Five right-handed children with Landau-Kleffner syndrome (LKS) were studied with EEG and single-photon emission computed tomography (SPECT) before and after 6 months of corticosteroid therapy at the Universities of Estadual de Campinas and Sao Paulo, Brasil. EEGs showed both focal and generalized spikes, and spike-wave bitemporal discharges. MRI was normal. Brain SPECT showed abnormal perfusion in the left temporal lobe. Steroids and AEDs had no significant beneficial effects on either aphasia or behavior. 
COMMENT. Landau-Kleffner syndrome is an acquired epileptic aphasia or verbal auditory agnosia affecting children between 2 and 5 years of age and characterized by profound language dysfunction, seizures, and/or a paroxysmal EEG abnormality, and associated with a generally poor prognosis. The EEG abnormality is frequently bilateral and localization of a focal temporal lesion is often difficult. Brain SPECT in the above study, and previously reported by Morrell et al, may show hypoperfusion of the left temporal cortex.
Subpial intracortical transection in LKS. Morrell and colleagues at Rush-Presbyterian-St Luke’s Medical Center and Epilepsy Center, Chicago, describe a methohexital suppression test which permits epileptiform potentials to stand out in an otherwise flat EEG. Using this technique to define a unilateral origin for the bilateral epileptiform discharge, 14 children with LKS were treated surgically by subpial intracortical transection. Eleven (79%) are now speaking, and 7 of these no longer require speech therapy. This method of treatment in selected cases appears superior to corticosteroids which have at best a temporary beneficial effect.