Electrical Brain Stimulation to Treat Drug Resistant Epilepsy in Children
The findings of a small study, led by researchers at King’s College London, suggest that electrical stimulation of the brain may be a safe and effective treatment for children with drug-resistant epilepsy, although further research is required. The work is published in the European Journal of Paediatric Neurology.
Limited information exists about the effects of brain stimulation in children and, according to the authors, “Given the significant long-term effects of chronic childhood epilepsy on educational attainment, employment, marital status, and psychological health into adulthood, this study may offer the potential to significantly improve the long-term quality of life of children with refractory [or drug-resistant] epilepsy.”
The study involved eight children with drug-resistant epilepsy who were already undergoing detailed investigation of their condition.Three of the children received deep brain stimulation (DBS) whilst the other five received a newer treatment called subacute cortical stimulation (SCS).
DBS is used to treat a number of neurological conditions and requires electrodes to be implanted within the brain. The device is then programmed to emit electrical pulses either continuously or at certain intervals. SCS is slightly less invasive and involves a relatively short period of stimulation (20-161 hours in this case) to the brain surface, following a 24 hour ‘baseline’ video EEG recording. SCS can be used both to treat epilepsy and to identify areas in which seizures originate. These regions can then be targeted either surgically or with continuous electrical stimulation.
The effectiveness of DBS in reducing seizures was assessed by comparing the frequency of the children’s seizures before treatment and after a 6-36 month follow-up period. SCS was evaluated by counting the number of seizures and interictal discharges (characteristic brain activity that occurs between epileptic seizures) before (baseline), during and after treatment.
Amongst the children who received DBS, two showed more than a 60% improvement in their seizure frequency and severity. One, in fact, had more than a 90% reduction in seizures, but the stimulation parameters had to be changed during follow-up. The third child did not show any improvement with DBS.
In the SCS group, four showed more than a 50% improvement in seizure frequency and a greater than 75% decrease in interictal (between seizure) activity. Two of these four in fact became seizure free (one after removal of their electrodes and the other after an area stimulated with SCS had been surgically removed). One child did not show any improvement with SCS.
Electrical stimulation was well-tolerated by the children, although one who received DBS experienced a worsening of seizures and another a worsening of behaviour.
These results suggest that electrical brain stimulation may be effective in children with drug-resistant epilepsy, although this was only a small study and larger ones are required. The authors emphasise that care should be taken to adapt brain stimulation to the developing brain of children, and highlight the need for further research to find the most suitable and least disruptive stimulation parameters.
An interview with one of the patients who underwent the procedure and is now seizure free was published in the Daily Express.
Note: The data from this study was analysed and published as part of an ERUK-funded project led by Dr Antonio Valentin, which focuses on SCS as a treatment for people with epilepsy. You can read more about the project here.
Authors: Dr Özge Özkaya and Delphine van der Pauw
Click here for more articles about other treatments for epilepsy.