Age of onset and outcome in 'acquired aphasia with convulsive disorder' (Landau-Kleffner syndrome).

The relationship between age at onset of language disorder and eventual outcome was examined in 45 cases of Landau-Kleffner syndrome reported in the literature, all of whom had been followed up to at least 12 years of age. A strong relationship was found, which is opposite to that for childhood aphasia after structural lesions of the left hemisphere; i.e. in Landau-Kleffner syndrome, the older the child at onset the better the prognosis for language.