[Refractory partial epilepsy: morphological imaging in children]

The imaging approach to refractory partial epilepsy in children is essentially the same as the one used for any epilepsy at that age, except that surgery being generally proposed, it has to be oriented and complete. Yet there are differences. Sedation introduces a risk. The brain of the young child is still immature, and specially designed sequences are needed for proper imaging. Brain immaturity also modifies the usual image contrast and may conceal (or on the contrary enhance) an area of dysplasia. Repeating studies after a few months has to be considered. Obviously, the brain imaging study has to be closely oriented by the clinical and EEG findings and if necessary, by functional imaging data. The abnormalities are extremely diverse as compared to what is observed in an adult population. The brain may be "normal", or demonstrate only non-specific abnormalities. Among the specific lesions, scars are common, and above all, malformations, especially malformations of cortical development (even diffuse malformations are commonly expressed by partial seizures), including focal cortical dysplasias and their close relatives, dysplastic tumors. In children, the most common lesions in the temporal lobe are scars, tumors/dysplastic lesions and malformative lesions, while mesial sclerosis is significantly less common than in adults. In the event of a simple lesion, the decision for surgery on the basis of morphological data alone is more easily made in children than in adults.