Radiological evaluation of children with developmental delay using magnetic resonance imaging and proton MR spectroscopy

Background: Several factors like environmental, genetic, nutritional and chronic diseases affect the process as well as can have adverse effects on it in the form of delays in developmental milestones. The milestone delay can be evaluated using four domains of gross motor, fine motor, social and language skills. Developmental delay is defined as significant delay (more than two standard deviations below the mean) in one or more developmental domains. Global developmental delay is defined as significant delay in two or more developmental domains. Brain MRI is one of the major investigations of these patients. MRI is also used to examine the usual brain myelination patterns. Investigators have also used proton MR spectroscopy, an emerging MR imaging modality, in children to study neurodegenerative disorders, epilepsy, metabolic disorders, and pediatric neuropsychiatric disorders. Methods: This prospective observational study involved 100 children aged 6 months to 10 years with developmental delay, referred for brain MRI at a tertiary care center. MRI was performed on a 1.5-T system, and proton MRS was used to calculate N-acetyl aspartate (NAA), choline (Cho), and creatine (Cr) ratios in children with normal MRI findings. Children with progressive neurodevelopmental disorders, recognized syndromes, and CNS infections were excluded. Results: MRI findings were abnormal in 81% of the children, with neurovascular/traumatic lesions accounting for 59% and congenital/developmental anomalies for 15%. The most common findings involved white matter abnormalities (63%). MRS revealed abnormal neuro-metabolite ratios in 68% of children with normal MRI, indicating metabolic changes. Conclusions: MRI, combined with proton MRS, significantly improves diagnostic accuracy in children with developmental delay. While structural abnormalities were observed in 81% of children, MRS added value by detecting metabolic abnormalities in children with normal MRI findings.