Deep brain stimulation of the anterior nucleus of the thalamus for drug-resistant epilepsy

Abstract

Despite the use of first-choice anti-epileptic drugs and satisfactory seizure outcome rates after resective epilepsy surgery, a considerable percentage of patients do not become seizure free. ANT-DBS may provide for an alternative treatment option in these patients. This literature review discusses the rationale, mechanism of action, clinical efficacy, safety, and tolerability of ANT-DBS in drug-resistant epilepsy patients. A review using systematic methods of the available literature was performed using relevant databases including Medline, Embase, and the Cochrane Library pertaining to the different aspects ANT-DBS. ANT-DBS for drug-resistant epilepsy is a safe, effective and well-tolerated therapy, where a special emphasis must be given to monitoring and neuropsychological assessment of both depression and memory function. Three patterns of seizure control by ANT-DBS are recognized, of which a delayed stimulation effect may account for an improved long-term response rate. ANT-DBS remotely modulates neuronal network excitability through overriding pathological electrical activity, decrease neuronal cell loss, through immune response inhibition or modulation of neuronal energy metabolism. ANT-DBS is an efficacious treatment modality, even when curative procedures or lesser invasive neuromodulative techniques failed. When compared to VNS, ANT-DBS shows slightly superior treatment response, which urges for direct comparative trials. Based on the available evidence ANT-DBS and VNS therapies are currently both superior compared to non-invasive neuromodulation techniques such as t-VNS and rTMS. Additional in-vivo research is necessary in order to gain more insight into the mechanism of action of ANT-DBS in localization-related epilepsy which will allow for treatment optimization. Randomized clinical studies in search of the optimal target in well-defined epilepsy patient populations, will ultimately allow for optimal patient stratification when applying DBS for drug-resistant patients with epilepsy.

Centromedian thalamic nucleus with or without anterior thalamic nucleus deep brain stimulation for epilepsy in children and adults: A retrospective case series

“…In our cohort, two out of three patients with focal epilepsy were responders (patients 10 and 11). Possibly, adding ANT stimulation may desynchronize cortical and thalamocortical activity and reduce seizure frequency from zones involving frontal and temporal structures connected to the Papez circuit [ 24 ]. Nonetheless, there is evidence from a retrospective cohort that CM stimulation alone can provide up to 68 % seizure reduction for patients with multifocal onset seizures [ 23 ].…”

Recommendations for the treatment of epilepsy in adult and pediatric patients in Belgium: 2020 update

“…It has been shown to reduce seizure frequency in adults and children, and has shown mild and mostly temporary stimulation-related side effects that are different from common side effects of AEDs [ 60 , 61 ]. DBS of the anterior nucleus of the thalamus (ANT-DBS) is an alternative neurostimulation modality that has shown long-term efficacy in drug-resistant patients [ 60 , 62 ]. ANT-DBS has been shown to be well tolerated; most complications are related to the implantation technique.…”

Recent antiepileptic and neuroprotective applications of brain cooling

“…One potential evidence based alternative to AEDs and surgical resection is neuromodulation by focal stimulation in the central nervous system, like the anterior thalamus deep brain stimulation [5] or stimulation of the vagus nerve on the neck [6]. The third option would be the application of focal brain cooling in cases of focal epilepsies where the epileptogenic zone is in an eloquent area.…”