Three types have been used in those who do not respond to medications: vagus nerve stimulation (VNS), anterior thalamic stimulation, and closed-loop responsive stimulation. Vagus nerve stimulation
Non-pharmacological modulation of neurotransmitters via high-level VNS (h-VNS) may reduce seizure frequency in children and adults who do not respond to medical and/or surgical therapy, when compared with low-level VNS (l-VNS). In a 2022 Cochrane review of 4 randomised controlled trials, with moderate certainty of evidence, people receiving h-VNS treatment were 73% more likely (13% more likely to 164% more likely) to experience a reduction in seizure frequency by at least 50% (the minimum threshold defined for individual clinical response). Potentially 249 (163 to 380) per 1000 people with drug-resistant epilepsy may achieve a 50% reduction in seizures following h-VNS, benefiting an additional 105 per 1000 people compared with l-VNS. This outcome was limited by the number of studies available, and the quality of one trial in particular, wherein 3 people received l-VNS in error. A sensitivity analysis suggested that the best case scenario was that the likelihood of clinical response to h-VNS may be 91% (27% to 189%) higher than those receiving l-VNS. In the worst-case scenario, the likelihood of clinical response to h-VNS was still 61% higher (7% higher to 143% higher) than l-VNS. Despite the potential benefit for h-VNS treatment, the Cochrane review also found that the risk of several adverse-effects was greater than those receiving l-VNS.
Chronic alcohol use increases the risk of epilepsy: those who drink six units of alcohol per day have a 2.5-fold increase in risk. Other risks include Alzheimers disease, multiple sclerosis, tuberous sclerosis, and autoimmune encephalitis. Getting vaccinated does not increase the risk of epilepsy. Malnutrition is a risk factor seen mostly in the developing world, although it is unclear however if it is a direct cause or an association. People with cerebral palsy have an increased risk of epilepsy, with half of people with spastic quadriplegia and spastic hemiplegia having the disease. Mechanism
Normally brain electrical activity is non-synchronous, as large numbers of neurons do not normally fire at the same time, but rather fire in order as signals travel throughout the brain. Neuron activity is regulated by various factors both within the cell and the cellular environment. Factors within the neuron include the type, number and distribution of ion channels, changes to receptors and changes of gene expression. Factors around the neuron include ion concentrations, synaptic plasticity and regulation of transmitter breakdown by glial cells. Epilepsy
The exact mechanism for epilepsy is unknown, but a little is known about its cellular and network mechanisms. However, it is unknown under which circumstances the brain shifts into the activity of a seizure with its excessive synchronization. Changes in MicroRNAs (miRNAs) levels seems to play a leading role.