Technology insight: neuroengineering and epilepsy-designing devices for seizure control

Abstract

Despite substantial innovations in antiepileptic drug therapy over the past 15 years, the proportion of patients with uncontrolled epilepsy has not changed, highlighting the need for new treatment strategies. New implantable antiepileptic devices, which are currently under development and in pivotal clinical trials, hold great promise for improving the quality of life of millions of people with epileptic seizures worldwide. A broad range of strategies to stop seizures is currently being investigated, with various modes of control and intervention. The success of novel antiepileptic devices rests upon collaboration between neuroengineers, physicians and industry to adapt new technologies for clinical use. The initial results with these technologies are exciting, but considerable development and controlled clinical trials will be required before these treatments earn a place in our standard of clinical care.

Figures

Figure 1

The Vagus Nerve Stimulator manufactured by Cyberonics, Inc. The implantable pulse generator is implanted under the left clavicle (A), and the stimulation lead is wrapped around the left vagus nerve in the neck (B). Image courtesy of Cyberonics, Inc., Houston, TX, USA.

Figure 2

The Medtronic Kinetra device. This device was used in the Stimulation of the Anterior Nucleus of the Thalamus in Epilepsy (SANTE) trial of open-loop brain stimulation for epilepsy. (A) A single device containing two pulse generators-one for each electrode-is implanted beneath the clavicle. (B) Intracranial electrodes are placed stereotaxically in the anterior thalamic nuclei bilaterally. Image courtesy of Medtronic. (C) Midsagittal and (D) transverse views demonstrating placement of stimulating electrodes in the thalamus.

Figure 3

The NeuroPace responsive neurostimulator. A schematic (A) and skull X-ray (B) of the NeuroPace responsive neurostimulator after implantation. The implantable device records, processes and transmits electroencephalographic signals, in addition to generating the electrical stimuli (C). The implantable depth (D) and strip (E) electrodes monitor brain signals and deliver electrical stimulation to stop seizures. Permission for panel A obtained from NeuroPace, Inc., Mountain View, CA, USA. Permission for panel B obtained from Nursing Spectrum Nurse Wire © 2004.