Deep Brain Stimulation (Brain Pacemaker)

What is a deep brain stimulator?

Deep brain stimulation (DBS), also referred to as a brain pacemaker, is a neurosurgical procedure for treating various neurological disorders such as Parkinson’s disease, tremor, and depression. It involves implanting electrodes into certain brain regions and connecting them to an impulse generator that is implanted under the skin near the clavicle.

The brain is the central organ of our body, regulating various conscious and unconscious processes. It consists of trillions of nerve cells, called neurons. They are interconnected in a specific way so that they can coordinate complex functions. Neurons with similar or identical function are clustered together, allowing the distinction of different functional areas.

Neurological disorders can affect the neurons of the brain, ultimately impairing their function. Depending on the specific area, different functions may be affected. 

The principle of deep brain stimulation is based on implanting electrodes into specific brain areas and influencing the activity of the neurons through continuous high-frequency stimulation.

Brain pacemakers are primarily used for treating movement disorders or their symptoms. In addition, recent studies have shown promising results in the treatment of psychiatric disorders such as chronic depression or obsessive-compulsive disorder.

Over 80,000 patients have been treated with deep brain stimulation worldwide. It is particularly beneficial for patients with movement disorders to improve their quality of life.

What conditions can be treated using deep brain stimulation?

Deep brain stimulation is mainly used for treating Parkinson’s disease. However, it is also approved for other movement disorders such as Tourette syndrome, multiple sclerosis, dystonia, or essential tremor, that do not adequately respond to medications. It can also be a possible treatment option for epilepsy, after the origin of seizures has been determined.

It is assumed that DBS may also have positive effects on psychiatric disorders (e.g. depression and obsessive-compulsive disorder). However, its use remains largely experimental. It is also important to determine whether the depression or obsessive-compulsive disorder is a primary disorder or a secondary symptom of another underlying condition. 

This type of treatment is purely symptomatic. The above-mentioned conditions are not curable by DBS.

Requirements for a brain pacemaker

Before any intervention, the patient must be suitable for the treatment and fit enough for surgery. The patient’s general health status is assessed. Moreover, the diagnosis that requires DBS must be well established and confirmed. It is advisable to perform the assessment of the indication for DBS in a specialized center, where various neurological examinations take place.

This also includes psychological assessments, imaging studies of the brain, and in the case of Parkinson’s disease – an additional examination of symptoms, with and without medications. The motor symptoms may be recorded on video and used for comparison before and after surgery. Moreover, the use of scales for symptoms may be useful to document the severity of the condition.

Further examinations before surgery include speech therapy evaluation, neurosurgical assessment, and general assessment of surgical fitness. 

Procedure of deep brain stimulation

As for any other surgical procedure, patients must undergo a detailed preoperative consultation, regarding the risks and side effects, and have the opportunity to ask questions.

It is advisable to ask about the patient’s expectations regarding the surgery. This allows patients to get informed about which symptoms are likely to improve with DBS and which symptoms will remain unaffected. It allows the patients to better understand the capabilities of the said procedure.

Ideally, the procedure is performed under local anesthesia. This allows the patient to collaborate and inform the surgeon about any undesirable side effects such as numbness or speech difficulties during the surgery.

A precise visualization of the brain structures is essential to implant the electrodes accurately, ensuring precise stimulation. This process is known as electrophysiological mapping. It involves recording the electrical activity of neurons using microelectrodes, improving the accuracy of the final position of the electrodes.

For the procedure itself, a small burr hole is made into the skull for each electrode. A test stimulation is performed before the final implantation of electrodes. This is done to assess the effect on the symptoms and any possible side effects. 

The surgeon places the electrodes precisely into the target region of the brain under imaging guidance (CT and/or MRI). In most cases, the targeted regions include the basal ganglia, which play an important role in executing movements. The placement of the electrodes can take approximately four to eight hours.

Either immediately after surgery or after a short delay of a few days, a small device that delivers electrical impulses (hence why it’s referred to as the brain pacemaker) to the electrodes is implanted under the skin near the collarbone. This allows patients to adjust the electrical stimulation themselves.

What to consider after the surgery?

In general, patients should remain at the hospital for a few days after the surgery for observation. Once the patient’s general condition has stabilized, a decision is made on when the adjustment of the brain pacemaker will take place. This is typically between one to five weeks after surgery.

As the adjustment of the pacemaker requires the symptoms to be present, it may be useful to reduce or discontinue previously taken medications. The electrode contacts are then activated using different pulse widths and frequencies. Subsequently, the effects on symptoms as well as side effects are assessed. The optimal adjustment should be the most favorable ratio between therapeutic effect and side effects. This process can take some time and requires patience.

Once the optimal settings have been established, the patient gains control over the pacemaker. The patient can then independently adjust the settings, using a handheld device, within predefined limits set by the physician. Comprehensive instruction on the function and control of the device is crucial.

What side effects can occur after brain pacemaker implantation?

During surgery, complications such as bleeding or infection can occur in rare cases. However, the overall risk is very low. Side effects of the stimulation itself, if they occur, are mostly psychological and temporary. These may include symptoms of depression or euphoria. Such effects can be well controlled in most cases by adjusting the settings. 

What are the advantages and disadvantages of deep brain stimulation compared to other treatments?

In medicine, any therapy should provide the biggest possible benefit with the fewest side effects. This particularly applies to invasive procedures such as deep brain stimulation. Therefore, careful consideration of the advantages and disadvantages is required prior. 

The advantages of the DBS depend on the specific symptoms of the patient. For example, in Parkinson’s disease, the treatment is particularly effective for treating symptoms such as muscle restlessness or increased muscle tone. Posture, speech, and psychiatric and cognitive functions, do not respond to deep brain stimulation. Depending on which symptoms predominate, the procedure may be more appropriate in some cases and less appropriate in others.

An important advantage of deep brain stimulation is the reduction of previously required medication. This can reduce medication-induced side effects and interactions with other drugs.

Another advantage is that the patients can control the stimulation themselves. However, patients must have the cognitive capacity to do so. Independent control may not be feasible for elderly or severely ill patients. In such cases, device adjustments can be performed by a physician.

Disadvantages of deep brain stimulation are related to the above-mentioned side effects. Moreover, the benefits of the therapy cannot always be reliably predicted prior to surgery. It is therefore recommended to evaluate the advantages and disadvantages on an individual basis. The decision should be made jointly by the patient and physician – if appropriate, family members as well.

What physicians and clinics specialize in deep brain stimulation?

Although the methods and techniques in deep brain stimulation have been continuously evolving and improving, the procedure itself remains invasive in nature. Studies have shown that the success of the surgery depends heavily on the experience and expertise of the surgeon. Therefore, treatment should be carried out in a specialized center.

Comprehensive patient care is provided through interdisciplinary collaboration of specialist doctors in neurology, neurosurgery, and psychosomatics. Additionally, they collaborate closely with other healthcare professionals such as neuropsychologists and speech therapists.

We have made it our mission to connect patients with the most suitable physicians to ensure medical care at the highest possible level. All listed physicians and centers have been carefully reviewed and selected for their experience in the field of deep brain stimulation. They all have outstanding expertise and are awaiting your treatment request.