Vagus nerve stimulation: effectiveness and tolerability in 64 paediatric patients with refractory epilepsies.

AIM: We discuss the effectiveness, tolerability, and safety of vagus nerve stimulation (VNS) as adjunctive therapy in 64 paediatric patients with refractory epilepsies. MATERIALS AND METHODS: Sixty-four patients (34 male and 30 female) implanted with VNS for refractory epilepsy were analysed. Electroclinical features were compatible with Lennox-Gastaut syndrome in 46 patients, focal epilepsies in 10 patients, Dravet syndrome in three patients, epilepsy with myoclonic-astatic seizures in three patients, and West syndrome in two. The NeuroCybernetic Prosthesis (NCP) system (Cyberonics, Webster, TX, USA) was employed and the following stimulation parameters were used: output current of 1 to 2.5mA, signal frequency of 30Hz, signal pulse width of 500µs, and signal "on" and "off" times of 30  seconds and 5  minutes, respectively. RESULTS: Of 46 patients with LGS, 30 cases showed a significant improvement in seizure control, with a reduction in seizure frequency of at least 50%. Ten patients with focal epilepsy, three patients with myoclonic-astatic seizures, two patients with Dravet, and two patients with West showed a significant improvement in seizure control, with a reduction in seizure frequency of at least 50%. A good clinical response was evident early and efficacy progressively improved with the duration of treatment up to 36 months. In a significant number of patients, reduced seizure severity and shorter recovery time and hospital stay were also observed. VNS was well tolerated in all patients. CONCLUSION: VNS is an effective and well-tolerated treatment for paediatric patients with refractory epilepsies, improving quality of life and neuropsychological performance.

Hemispherectomy in pediatric patients with epilepsy: a study of 45 cases with special emphasis on epileptic syndromes.

OBJECTIVE: In this study we report the clinical outcomes of hemispherectomy for epilepsy in pediatric patients with special emphasis on the epileptic syndromes and their etiologies. MATERIAL AND METHODS: We retrospectively studied 45 patients with medically refractory epilepsy with hemispheric lesions who underwent hemispherectomy at the "Hospital de Pediatría Prof. Dr. Juan P. Garrahan", Buenos Aires, Argentina between February 1990 and February 2010. Patients had been assessed using a standard protocol involving clinical, neuroradiological, neurophysiological, and neuropsychological teams. RESULTS: Twenty-seven males and 18 females with a mean age of 8.5 years (range, 2 months to 18 years) who underwent epilepsy surgery for refractory epilepsy were assessed. The mean time of follow-up was 9.5 years (range, 1 to 16 years). The following epileptic syndromes were recognized: West syndrome in 15 patients (33.5%), Rasmussen syndrome in 13 (29%), focal symptomatic epilepsy in 8 (17.5%), startle epilepsy in 6 (13.5%), Lennox-Gastaut syndrome in 2 (5%), and continuous spikes and waves during slow sleep in 1 (2%). The surgical specimens revealed malformations of cortical development in 18 patients (40%), Rasmussen encephalitis in 13 (29%), porencephalic lesions in 10 (22%), gliosis in 2 (4.4%), tumor in 1 (2.2%), and Sturge-Weber syndrome in 1 (2.2%). CONCLUSION: The outcome of hemispherectomy in pediatric patients is good for those with refractory epilepsies, such as West syndrome, Lennox-Gastaut syndrome, epileptic encephalopathy with continuous spikes and waves during slow sleep, and startle epilepsy arising from a hemispheric lesion associated with hemiplegia.

Electroclinical overlap of two types of epileptic encephalopathy occurring in the same children in a certain age period?

In this study, we describe three patients who each had an electroclinical overlap of two different epileptic encephalopathies (EE), with onset in a certain age period. Patient 1 had electroclinical features compatible with continuous spikes and waves during slow sleep (CSWSS) syndrome that changed into Lennox-Gastaut syndrome (LGS) (symptomatic, cause porencephalic cyst) at the age of 8.5 years. Patient 2 had LGS which evolved into CSWSS at the age of 6 years (symptomatic, cause polymicrogyria). The third patient had cryptogenic CSWSS syndrome at age the age of 7 years which evolved into LGS at the age of 7.5 years. All three patients could be considered to have two EE: CSWSS syndrome and LGS or to have had overlapping features of these epileptic syndromes.

Long-term follow-up of the ketogenic diet for refractory epilepsy: multicenter Argentinean experience in 216 pediatric patients.

PURPOSE: In this Argentinean retrospective, collaborative, multicenter study, we examine the efficacy and tolerability of the ketogenic diet (KD) for different epilepsy syndromes. MATERIALS AND METHODS: we evaluated the clinical records of 216 patients started on the KD between March 1, 1990 and December 31, 2010. RESULTS: One hundred forty of the initial patients (65%) remained on the diet at the end of the study period. Twenty-nine patients (20.5%) became seizure free and 50 children (36%) had a 75-99% decrease in seizures. Thus, 56.5% of the patients had a seizure control of more than 75%. The best results were found in patients with epilepsy with myoclonic-astatic seizures, Lennox-Gastaut syndrome, and West syndrome. Good results were also found in patients with Dravet syndrome, in those with symptomatic focal epilepsy secondary to malformations of cortical development, and in patients with tuberous sclerosis. Seizures were significantly reduced in four patients with fever-induced refractory epileptic encephalopathy in school-age children and in two patients with epileptic encephalopathy with continuous spikes and waves during slow sleep. The median period of follow-up after discontinuation of the diet was 6 years. Twenty patients who had become seizure free discontinued the diet, but seizures recurred in five (25%). Of 40 patients with a seizure reduction of more than 50% who discontinued the diet, 10 presented with recurrent seizures. CONCLUSION: The ketogenic diet is a good option in the treatment of refractory epilepsy. After discontinuing the diet, seizures recurrence occurred in few patients.