Repeated Oscillatory TMS Therapy of the Epileptogenic Cortical Area in Children With Focal CSWS

Continuous Spike and Wave during Sleep (CSWS) is a rare neurological disease with an incidence of 0.2 - 0.5% of childhood epilepsy. It is often accompanied by comprehensive damage to brain function and associated neurodevelopmental problems. It is an epileptic syndrome which seriously affects the cognitive function of children. While it can be treated with drugs, other modalities are being sought, especially, in cases that are resistant to standard treatment. One such approach that is being tested is repetitive magnetic stimulation (rTMS). Noninvasive magnet stimulation of the cerebral cortex is an important and useful technique in neuroscience research, as well as in diagnostic and therapeutic clinical investigations. Over the last three decades the magnetic stimulation procedure is being carried out using a device called transcranial magnetic stimulator (TMS), which uses a large hand-held electromagnetic coil passing high amplitude current to induce her rapid changing magnetic field at a single cortical site. TMS has found clinical application several neurological and psychiatric conditions such as stroke, major depression, migraine, movement disorders and Tourette syndrome. One limitation of conventional TMS, besides the bulkiness of the device and large amount of current involved, is that it allows stimulation at only one cortical site at a time.Dr. Santosh Helekar of Houston Methodist Research Institute (HMRI) and Dr. Henning Voss of Weill-Cornell Medical College (WCMC) have developed a compact portable and wearable multisite transcranial magnetic stimulation device called Transcranial Rotating Permanent Magnet Stimulator (TRPMS) that can deliver stimuli at multiple cortical sites simultaneously or sequentially. It uses rapidly rotating small high-strength permanent magnets to induce currents in the brain. As opposed to conventional TMS, the TRPMS device is also ideally suited to conduct double blinded placebo controlled studies because undetectable demagnetized magnets can be intermixed with actual magnet to allow rapid rotation of either type of magnets to be activated and one in the same device in a randomized protocol. Under a previously approved HMRI study protocol this new device has been shown to induce motor-evoked potentials (MEPs) in the thenar muscles by highly focused stimulation of the cortical representation in the precentral gyrus.

In the present study, the investigators would like to conduct a test to see the therapeutic effectiveness of focused TRPMS stimulation of the epileptogenic region found on scalp electroencephalogram (EEG) in patients with focal CSWS. The specific aim of the study are:

1. To look at the immediate benefit obtained by CSWS patients subjected to 10 minutes of one-time TRPMS-ECA (epileptogenic cortical area) stimulation; evaluated as a reduction in Spike-Wave Index (SWI) on EEG during sleep.

2. To look at duration of sustainability (hours) of change in SWI achieved post stimulation.

3. To look at the tolerability of patients in using TRPMS.