DTI Study Of White Matter In The Main Language-related Function Areas Of Children With Developmental Language Disorders

Objective:Diffusion tensor imaging(DTI)was used to investigate the changes in white matter fiber structure in the primary language-related functional areas of children with developmental language disorder(DLD).Materials and methods:The study enrolled 20 children(15 males and 5females)with developmental language disorder(DLD)between the ages of 2and 4,with an average age of 29.6 6.5 months,At the same time,20 healthy volunteers with age-and gender-matched were included as normal control(CP)group.The white matter bundles of interest(ROIs)in the major language-related functional areas(Broca area in the frontal lobe of the bilateral cerebral hemisphere,Wernicke area in the temporal lobe,and the bilateral arcuate bundles connecting Broca area and Wernicke area)were obtained by DTI,The DTI parameters of ROIs were measured,including anisotropic fraction(FA),average diffusivity(MD),axial diffusivity(AD)and vertical diffusivity(RD).The characteristics of the DTI parameter values are compared to their differences.At the same time,To evaluate the language development quotient(DQ)of DLD group by using Gesell Development Scale(GDS),and to explore the correlation between the average FA value of main ROIs and DQ of DLD group.Results:(1)The values of DTI parameters on the left and right sides of the CP group were compared.The values of FA in the left Broca area,Wernicke area and the upper and lower parts of the arcuate fiber bundle were higher than those on the right side,and the left side of the Wernicke area and the left upper arcuate fiber bundle.Above the right side,the difference was statistically significant,and there was no statistically significant difference in the remaining DTI parameter values.(2)The values of DTI in the left and right sides of the DLD group were compared.The FA value in the lower segment of the left arcuate fiber bundle was higher than that on the right side.The AD value in the left Broca area of the DLD group was higher than that on the right side,and the difference was statistically significant.There was no statistically significant difference in the DTI parameter values between the left and right sides.(3)Comparison of DTI parameter values between DLD group and CP group,Dro group double-sided Broca area,Wernicke area and double-sided arcuate fiber bundle upper FA value are lower CP)group,DLD group left Wernicke area,bilateral arcuate fiber bundle The upper and lower AD values were lower than the CP group,and the difference was statistically significant.The upper and lower RD values of the right arcuate fiber bundle in the DLD group were higher than those in the CP group,and the difference was statistically significant.There was no significant difference in the remainingparameters.(4)The mean FA value of the two-sided Broca and Wernicke was positively correlated with the language developmental quotient DQ.There was no significant linear relationship between the mean FA value of the upper and lower segments of the bilateral arcuate fiber bundles and the language developmental quotient.Conclusion:(1)We speculate that the white matter fiber bundles in the language-related functional areas of normal preschool children aged 2-4 years are in the dynamic development stage,but have partially formed the left hemisphere superiority.(2)Compared with the CP group,the FA value,AD value and RD value of the white matter fiber bundles in the main language-related functional areas of DLD children changed significantly,suggesting that there are different degrees of myelin dysplasia or damage in the white matter fiber bundle.(3)The bilateral FA value of Wronicke and Wernicke were positively correlated with the language developmental quotient DQ,and the mean FA value decreased with the decrease of language development quotient,suggesting the fiber bundle of Broca and Wernicke in children with developmental language disorder.It may be more susceptible to abnormal changes.