MRI of the brain in the evaluation of children with developmental delay.

Purpose. To analyze the diagnostic value of MRI in children with developmen tal delay. Materials and Methods. From 1991 to 1997, 224 examinations were performed. Retrospective analysis of clinical findings and diagnostic yield was carrie d out. Results. MRI was abnormal in 109 cases. It never resulted in any patient ca re modification, 55 malformations, 12 cases of cerebral atrophy, 7 cases of white matter disease and 2 patients with phakomatose were identified. Myel ination delay (26 cases), increased signal of posterior white matter on T2- weighted images (9 cases) or widened Virchow-Robin spaces (3 cases) were fr equently encountered, but it remained unclear whether they represented norm al variants or true abnormalities. Post ischemic lesions were identified in 10 cases. Frequency of abnormal studies was significantly lower in childre n with developmental delay and behavioral disorders than in patients with o ther clinical presentation. Conclusion. Diagnostic yield of cerebral MRI can justify its performance by comparison to other imaging modalities. It should be correlated with other investigations performed in a specialized unit. Its main interest is for c lassification and research. Risk of sedation or anesthesia should also be t aken in account. Risk can be lowered using adequately equipped MR units and organizing procedures in collaboration with anesthesiologists.