Abstracts

RATIONALE: To examine the clinical course and long-term management of patients after MST for Landau-Kleffner Syndrome.
METHODS: LKS, acquired epileptic aphasia, is a syndrome, which although rare, has profound effects on speech and behaviour. The epilepsy in the syndrome is neither prominent nor troublesome. Since first described in 1957 little effective treatment has been available. Morrell devised the surgical treatment of LKS, deducing correctly that LKS was a manifestation of secondary epileptogenesis and therefore would be amenable to this surgical procedure.
Between 1992 and 2002 10 patients were investigated and operated upon on the Denmark Hill site with a presumptive diagnosis of LKS. . All patients had severe speech disturbance, eight of the ten were mute or virtually so before surgery. Six patients had a severe behaviour disorder. All of the patients were investigated appropriately, within the limits of their behaviour disorder. These included MRI, speech and language assessment and neurophysiological tests of secondary epileptogenesis. All patients had carotid amytal tests and in two patients it was necessary to use intracranial electrodes. The last two patients operated had magnetic source imaging.
RESULTS: All of the patients underwent MST with electrocorticographic control. In 8 cases the operation was on the left side in two cases on the right side. There were no significant complications from the surgery except for a transient hemiparesis in the first patient that resolved within one week. In three patients there was evidence of relapse with deterioration or halting of speech reacquisition and the reappearance of ESES in the EEG. In one case this resolved spontaneously in the other two a further operation was required two years and one year after the first. In one patient, that was probably a wrong selection there was no improvement. All the other patients showed improvements in seizure control and behaviour. With a follow-up of 1 - 5 years in 9 patients, there was complete seizure freedom in two patients (Engel 1A) but significant improvement to Engel 3A or better in six of the remaining seven. In one case speech did not return, in the remaining seven patients for whom follow-up data is available, there was a significant and sustained improvement in speech as a result of the surgery.
CONCLUSIONS: In appropriately selected cases of Landau-Kleffner syndrome (acquired epileptic aphasia) multiple subpial transection will improve speech, behaviour and seizure control.