Radio-Frequency Electrostimulation in Treatment of Drug-Resistant Epilepsy

V.P. Bersnev, R.D. Kasumov, T.S. Stepanova, S.E. Karashurov, A. Darvish, S.V. Kravtsova, V.R. Kasumov

(Polenov Research Neurosurgical Institute, Saint Petersburg)

It is known, that 20-30% of patients with epilepsy are resistant to antiepileptic treatment. Drug-resistant epilepsy is one of the most complicated problems of epileptology (L.R. Zenkov et al., 2003). Search for new methods, which can be used in treatment of this large and grave contingent of patients, is grounded.

Employees of the Polenov Research Neurosurgical Institute have elaborated a new method, used for treatment of cases with drug-resistant epilepsy. It consists in chronic radio-frequency electrostimulation of nerves of a sinocarotid region with control of bioelectric parameters (its priority was confirmed on September 27, 2004 on the basis of claims for invention N 2004128670 and 2004128671). The main indications for using this method have been formulated. They are as follows:
1. A failure of former therapy with modern antiepileptic drugs.
2. Presence of marked side effects of antiepileptic drugs.
3. Patients with bitemporal (multi-focal) and primarily generalized epilepsy.
4. Inefficacy of adequate surgical methods, used in cases with locally conditioned forms of epilepsy.

Today we are carrying out study of 11 patients, aged 18-52. They have different forms of epilepsy with frequent uncontrollable seizures. The disease duration varies from 6 up to 40 years. The patients were examined on admission. It was done on the basis of a conventional preoperative diagnostic program for patients with epilepsy (ILAE, 1997), including a complex of clinical, electrophysiologic (EEG with mapping) and neurovisualizing (CT, MRI) examinations. All the cases had frequent polymorphic seizures with a progradient course of the disease in the anamnesis. They were represented by primarily generalized seizures with major tonoclonic fits, which were sometimes combined with epileptic absence (5), and partial (multi-focal) seizures with simple and complex fits of secondary generalization (6). EEG demonstrated focal (including bitemporal) and generalized paroxysmal activity with frequent bilateral spikes against a background of a disorganized rhythm; besides, there was a high convulsive activity of the brain. Electrostimulators were implanted into sinocarotid nerves of all cases under general anesthesia. Parameters and a mode of chronic stimulation were selected for each individual patient under EEG-monitoring. Efficacy of chronic radio-frequency electrostimulation was estimated during 18-22 months. There was positive clinical-electrophysiologic dynamics, watched in all the cases. Complete disappearance of seizures and more than 50% reduction of their rate were observed in 4 and 7 patients respectively. EEG examination was indicative of functional changes, manifesting themselves in decreased intensity of focal and generalized paroxysmal activity. There were no negative effects.

Thus, the proposed alternative method can be an important additional link in the system of complex surgical treatment of primary generalized and bitemporal (multi-focal) epilepsy, resistant to drug therapy.