Deep brain stimulation of anterior thalamic nuclei for intractable epilepsy in Thailand: Case report

Neurostimulation can be an alternative treatment for medically intractable epilepsy, especially when the resective surgery could not be performed. The author reported a case of 19-year-old, right-handed male patient who had a history of intractable epilepsy for 11 years after post viral encephalitis associated with status epilepticus. Following the failure of antiepileptic medications and then resective surgery, anterior thalamic deep brain stimulation (DBS) was performed. Indirect targeting of anterior thalamic nuclei could not be used because of asymmetric brain shift from prior multilobar resections. Direct targeting of anterior thalamic nuclei from MRI T1 sequence, Short Tau Inversion Recovery (STIR) sequence combined neurophysiological mapping by microelectrode recording were used as a technique for implantation of DBS electrodes. The stimulation was turned on with 145 Hz, pulse width 90 microseconds, 5 volts with cycling mode 1 minute “on” and 5 minutes “0ff”. The antiepileptic medications continued the same as pre-operative state. Sixty percent seizure reduction was achieved in 24 months after surgery. There were no side effects of DBS during the follow-up period. Anterior thalamic DBS can be performed safely with satisfactory seizure outcomes. Direct targeting of anterior thalamic nuclei combination with microelectrode recording can be very helpful, especially when asymmetric basal ganglion structures were detected.