Neuroimaging in mental retardation

To determine the diagnostic yield of neuroimaging in a cohort of children with mental retardation of unknown origin.

Neuroimaging was performed in a total of 47 patients with developmental delay/mental retardation, where no etiologic diagnosis could be made following clinical examination and preliminary investigations.

Thirty (63.82%) children had abnormal neuroimaging findings of which 19 (42.42%) were specific abnormalities useful in arriving at etiological diagnosis. Positive outcome of neuroimaging increased with the severity of mental retardation and in presence of microcephaly and neurologic deficits other than mental retardation.

Neuroimaging should be the standard clinical practice for a child with global developmental delay where no cause is apparent after examination and relevant investigations.