What is Deep Brain Stimulation?
Deep Brain Stimulation (DBS) is a treatment for selected patient suffering from Parkinson’s disease dystonia and most forms of tremors. Recently, the use of DBS therapy has been extended for the treatment of intractable epilepsy, refractory Obsessive compulsive disorders, depression and Progressive supranuclear palsies.
DBS consist of implantation of very thin DBS Lead which contains four electrode contacts into the target area in the brain. The lead extends through a small opening in the skull and is connected to the extension that is then connected to an impulse generator or pacemaker which is implanted under the skin over the chest. The entire system is implanted beneath the skin. DBS exerts its therapeutic effect by delivering electrical impulses to the target region.
Deep Brain Stimulation is an alternative to ablative surgeries conventionally offered for Parkinson’s disease and other related movement disorders. The common targets for DBS surgery within the brain, for movement disorder include, subthalamic nucleus (STN) for Parkinson’s disease, ventro-intermedius nucleus of thalamus for tremors, and pallidum for dystonia. Though each of this target sites can be used for different movement disorder, we believe that these are best for the respective disease as indicated.
The therapy of Deep Brain Stimulation requires additional expertise over conventional stereotactic techniques that are required for functional neurosurgical procedures for movement disorder. It requires careful understanding of the principles of DBS, understanding of the disease being treated and combining the medical therapy along with stimulation to achieve smooth control of the disease
Deep brain stimulation involves the implantation of a wire, with 4 electrodes at its tip, into one of 3 target sites in the brain:
• The thalamus (this procedure is known as thalamic stimulation)
• The globus pallidus (this procedure is pallidal stimulation)
• The subthalamic nucleus (this procedure is subthalamic stimulation)
• Thalamic Deep Brain Stimulation - In Thalamic deep brain stimulation, the DBS electrode is placed down into the thalamus and testing is begun. Electrical impulses are sent from the tip of the electrode into the thalamus. This is to identify a brain location where the tremor can be stopped effectively. At the same time, the surgical team monitors for any side effects of stimulation like numbness of the face, mouth, heaviness or weakness of the limb, change in speech, etc. If good results are obtained, the electrode is left in place and anchored to a plastic clip that is attached to the skull opening. The wound is then closed.
In stage two of the operation, the patient is given a general anesthetia and put to sleep. The side of the head, neck and upper chest is prepared and draped. A small incision is made below the collarbone to allow creation of a small pouch underneath the skin that will hold the stimulator pulse generator or battery. A small incision is made behind the ear and a cable passed from the chest incision up to the head (all under the skin). This cable is then attached to the electrode coming out of the brain using a small plastic cover. The entire system remains underneath the skin. Generally, the chest incision is closed with an invisible stitch that does not need to be removed. The scalp stitches (in the front and behind the ear) are closed with nylon.
• Subthalamic Deep Brain Stimulation - This procedure is similar. However, once the skull opening has been created safely, a microelectrode (very small metal wire) is inserted into the brain toward the thalamus and subthalamic region. A neurophysiologist participates in the identification of specific brain cells in these regions. The purpose is to map out the area optimize placement of the electrode. Often the room will be dark during this time period. The patient will be kept comfortable during this time as the brain is evaluated. The time for microelectrode recording can take several hours. Once the appropriate area is identified, test stimulation is performed in order to check that the electrode is in a safe location that will not disturb brain function. When the safe area is identified, the electrode will be left in place and clipped to the skull bone-fastening device. If both sides of the brain are to be operated on at the same setting, a second incision will be made on the other side and the procedure repeated. This will again take several hours.
Subthalamic deep brain stimulation is a longer operation. For most patients, the first stage of the operation which is placing electrodes into the brain will be performed in one day. The patient will be observed overnight in the hospital. The scalp incisions will be closed and the patient will return to the hospital 3-7 days later for the second stage of the procedure. At the second stage, performed under a general anesthetic, the cables and batteries will insert into the neck and chest area. Once the device is inserted, the patient will return to the neurology clinic. The stimulators will be turned on by the neurologist and his team several weeks later.
• Globus Pallidus Deep Brain Stimulation - The procedure is similar to that described above with several exceptions. In dystonia patients, the electrodes are placed into the brain using MRI stereotactic guidance, and then checked using stimulation. For most patients, both electrode insertion under local anesthesia and cable and pulse generator placement under general anesthesia is performed on the same day.
DBS is a surgical option that is known to improve quality of life for movement disorder patients, so when one’s quality of life is dramatically affected by the disease or by medication side effects, it’s time to consider DBS. Following are the conditons where Deep Brain Stimulation Surgery can be performed:
Parkinson Disease: DBS surgery offers important symptomatic relief in patients with moderate disability from Parkinson's disease who still retain some benefit from antiparkinsonian medications and who are cognitively intact. Patients who fluctuate between "ON” and “OFF” medication states are usually good surgical candidates, as are those who have troublesome dyskinesias.
Dystonia: DBS surgery does not cure dystonia but can decrease the abnormal movements and postures of dystonia. The degree of benefit appears to vary with both the type of dystonia and the duration of the symptoms. Adolescents and young adults with inherited forms of primary dystonia appear to get very significant benefit. For patients with secondary dystonia due to stroke or head trauma, the benefit may be mild. Adults who have had dystonia for many years probably have less improvement than those with more recent onset of symptoms.
Essential Tremor: DBS is a highly effective therapy for patients with essential tremor, often resulting in an 80% decrease in tremor that lasts for several years. Patients with a tremor secondary to stroke, traumatic brain injury or multiple sclerosis are less likely to benefit from DBS.
Deep brain stimulation therapy offers a number of advantages. The electrical stimulation is adjustable, whereas surgical destruction is not. As the patient's response to surgery changes over time, the stimulation can be adjusted without the necessity of repeat operation.
Another significant advantage of deep brain stimulation therapy relates to future treatments. Destructive surgery, such as thalamotomy or pallidotomy, may reduce the patient's potential to benefit from future therapies. For example, future brain cell transplantation may be of great help to patients with Parkinson's disease. There is concern that a pallidotomy or thalamotomy may prevent patients from benefiting from brain cell transplantation. This would not be the case with deep brain stimulation as the stimulator could be turned off. Studies show that in 65-85% of the people who have been implanted with the Deep Brain Stimulation system, the treatment has significantly reduced, if not eliminated, their tremor. In fact, the vast majority of recipients report being able to participate in activities, they could not even attempt before treatment.
DBS therapy has become a much known therapy to mitigate movement related disorders but can have serious repercussions if not delivered by an experienced, knowledgeable and skilled specialist. In India most of the surgeons, doctors and health care professionals are internationally trained. These professionals have handled multiple cases related to Deep Brain Stimulation Therapy.
There are millions of people who travel each year to India for different types of medical and surgical procedures. They seek medical and surgical treatment in India as these facilities are either very expensive or unavailable in their own country especially an advanced brain stimulation therapy like DBS. Indian hospitals have become highly popular for their state-of-the-art amenities and sophisticated infrastructure. There are many hotels of international standards that make accommodation easy for those who seek medical and surgical treatment in India. Travelling in India has become easier as modes of transportation have increased dramatically. That is why many people fro.