Introduction Autism Spectrum Disorder (ASD): A neurodevelopmental disorder characterized by challenges in social communication and repetitive behaviors. Approximately 1 in 44 children are affected (CDC, 2023). Common delays include language, social skills, and cognition. Importance of MRI in ASD: MRI helps identify neuroanatomical differences in ASD, improving diagnostic accuracy and guiding clinical management. It is useful for distinguishing ASD from other conditions and identifying syndromic cases. Indications for MRI in ASD 1. Neurological Signs: Seizures, macrocephaly, motor delays. 2. Regression: Loss of language or social skills. 3. Atypical Physical Features: Congenital anomalies or dysmorphisms suggestive of syndromic ASD. 4. Diagnostic Uncertainty: Significant developmental delays with unclear diagnosis. Common MRI Findings in ASD 1. Macrocephaly and Brain Volume: Enlarged brain volume, especially in the frontal lobes during early childhood. (MR image of showing macrocephaly) Example: MRI shows increased brain volume. 2. Ventricular Enlargement: A most significant known linked finding was increased ventricular volume, which was notably higher in patients with ASDs, especially those with comorbidities. 3. Corpus Callosum and cerebellar Abnormalities: Thinning or absence of the corpus callosum, affecting brain hemisphere communication. Reduced cerebellar vermis size, may be linked to motor and cognitive issues. Example: MRI shows corpus callosum thinning. (MR image showing thin corpus callosum and another one with dysgenesis) 4. White Matter Connectivity: Altered white matter tracts, including reduced connectivity in the corpus callosum. Example: DTI shows disrupted white matter pathways. 5. Cortical Thickness and Gyrification: Abnormal cortical thickness and gyrification patterns. Example: MR image of Polymicrogyria in an autistic child. Impact on Clinical Management MRI helps differentiate ASD from other neurological conditions, informs prognosis, and guides early interventions. It also advances the understanding of ASD’s neurobiology for future treatments. Limitations: Many children with ASD have normal MRI findings, so imaging should complement clinical assessments for a comprehensive diagnosis. Conclusion MRI is critical for assessing developmental delays in ASD, particularly when neurological or syndromic features are present. Further research is needed to identify MRI biomarkers and neuroradiological features for ASD, enabling more targeted interventions. Read More
Meeting name: SPR 2025 Annual Meeting , 2025
Authors: Ibrahim Mohamed, Desilet-dobbs Debra
Keywords: Brain MRI, Corpus Callosum Morphology, Development