DBS Surgery Explained
Learn more about Deep Brain Stimulation Surgery.
The Stages of
DBS involves keyhole brain Neurosurgery. After a burr hole, about the size of a 10c piece is made in the skull, a tiny incision is made in the lining of the brain to allow implantation of the stimulating electrode.
The actual surgical target generally lies 7-8 cm into the brain, and is not seen directly by the Neurosurgeon.
Accordingly, DBS surgery is like landing a plane at night in a dense fog. The runway can’t be seen and the landing must be managed through the use of computational instruments.
Modern DBS utilises a variety of advanced computational instruments to achieve surgical accuracy including sophisticated neurosurgical equipment and navigation software, intraoperative devices for recording from and stimulating the brain and intra-operative x-ray.
Stereotactic Frame Application
Firstly, the surgical frame is attached to the skull. This is performed in a seated position, under light sedation. Generally patients have very little recollection of this stage of the procedure.
With the frame in place, patients then undergo a CT scan. These images are then fused using BrainLab neuro-navigation software to MRI images obtained within the week prior to surgery.
These fused images are then used for surgical planning, so that the patient’s own brain becomes the map for computational planning of their procedure.
Surgical planning is then performed in the operating theatre using neurosurgical navigation software. This allows planning of the target and trajectory of electrode implantation.
Specifically, the software allows three dimensional tracking of the probe through the brain, maximising accuracy and minimising risk.
Electrode implantation is most commonly performed under local anaesthetic and light sedation. This allows electrical recording and test stimulation to be performed during the operation itself. Brain activity mapping and effects of test stimulation are two important means of confirming surgical accuracy. The use of light sedation makes it possible for patients to be briefly but safely and comfortably woken up for these important stages of the operation.
Once surgical planning is completed, Dr Cook determines the position of the scalp incision, programs the Stereotactic frame, and drills the burr hole through the skull.
This hole made in the skull is about the size of a 10cm piece. A tiny hole is then made in the lining of the Brain allowing passage of the testing microelectrode. This electrode has dual functionality, allowing direct recording of Brain activity as well as test electrical stimulation. Dr Cook utilises a Microdrive mounted on the sterotactic frame to implant this electrode.
Connection of the Stimulating Electrode to the Stimulating Battery
The final stage of the operation involves the attachment of the fixed brain electrodes to the stimulator battery via a connector wire, and then implantation of the battery in the chest or abdominal wall.
This stage of the surgery is performed under a general anaesthetic.
The connector lead is tracked under the skin of the right side of the neck and then attached to the brain electrodes just above and behind the right ear.
The stimulator battery is then attached to the connector wire and then implanted under the skin of the chest or abdomen and the wound closed
After surgery, the patient is transferred to the intensive care unit for overnight observation.
A cerebral CT scan is performed post operatively as a routine. Dr Silberstein adjusts Parkinson’s medication.
In most patients, stimulation is commenced on the evening following surgery. Patients are transferred to the Neurosurgical Ward the following morning.
Most patients are ambulant within 24-48 hours of surgery, depending on pre-surgical status.