Purpose

The role of sharps and spikes, interictal epileptiform discharges (IEDs), in guiding epilepsy surgery in children remains controversial, particularly with intracranial EEG (IEEG). While ictal recording is the mainstay of localizing epileptic networks for surgical resection, current practice dictates removing regions generating frequent IEDs if they are near the ictal onset zone. Indeed, past studies suggest an inconsistent relationship between IED and seizure onset location, though these studies were based upon relatively short EEG epochs.

Methods

We employ a previously validated, computerized spike detector, to measure and localize IED activity over prolonged, representative segments of IEEG recorded from 19 children with intractable, mostly extra temporal lobe epilepsy. Approximately 8 hours of IEEG, randomly selected thirty-minute segments of continuous interictal IEEG per patient were analyzed over all intracranial electrode contacts.

Results

When spike frequency was averaged over the 16-time segments, electrodes with the highest mean spike frequency were found to be within the seizure onset region in 11 of 19 patients. There was significant variability between individual 30-minute segments in these patients, indicating that large statistical samples of interictal activity were required for improved localization. Low voltage fast EEG at seizure onset was the only clinical factor predicting IED localization to the seizure onset region.

Conclusions

Our data suggest that automated IED detection over multiple representative samples of IEEG may be of utility in planning epilepsy surgery for children with intractable epilepsy. Further research is required to better determine which patients may benefit from this technique a priori.

Historically, adrenal cortico-tropic hormone (ACTH) was used as first line treatment for infantile spasms, however there has been increasing use of topiramate as initial therapy. Here we report a retrospective study of ACTH and topiramate as initial treatment of infantile spasms. The neurology patient database at the Children's Hospital of Philadelphia was searched using the ICD-9 code for infantile spasms, and 50 patients were randomly chosen for chart review. We identified thirty-one patients receiving either ACTH or topiramate monotherapy (ACTH, n = 12, topiramate n = 19) as a first line treatment for infantile spasms. Twenty-six patients were symptomatic and five cryptogenic. Six patients treated with ACTH had resolution of clinical spasms and hypsarrhithmia within a month, but three relapsed. Four of the nineteen patients treated with topiramate eventually, though over a period of 0,1,8 or 69 months, had resolution of spasms and hypsarrhythmia.