduction of white matter integrity in the five-level model of social communication is associated with social communication disorders in autism.The brain structure network topology of preschool children with autism has undergone major changes.The structural changes in the basal ganglia and the paralimbic-limbic system network and the left supplementary motor cortex may be potential imaging markers in preschool children with autism.