Brain Volumes in Autism and Developmental Delay - a MRI Study
Predescu, Elena, Sipos, Paul, Sipos, Roxana, Iftene, Felicia, Balázsi, Róbert, Journal of Evidence-Based Psychotherapies
The objective of this paper was to study brain volumes in children with autistic spectrum disorder (ASD) as compared to children with a developmental delay (DD). Fifteen children with autism and ten children with developmental delay, ages between 2 and 8 years old, were included in this MRI study. Total brain (TBV), grey matter (GM) and white matter (WM) volumes were measured using SPM5. Parents completed The Child Behaviour Checklist 1.5-5 (CBCL) for all the children included in the study. Our results do not indicate statistically significant differences between the two groups, but we observed a higher average of the measured brain volumes in the ASD group. A significant correlation was found between age and GM and WM volumes (for GM volumes Spearman's rho=.42, DF=23, p<.05 and for WM volumes Spearman's rho=.57, DF=23, p<.01). We performed a univariate descriptive statistic for CBCL subscale scores and a non-parametric correlation analysis between the three brain volumetric measures (TBV, WM and GM) and participants' scores on CBCL subscales. In both groups, correlations were found between the measured brain volumes and the scores of the CBCL Attention deficit/Hyperactivity Problems and Opposition Defiant Problems subscales. Unlike the correlations found in the ASD group, the DD group shows only positive correlations. This result suggests a possible moderator role of the disorder, in the relation between CBCL subscales and volumetric measures of the brain. Our data on the measured brain volumes of the two groups largely overlap those described in the literature. Structural measures interpreted in relation to standardized clinical scales can provide useful information for the field of pedopsychiatry.
Keywords: autism, developmental delay, MRI, brain volumes
The rapid development of the neurosciences field and the use of modern technologies have led to an explosion of information in terms of brain structure and function. Neuroimaging in child psychiatry has proven to be useful in understanding normal brain development process and changes that occur in different psychiatric disorders. Cerebral structural modifications correlated with functional ones are responsible for the development of clinical features and can offer the paraclinical support for diagnosis or treatment decisions. These modifications can be also predictors of illness progression in time.
Autism spectrum disorders (ASD) are characterized by atypical social interaction, verbal and nonverbal communication deficits, restricted areas of interest, stereotype behaviors. Autism is a heterogeneous syndrome with multiple etiologies and highly variable severity. Comorbidity with mental retardation is very frequent (in ~70% of the cases) and even when IQ is normal, cognitive profiles are difficult to specify? The prevalence of autism spectrum disorders (ASD) is considered to be approximately 4-10 per 1000 (Fombonne, 2003). Early diagnosis and better availability of specialized services can increase the number of reported cases.
Developmental Delays (DD) are a group of related disorders of early onset estimated to affect 5%-10% of children. Developmental Delay is present when functional aspects of a childfs development in one or more domains (gross/fine motor, speech/language, cognition, social/personal, and activities of daily living) are significantly delayed compared to the expected level for age (≥25% of the expected rate or a discrepancy of 1.5 to 2 standard deviations from the norm).
ASD and DD are significant pathologies in preschool children. They are important because they affect long-term functioning of the individual and involve huge costs for care and recovery. Both disorders are characterized by a particular developmental route that does not overlap with the path of normal development in relation to age. Differential diagnosis of preschool children with ASD or DD, with cognitive delay and emotional or behavioral symptoms, is extremely difficult, requiring a very careful clinical evaluation. …