Two-year follow-up study of white matter structures in 2-3 years old children with autism spectrum disorder

Abstract

Objective To explore the developmental characteristics of white matter volume in autism spectrum disorder (ASD) children longitudinal. Methods From May 2011 to September 2014, 37 ASD children (ASD group) and 27 developmental delays (DD) children (control group) were treated at the Child Mental Health Research Center, Nanjing Brian Hospital Affiliated of Nanjing Medical University, and the children whose age, gender and developmental quotient matched with the ASD children were scanned by structure magnetic resonance imaging (sMRI) at the age of 2-3 years old and 4-5 years old respectively.Region of interest(ROI) technology was adopted to investigate the change of the cerebrum white and the sub-lobes structure white matter volume with time.Then the correlation between clinical symptoms and brain white matter volume changes was analyzed. Results Among the 2-3 years old, compared with the control group, the white matter volume of the total brain[(383 521.84±6 427.57) mm3vs. (364 014.06±6 856.97) mm3], the left cerebral hemisphere [(191 609.35±3 206.60) mm3vs. (181 695.89±3 389.54) mm3], temporal lobe [(41 860.49±816.38) mm3vs. (39 444.18±834.85) mm3] and the right temporal lobe [(21 312.79±414.07) mm3vs. (20 084.22±412.13) mm3] were significantly larger in the ASD group, and the differences were statistically significant (all P 0.05). Among the 4-5 years old, compared with the control group, the white matter volumes of the total brain[(417 651.42±6 443.86) mm3vs. (394 317.27±6 404.86) mm3], left cerebral hemisphere [(208 714.16±3 214.61) mm3vs. (197 192.82±3 262.02) mm3], right cerebral hemisphere [(208 937.26±3 242.09) mm3vs. (7 124.45±3 193.13) mm3], frontal lobe [(107 107.46±1 681.99) mm3vs. (100 326.19±1 883.24) mm3], left frontal lobe [(54 569.63±846.85) mm3vs. (51 177.25±979.09) mm3], right frontal lobe [(52 537.83±841.99) mm3vs. (49 148.94±928.31) mm3], temporal lobe [(45 189.75±833.29) mm3vs.(42 487.73±786.27) mm3], left temporal lobe [(22 204.21±411.77) mm3vs. (20 922.90±418.46) mm3], and right temporal lobe [(22 985.54±426.93) mm3vs. (21 564.83±378.78) mm3] were significantly larger in the ASD group, and the differences were statistically significant (all P 0.05). For longitudinal analysis, there was a significant difference in the white matter volume between the whole brain, left cerebral hemisphere, right cerebral hemisphere, frontal lobe, left frontal lobe, right frontal lobe, temporal lobe, left temporal lobe, right temporal lobe and the differences were statistically significant(F=5.521, 5.533, 5.459, 5.830, 5.800, 5.723, 4.857, 4.418, 5.159, all P<0.05). There was a positive correlation between the changes of the volume of whole brain, the white matter volume in the whole brain, bilateral cerebral hemisphere, frontal lobe, parietal lobe, right parietal lobe and Childhood Autism Rating Scale(r=0.367, 0.343, 0.321, 0.349, 0.296, 0.308, 0.351, all P<0.05). Conclusions Among the 2-3 years old, the white matter volume of the brain regions have been increased significantly in ASD.Among the 4-5 years old, the increase of the white matter volume of the brain regions implicated more widely which mainly concentrated in the frontal and temporal lobe in ASD.The severity of the clinical symptoms of ASD may be associated with the white matter volume of the total brain, bilateral cerebral hemisphere, frontal lobe, parietal lobe and right parietal lobe. Key words: Autism spectrum disorder; White matter; Volume; Magnetic resonance imaging; Longitudinal study