How Is Deep Brain Stimulation Surgery Performed?
In brief: DBS surgery involves placing one or two thin electrodes into carefully selected brain targets and connecting them, through wires beneath the skin, to a programmable pulse generator usually implanted near the collarbone. The process includes detailed patient assessment, imaging-based planning, electrode placement, device implantation and postoperative programming.
Step 1: Confirming that DBS is appropriate
The process begins before the operating room. DBS is not selected solely because a person has Parkinson’s disease or because medication has been used for many years.
Assessment may include:
Confirmation of the Parkinson’s diagnosis
Review of motor fluctuations, tremor and dyskinesias
Examination during medication “off” and “on” states
Cognitive and psychological evaluation
Brain MRI
Review of general health and anaesthetic risk
Discussion of the patient’s individual goals
The team also determines which symptoms are likely—and unlikely—to improve.
Read Who Is a Suitable Candidate for DBS Surgery? for more information about patient selection.
Step 2: Selecting the brain target
The most frequently used targets for Parkinson’s disease are:
Subthalamic nucleus (STN)
Globus pallidus internus (GPi)
The ventral intermediate nucleus of the thalamus may be considered when tremor is the main treatment goal.
Target choice depends on the patient’s symptoms, medication response, dyskinesias, treatment goals and cognitive or psychiatric considerations. There is no single target that is automatically best for every patient.
Step 3: Planning the electrode trajectories
Detailed MRI—and in some centres CT imaging—is used to identify the target and plan a safe path through the brain.
The trajectory is designed to avoid:
Major blood vessels
The brain’s fluid spaces where possible
Functionally important structures
Unnecessary passage through cortical grooves
Stereotactic planning provides three-dimensional coordinates for accurate electrode placement. A frame-based or frameless guidance system may be used, depending on the centre and technique.
Step 4: Awake or asleep DBS surgery
DBS can be performed using an awake or asleep technique. Both approaches can be appropriate.
Awake DBS
The scalp is numbed and sedation is carefully managed. The patient may be asked to perform movement, speech or symptom tests while the surgical team assesses the effect of stimulation.
The brain itself does not contain pain receptors, although patients can feel pressure or discomfort from other parts of the procedure.
Asleep DBS
The electrode placement is performed under general anaesthesia using imaging and stereotactic guidance. Some centres also use microelectrode recording during asleep DBS.
The choice depends on the patient, target, equipment, surgical protocol and experience of the treating centre.
Step 5: Placing the DBS electrodes
One or two small openings are created in the skull. A thin electrode is guided along the planned trajectory into the selected deep brain target.
For bilateral symptoms, an electrode is commonly placed on each side of the brain. Symptoms on one side of the body are mainly controlled by stimulation on the opposite side of the brain.
Depending on the technique, the team may use:
Intraoperative imaging
Microelectrode recording
Test stimulation
Neurological examination
A combination of these methods
These steps help confirm electrode position and assess potential benefit or side effects.
Step 6: Confirming electrode position
After placement, imaging may be performed to confirm the location of the electrodes and check for complications.
The electrodes are secured at the skull. Their connector ends remain beneath the scalp, so no wires are visible externally after healing.
Step 7: Implanting the pulse generator
The electrodes are connected to extension wires that travel beneath the skin behind the ear and down the neck.
These wires connect to an implantable pulse generator, often called the battery or neurostimulator. It is usually positioned beneath the skin near the collarbone.
The pulse generator may be implanted during the same operation or in a separate procedure. This part is generally performed under general anaesthesia.
Rechargeable and non-rechargeable systems are available. Device selection should consider battery longevity, charging requirements, expected stimulation needs and patient preference.
Step 8: Healing before activation
DBS is not always activated immediately. The scalp and chest incisions are allowed to heal, and postoperative swelling is given time to settle.
Some patients temporarily notice symptom improvement before activation because of the effect of electrode placement. This is not the final programmed result and may fade during recovery.
Step 9: Activating and programming the system
At the first programming appointment, different electrode contacts and stimulation settings are tested.
The team assesses symptoms such as:
Tremor
Rigidity
Slowness
Dyskinesia
Walking
Speech
Stimulation-related side effects
Amplitude, pulse width, frequency and active contacts can be adjusted. Several programming visits may be required to find the best balance between symptom control and side effects.
Read Recovery and Programming After DBS Surgery for a closer look at this stage.
Is DBS brain surgery reversible?
DBS does not intentionally destroy brain tissue in the way that lesion procedures do. Stimulation can be switched off, and the system can be removed if medically necessary.
However, implantation is still brain surgery. Removal does not mean that every surgical effect or complication would automatically be reversed.
Frequently asked questions
Is the patient always awake during DBS surgery?
No. DBS may be performed awake, asleep or using a combination of anaesthetic approaches. The appropriate method depends on the patient and the centre’s protocol.
Are the wires visible after surgery?
No. The electrodes, extension wires and pulse generator are implanted beneath the skin. Small contours may sometimes be felt or seen under thin skin.
Is the battery placed inside the brain?
No. The electrodes are placed in the brain, while the pulse generator is usually positioned beneath the skin near the collarbone.
Does the device work as soon as it is implanted?
Not necessarily. Formal activation and programming commonly occur after an initial healing period. Several adjustments may be needed.
How large are the openings in the skull?
The electrodes are inserted through small burr holes rather than a large opening of the skull. The exact incision and opening depend on the surgical system and technique.
Conclusion
DBS is a planned treatment pathway rather than a single procedure. Careful patient selection, accurate imaging, individual target choice, precise electrode placement and postoperative programming all contribute to the outcome.
Patients considering surgery should understand both the implantation process and the continuing need for programming, medication review and long-term follow-up.
Kaan Tugberk Ozdemir, MDNeurosurgeon – Izmir, Türkiye
This article provides general information and does not replace an individual medical assessment, diagnosis or treatment recommendation.
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