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Vagus nerve stimulation (VNS) has emerged as a significant therapeutic intervention for individuals with drug-resistant epilepsy (DRE) throughout their lifespan. DRE is a debilitating condition characterized by recurrent seizures that do not respond to traditional antiepileptic drugs, imposing substantial physical, cognitive, and emotional burdens on patients. VNS involves the implantation of a device that delivers electrical impulses to the vagus nerve, a major nerve connecting the brain to various organs. The mechanism of action is complex and not yet fully understood, but VNS has been found to modulate abnormal electrical activity in the brain, reducing the frequency and severity of seizures. This non-pharmacological approach offers a valuable alternative for patients who have exhausted conventional treatment options, improves their quality of life, and provides hope for seizure control. Importantly, VNS has demonstrated efficacy across different age groups, from children to adults, making it suitable for lifelong management of DRE. Furthermore, long-term studies have shown sustained benefits and safety of VNS, with potential positive effects on cognitive function and mood regulation. As a result, VNS represents a promising adjunctive therapy that can significantly impact the lives of individuals with drug-resistant epilepsy, offering them renewed hope and the potential for a better future.
Paulo Niemeyer State Brain Institute, Rio de Janeiro, Brazil
*Address all correspondence to: sadandrea@yahoo.com.br
1. Introduction
Epilepsy is a neurological disorder characterized by a persistent tendency to generate epileptic seizures [1]. Epilepsy manifests with a variety of symptoms, ranging from temporary confusion and loss of awareness to convulsions and unconsciousness.
While most patients achieve seizure control with antiseizure medications (ASMs), approximately 30% of individuals experience drug-resistant epilepsy (DRE), defined as failure of adequate trials of two tolerated, appropriately chosen, and used ASMs schedules to achieve seizure freedom [2, 3, 4]. It significantly impacts patients’ daily lives, cognitive function, and psychosocial well-being. Managing DRE requires a multidisciplinary approach to address the diverse underlying etiologies and provide individualized treatment plans.
Surgical intervention has gained recognition as an effective alternative for individuals with pharmacoresistant epilepsy and is often considered when drug therapy fails to control seizures adequately. The goal is providing a chance for improved seizure control and enhanced quality of life [5, 6].
While surgical interventions have shown promising results, they may not be suitable for everyone. Non-surgical treatments offer alternatives for individuals who are not candidates for surgery or prefer less invasive approaches. One such non-surgical option is vagus nerve stimulation (VNS), which involves implanting a device that delivers electrical impulses to the vagus nerve, a major nerve in the neck. VNS can help reduce seizure frequency and intensity, although it may not eliminate seizures entirely [7].
Vagus nerve stimulation (VNS) is a non-pharmacological therapy that has been approved for the treatment of refractory epilepsy. The purpose of this chapter is to review the current literature on the use of VNS for the treatment of epilepsy and to discuss its mechanism of action, efficacy, and safety along lifespan.
VNS is a non-pharmacological treatment option, making it suitable for individuals who may not respond well to medications or are unable to tolerate their side effects. It can also be used in conjunction with medication, maximizing the chances of seizure control and improving overall outcomes for people with epilepsy.
In recent years, technological advancements have further improved the effectiveness and convenience of VNS therapy [8]. Newer devices offer increased customization and programming options, allowing healthcare providers to tailor treatment to each patient’s unique requirements [9]. Additionally, some VNS devices are equipped with responsive neurostimulation capabilities, meaning they can detect and respond to the early signs of seizures, potentially aborting them before they manifest [9].
2.1 The Vagus nerve
The vagus nerve is the longest cranial nerve, originating from the brainstem and extending down to the abdomen. It is composed of both motor and sensory fibers, which allow it to carry signals in two directions: from the brain to different organs (motor function) and from organs back to the brain (sensory function) [10].
The vagus nerve’s sensory fibers carry important information from the visceral organs back to the brain. These sensory signals help maintain homeostasis, allowing the brain to monitor and regulate various physiological processes.
In the vagus nerve, there are three main types of fibers: A fibers, B fibers, and C fibers. These fiber types differ in their diameter, conduction velocity, and the type of information they transmit. It’s important to note that while A fibers and B fibers are myelinated and transmit signals relatively quickly, it is in these fibers that the VNS acts preferentially. C fibers are unmyelinated and conduct signals more slowly.
2.2 VNS and epilepsy history
The use of electrical stimulation for therapeutic purposes dates back to the ancient Greeks, who used electrical eels to treat headache and gout. In the modern era, the first application of electrical stimulation for therapeutic purposes was in the 18th century, when Benjamin Franklin used electricity to treat paralysis resulting from stroke [11].
The first documented attempt to use electrical stimulation for epilepsy was made in the late 19th century by English neurologist John Hughlings Jackson. He experimented with electrical stimulation of the vagus nerve to observe its impact on seizures [12]. It wasn’t until the late 20th century that VNS gained significant traction as a viable treatment option for epilepsy. In the 1980s, researchers started investigating the therapeutic potential of VNS in animal models, which showed promising results in reducing seizure activity [13, 14].
The use of VNS specifically for epilepsy was first reported in the 1980s when a team of researchers at the University of Alabama in Birmingham implanted a VNS device in a patient with refractory epilepsy [15]. The patient experienced a significant reduction in the frequency and severity of seizures, and subsequent studies confirmed the device’s efficacy in reducing seizure frequency in patients with refractory epilepsy [16].
Thereafter, prospective randomized clinical trials were carried out, and approval for use in patients with refractory epilepsy occurred in 1994 and 1997 in Europe and the United States, respectively [17]. Approval by ANVISA (National Health Surveillance Agency) for use in Brazil occurred in 2000. Recently, the neuromodulation committee of the Brazilian League of Epilepsy published recommendations for the use of the vagus nerve stimulator and stimulation deep brain [18].
The development of VNS devices has undergone significant improvements since the first clinical trials in the 1980s. The first-generation VNS device, developed by Cyberonics Inc., was implanted in the chest and connected to the vagus nerve via a lead wire. This device delivered fixed-frequency stimulation and required frequent adjustments to optimize therapeutic effects. Over the years, advancements in technology have led to the development of more advanced VNS devices. These newer devices allow for better customization of stimulation parameters and offer improved patient comfort and convenience.
Since then, VNS has been increasingly used as an adjunctive treatment for individuals with epilepsy, particularly those who do not respond well to medication. The therapy has demonstrated efficacy in reducing seizure frequency, improving quality of life, and providing an alternative option for patients who may not be suitable candidates for other forms of epilepsy surgery [7, 19].
In recent years, VNS has also shown potential for the treatment of other neurological and psychiatric conditions, such as depression and anxiety disorders. Ongoing research continues to explore the full range of therapeutic applications and optimize the effectiveness of VNS as a treatment option.
2.3 VNS mechanism of action
The mechanism of action of VNS is complex and not fully understood, but it is thought to involve a combination of effects on the central nervous system (CNS), autonomic nervous system (ANS), and immune system.
The afferent fibers of the vagus nerve transmit signals from the body to the CNS, providing sensory information about various physiological processes. The efferent fibers of the vagus nerve, on the other hand, transmit signals from the CNS to various organs and tissues in the body, regulating their function. The vagus nerve plays an important role in regulating many physiological processes, including heart rate, blood pressure, respiration, digestion, and immune function.
The mechanism of action of VNS involves various pathways, including the locus ceruleus, solitary tract, raphe nuclei, and cortical areas. The vagus nerve projects to various regions of the cerebral cortex, including the prefrontal cortex. Activation of the vagus nerve through VNS can lead to increased cortical excitability and the modulation of neural networks involved in cognition and emotional processing.
The locus ceruleus receives direct projections from the vagus nerve and is densely innervated by its fibers. This suggests that the locus ceruleus is a key player in mediating the effects of VNS on epilepsy [20]. The activation of the vagus nerve during VNS leads to the stimulation of the locus ceruleus, triggering a cascade of events that may contribute to its therapeutic effects [20, 21]. One of the major neurotransmitters released by the locus ceruleus is norepinephrine [22]. Norepinephrine has been shown to have both antiepileptic and proconvulsant properties, depending on the specific brain region and receptor subtype involved.
Furthermore, the locus ceruleus is interconnected with other brain regions implicated in epilepsy, such as the hippocampus and the cortex [23]. These connections allow for the integration of signals from the locus ceruleus with the broader epileptic network. Through its projections, the locus ceruleus can influence the excitability of these regions, potentially dampening epileptic activity. So, it contributes to the overall modulation of neuronal excitability and seizure activity by modulating the activity of inhibitory and excitatory neurotransmitters, as well as interacting with key brain regions involved in epilepsy.
Regarding neurotransmitters, studies have shown that VNS can modulate the release of neurotransmitters such as gamma-aminobutyric acid (GABA) and glutamate, which play critical roles in regulating neuronal excitability and seizure activity [24]. By increasing GABAergic inhibition and decreasing glutamatergic excitability, VNS helps to restore the balance of neurotransmission, thereby reducing the likelihood of seizures.
VNS has been found to influence EEG synchrony in individuals with epilepsy. Abnormal EEG synchrony, characterized by excessive synchronization or desynchronization, is often observed in epilepsy. VNS has been reported to modulate this abnormal synchrony and promote more balanced and coordinated neural activity. The exact mechanisms through which VNS achieves this effect are not yet fully understood, but it is thought to involve the modulation of neurotransmitters and neural networks involved in seizure generation [25, 26].
VNS has been shown to have modulatory effects on brain metabolism, particularly in regions associated with mood regulation, cognition, and seizure control. It is believed that VNS influences brain metabolism through its impact on neurotransmitter systems, neuroplasticity, and the autonomic nervous system. VNS has been shown to affect brain metabolism through its impact on cerebral blood flow and glucose utilization [27, 28, 29]. Research studies using neuroimaging techniques have demonstrated that VNS can increase regional cerebral blood flow and enhance glucose uptake in certain brain regions involved in seizure generation and propagation. This increased metabolic activity in these regions may promote the normalization of neuronal function and decrease seizure activity.
Finally, VNS is thought to modulate the immune system, which plays an important role in many physiological processes, including inflammation, wound healing, and tissue repair. VNS has been shown to reduce inflammation in animal models of arthritis and other inflammatory conditions, suggesting that it may have therapeutic potential for these conditions [30, 31].
Neuroplasticity is also important in seizure control. The proteome of postsynaptic density (PSD) is a protein complex located in the postsynaptic membrane, responsible for the structure, function, and plasticity of excitatory synapses in the central nervous system. It also known that neuronal activity regulates the protein composition of PSD. Researchers identified increased these protein content due to VNS showing the contribution to the plasticity of excitatory synapses [32].
The mechanism of action of VNS is intricate and not yet comprehensively understood. However, it is believed to involve a combination of influences on the central nervous system (CNS), autonomic nervous system (ANS), and immune system. To completely understand the mechanisms underlying the therapeutic effects of VNS, further research is required.
2.4 VNS surgical technique
I will describe a general overview of the surgical technique; please note that specific details and variations may exist depending on the patient, surgeon, and the device being used.
Here is a general description of the surgical technique for implanting a vagus nerve stimulation device:
2.4.1 Preoperative preparation
Before the surgery, the patient is typically evaluated and prepared for the procedure. This may involve conducting preoperative tests, reviewing the patient’s medical history, and discussing any potential risks or complications.
2.4.2 Anesthesia
The surgery is usually performed under general anesthesia, ensuring that the patient is unconscious and does not feel any pain during the procedure.
2.4.3 Incision
The surgeon makes a small incision, typically on the left side of the chest, just below the collarbone. The exact location of the incision may vary based on the surgeon’s preference and the patient’s anatomy (Figure 1).
Figure 1.
Description of the cervical and thoracic incision.
2.4.4 Pocket creation
A small pocket is created under the skin to hold the VNS device. This pocket is usually made in the upper chest area, but it can also be placed in the abdomen if necessary.
2.4.5 Lead placement
The surgeon carefully dissects down to the vagus nerve, usually located in the neck area. Two small electrodes, or leads, are wrapped around the vagus nerve. One lead is placed closer to the brainstem, while the other is positioned closer to the chest (Figures 2 and 3).
Figure 2.
Vagus nerve exposure.
Figure 3.
Lead placement.
2.4.6 Tunneling
The leads are then tunneled beneath the skin from the neck area to the pocket created in the chest. The surgeon uses specialized instruments to carefully guide the leads to the desired location.
2.4.7 Connection
The leads are connected to the VNS device, which is placed in the pocket. The device is usually about the size of a silver dollar and contains a battery, electronics, and programming capabilities.
2.4.8 Closure
The incision is closed using sutures or surgical staples, and a sterile dressing is applied to the wound site.
2.4.9 Programming
After the surgery, the VNS device needs to be programmed to deliver the appropriate electrical impulses. This is typically done during a follow-up visit, using a handheld programming device that communicates with the implanted device.
It’s important to note that VNS surgery carries certain risks and potential complications, including infection, bleeding, vocal cord dysfunction, device malfunction, and side effects related to nerve stimulation. The patient will be closely monitored after the procedure, and postoperative care instructions will be provided to aid in the healing process.
The specific details of the surgical technique may vary based on the patient’s individual circumstances, the surgeon’s expertise, and the specific VNS device being used.
Epilepsy affects people of all ages, including children. Despite pharmacological treatment, a significant proportion of pediatric patients continue to experience seizures and suffer from the adverse effects of medication. In such cases, alternative treatment options like vagus nerve stimulation (VNS) have emerged as a viable option.
3.1.1 Seizure reduction
VNS has demonstrated efficacy in reducing seizure frequency and intensity in children with epilepsy. Several clinical trials and observational studies have reported a significant reduction in seizure frequency by approximately 50% or more in a substantial proportion of pediatric patients [33, 34, 35].
Epilepsy has a complex etiology, and while it can be caused by a variety of factors, including brain injury, infections, or tumors, genetics play a significant role in the development of certain types of epilepsy. Advances in genetic research have led to the identification of numerous genes associated with various epilepsy syndromes. Research on the efficacy of VNS in genetic etiologies is still relatively limited, but several studies have explored its potential benefits in specific conditions.
Vagus nerve stimulation (VNS) has been the subject of investigation for several monogenic disorders, including Rett syndrome, Angelman syndrome, and Dravet syndrome. Initial research indicates that VNS could potentially improve respiratory function, heart rate variability, and overall behavioral functioning in individuals with these disorders [36, 37]. In the case of Angelman syndrome, researchers have reported improvements in communication skills, behavior [38].
Regarding Dravet syndrome, VNS has been investigated as an adjunctive treatment option, and studies have reported a reduction in seizure frequency and severity, as well as improvements in overall quality of life and cognitive function [39, 40]. In tuberous sclerosis, VNS is one of the therapeutic options that has shown promising efficacy in the management of seizures associated with tuberous sclerosis [41, 42].
VNS has been shown to provide sustained seizure reduction over an extended period. Studies have reported a decrease in seizure frequency even after several years of VNS therapy, with some patients experiencing complete seizure control [43, 44, 45].
In conclusion, VNS has demonstrated efficacy in reducing seizures and improving quality of life among children. It provides an additional treatment option for those who have refractory epilepsy and may not respond to traditional antiseizure medications. However, the response to VNS therapy can vary, and careful evaluation and consideration of individual cases are necessary. A collaborative approach involving medical professionals experienced in DRE is crucial in determining the most appropriate treatment plan for each patient.
3.1.2 Safety
When it comes to the safety of VNS in children, it’s important to note that research and clinical experience in this area are more limited compared to adults. Nevertheless, several studies and clinical trials have been conducted to evaluate the safety and effectiveness of VNS in pediatric patients.
Overall, the available evidence suggests that VNS is generally safe for use in children. The most common side effects reported include hoarseness of voice, cough, throat pain, and difficulty swallowing, which are usually mild and transient. These side effects are believed to be related to the stimulation of the vagus nerve and the muscles of the larynx [44, 46, 47, 48].
Ongoing monitoring and follow-up care are essential to ensure the safety and effectiveness of VNS in children. Regular visits to the healthcare provider will allow for the assessment of any potential side effects or complications and adjustments to the stimulation parameters if needed.
3.2 VNs and adults
3.2.1 Seizure reduction
The use of VNS in adults has been used for decades since the first clinical trials. VNS therapy has shown effectiveness in reducing the frequency, severity, and duration of seizures. Research and clinical studies have provided evidence of seizure reduction in adults undergoing VNS therapy [49, 50]. The reduction in seizure frequency varies from person to person, and some individuals experience significant seizure reduction, while others may experience more modest improvements. It is important to note that VNS therapy does not guarantee complete seizure freedom but aims to decrease seizure frequency and improve quality of life.
In most published studies, the response rates for implantable VNS vary between 45% and 65% [51, 52]. Kawai et al. observed a median reduction in seizures of 25.0%, 40.9%, 53.3%, 60.0%, and 66.2% at 3, 6, 12, 24, and 36 months, respectively [52].
Over time, the benefits of VNS therapy may become more pronounced. Initially, the stimulation parameters may be adjusted to find the optimal settings for each individual, and it can take several months or longer to observe the full benefits of treatment. The response rate tends to improve over time significantly between the second and fifth year [53]. These observations could be related to neuroplasticity with neosynaptogenesis, as shown by Cramer et al. [54].
Overall, VNS therapy has demonstrated its potential to reduce seizure frequency and improve the quality of life for adults with epilepsy. However, it is important to consider the eligibility, discuss potential risks and benefits, and determine if it is an appropriate treatment option for their specific condition.
3.2.2 Safety
The implantation procedure carries some inherent risks, including infection, bleeding, and potential damage to surrounding structures. However, these risks are relatively low and can be minimized through proper surgical techniques and postoperative care [51].
The VNS device itself may cause some side effects or complications. These can include hoarseness or voice changes, coughing, shortness of breath, tingling or prickling in the skin, neck pain, and headache. However, many of these side effects are temporary and tend to diminish over time [49].
Regarding sleep disorders, VNS has the potential to alter breathing patterns and potentially lead to more episodes of apnea or hypopnea [55]. This effect appears to be more pronounced during periods when the VNS device is active; however, it can occur during OFF periods [56].
3.3 VNS and elderly
While the use of VNS in the elderly population is generally considered safe, there is limited research specifically focused on its efficacy in this age group.
3.3.1 Seizure reduction
The evidence for VNS efficacy in elderly individuals is not as extensive. Studies have shown that VNS can lead to a reduction in seizure frequency in elderly patients with epilepsy [57]. While the specific seizure reduction rates may vary, research indicates that a significant proportion of elderly individuals experience a reduction in seizure frequency by at least 50% [57].
3.3.2 Tolerability and safety
VNS has generally been found to be well-tolerated and safe in the elderly population. Adverse effects are typically mild and transient, including hoarseness, coughing, and shortness of breath. Serious complications are rare but can occur, such as infection or stimulation-related adverse events [57].
3.3.3 Potential cognitive benefits
Some studies have suggested that VNS may have cognitive benefits for elderly patients with epilepsy, including improvements in memory and executive functions. However, further research is needed to establish a clearer understanding of the cognitive effects of VNS in this population [58, 59, 60].
Programming a VNS device involves setting parameters such as the stimulation strength, pulse width, frequency, and duty cycle to optimize seizure control. Here’s a description of how to program VNS for epilepsy, including setting the duty cycle:
4.1 Setting stimulation strength
This initial programming session typically takes place a few weeks after the VNS device implantation surgery, allowing for recovery and healing.
Stimulation strength refers to the intensity of the electrical pulses delivered to the vagus nerve. It is usually measured in milliamperes (mA). Typically, we should start with a conservative stimulation strength and gradually increase it over time to achieve optimal seizure control while minimizing side effects.
According to clinical studies, the initial current should start with 0.25 and gradually increase by 0.25 at each visit until reaching the response dose. A computational study showed that a current of 1.75 to 2.0 should be enough to activate all vagus nerve fibers [61]. Specifically, the population-level target output current for VNS therapy is recommended to be set at 1.625 mA [62]. Patients who are gradually adjusted to output currents close to the desired level of 1.61 mA tend to experience fewer adverse events related to stimulation compared to those who are adjusted to higher or lower levels. Therefore, when determining the ideal dosage for individual patients, the primary factor to consider should be the output current. However, it’s crucial to acknowledge that certain patients may require VNS output currents that deviate from the target level established for the general population, based on their specific circumstances.
4.2 Adjusting pulse width and frequency
Pulse width refers to the duration of each electrical pulse delivered by the VNS device, usually measured in microseconds (μs). A typical range for pulse width is 130–500 μs. However, biophysical data and modeling further support the use of pulse widths at or below 250 milliseconds, with lower pulse widths requiring an increase in the selected output current [62].
Frequency refers to the number of pulses delivered per second, measured in Hertz (Hz). Common frequencies range from 20 Hz to 30 Hz. Regarding the frequency of VNS therapy, there is currently insufficient robust data to advocate for the use of frequencies other than 20, 25, or 30 Hz in epilepsy to maximize clinical response. Therefore, these frequencies should be considered as the primary options [62].
Generally, these parameters are more related to the management of adverse effects. However, they may also influence the effectiveness of seizure control.
4.3 Configuring duty cycle
Duty cycle refers to the proportion of time the VNS device is actively stimulating versus the total time. It is usually expressed as a percentage. The duty cycle can be adjusted to modify the amount of stimulation delivered by the device.
A higher duty cycle means the device is actively stimulating for a larger proportion of time, which may provide increased seizure control but may also increase side effects. Conversely, a lower duty cycle means the device is stimulating for a smaller proportion of time, potentially reducing side effects but potentially compromising seizure control.
The optimal duty cycle for everyone varies, and finding the right balance often requires iterative adjustments during follow-up appointments with the healthcare professional.
There is still no robust evidence relating working time to types of seizures or response to VNS, which should be individualized for each patient.
4.4 Magnet and autostim
The VNS magnet is a handheld device that enables patients to deliver additional electrical stimulation to the vagus nerve when needed. It consists of a small magnet that can be placed over the implanted VNS device, triggering an immediate and short-term increase in stimulation. The VNS magnet offers patients the ability to self-manage their symptoms and provides a sense of control over their treatment.
When the VNS magnet is placed over the implanted VNS device, it activates a magnet switch within the device, leading to an increase in electrical stimulation. This temporary augmentation of vagus nerve activity can help alleviate acute symptoms or enhance therapeutic effects. The magnet switch is designed to ensure patient safety by limiting the duration and intensity of the additional stimulation. So, VNS magnet can be used during seizure events to provide immediate supplementary stimulation, potentially aborting or reducing the intensity of seizures.
Autostimulation is a feature integrated into some VNS devices that enables automatic adjustment of stimulation parameters based on real-time monitoring of heart frequency. By continuously monitoring heart rate, the VNS device can autonomously modulate the stimulation parameters, optimizing therapy delivery without requiring direct patient intervention [63].
Lo et al. showed the added effectiveness of AutoStim in children undergoing VNS treatment. Seizure reduction showed a substantial improvement, increasing from 60 to 83% after replacing the battery with AutoStim. When categorizing the results using the McHugh classification, the percentage of children achieving class I and II outcomes (≥50% seizure reduction) rose from 70 to 90% [64].
The table below shows the suggested evolution of parameters according to visits (Table 1).
Parameters
Visit 1
Visit 2
Visit 3
Visit 4
Visit 5
Visit 6
Visit 7
Visit 8
Output (mA)
0.25
0.50
0.75
1.0
1.25
1.5
1.5
1.5
Frequency (Hz)
20/30
20/30
20/30
20/30
20/30
20/30
20/30
20/30
Pulse width (μs)
250/500
250/500
250/500
250/500
250/500
250/500
250/500
250/500
Time ON (s)
30
30
30
30
30
30
30
30
Time OFF (min)
5
5
5
5
5
5
3
1.8
Table 1.
A step-by-step guide to programming vagus nerve stimulation.
In summary, the available evidence supports the adoption of current manufacturer dosing recommendations for VNS therapy in epilepsy. Output current is a crucial consideration when determining the optimal dose for individual patients. Further research is needed to explore the relationship between time-to-dose and time-to-response, as well as the impact of dose adjustments in non-responsive and over-responsive patients. Careful consideration of both efficacy and side effects is necessary when determining the parameters for VNS therapy in clinical practice.
The use of VNS in the management of epilepsy throughout an individual’s lifespan offers significant benefits and has proven to be an effective treatment option. From early childhood to adulthood and into old age, VNS has shown promise in reducing seizure frequency and improving overall quality of life for individuals with epilepsy.
In children, VNS has been found to significantly decrease the number of seizures, allowing for better cognitive development and academic performance. It can also lead to a reduction in medication dosages and side effects, enhancing the child’s overall well-being.
During adolescence and adulthood, VNS continues to be a valuable adjunctive treatment for epilepsy. It can provide seizure control, reduce seizure intensity, and lessen the need for rescue medications. Moreover, VNS has shown potential in improving mood and reducing comorbidities such as depression and anxiety, which are often associated with epilepsy.
As individuals with epilepsy age, VNS remains a viable option for seizure management. It has demonstrated long-term efficacy and safety, helping to maintain seizure control and reduce the risk of injury that can arise from seizures. Additionally, VNS offers the advantage of being adjustable and adaptable to changing seizure patterns over time, allowing for personalized treatment.
In conclusion, VNS is a valuable treatment option for epilepsy across the lifespan. Its ability to provide long-term seizure control, reduce medication dosages and side effects, improve mood, and adapt to changing seizure patterns makes it a valuable adjunctive therapy. Further research and advancements in VNS technology will likely continue to enhance its effectiveness and expand its potential benefits for individuals living with epilepsy.
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Written By
Isabella D’Andrea-Meira
Submitted: 21 May 2023Reviewed: 24 May 2023Published: 23 June 2023
Open access peer-reviewed chapter
