Your Brief Guide to Deep Brain Stimulation

With the recent media attention on Deep Brian Stimulation, more patients are questioning whether undergoing this procedure is something that will make a positive difference in their lives.  Here is your quick guide to DBS. 

What is Deep Brain Stimulation?

Deep Brian Stimulation (DBS) is a surgical procedure approved in the United States for over 15 years for treatment of Parkinson’s Disease (PD), Essential Tremor (ET), and Dystonia.  It is used specifically for the treatment of tremor, bradykinesia (slowness), rigidity (stiffness) and dyskinesia (levodopa induced abnormal/extra movements) in PD.  It is used to stop the tremor in ET patients.  The procedure itself involves a small lead that is inserted into the brain through a small hole in the skull.  Usually during this procedure the patient will remain awake as the clinical effects of this stimulation can be seen immediately in the operating room when the correct location for the lead has been reached.  The lead is positioned in one of two places for PD, the subthalamic nucleus (STN) or the globus pallidus internus (GPi), and for ET the lead is placed in the thalamus; usually GPi is used for the treatment of dystonia.  These different areas are nuclei in the brain that are thought to contribute to the pathology of each of these diseases.  While we know that the electrical stimulation that these leads deliver are helpful, we do not know the exact mechanism of how DBS works.  It is considered to be a “pacemaker” for the brain.  The exact location of the lead placement is decided upon prior to the surgery in conjunction with the neurosurgeon, the movement disorders specialist and the patient. 

After the lead has been inserted into the brain a wire is tunneled under the skin from the head to the chest where it is attached to a battery (IPG).  This battery will need to be replaced on average every 3-5 years.  Once implanted, it looks similar to a pacemaker battery. 

How soon do I see the effects?

Usually the DBS system will not actually be “turned on” or programmed until about 2-4 weeks after the initial brain surgery.  This is partly to wait for the reduction of swelling in the brain from the surgery in order to get a more accurate assessment at the programming session with your neurologist.  Sometimes we see a dramatic improvement in the few weeks immediately after surgery and then symptoms will slowly return.  This, again, has to do with the swelling in the brain and is from the actual lead placement itself.

Is deep brain stimulation right for me?

The answer to this question lies in the specifics of your own clinical picture.  To understand this, you must work closely with your movement disorders specialist.  In general, for PD, DBS only really helps symptoms such as bradykinesia, rigidity and dyskinesia.  We do not implant someone with DBS if gait and balance are main issues or if there are significant cognitive problems.  For this reason, everyone who is a DBS candidate must undergo neuropsychological testing prior to the surgery.  Neuropsychological testing is a 3-4 hour long process involving questions and activities that test many different domains of the brain.    It also assesses depression and anxiety to help us fully understand your full cognitive profile before putting you through brain surgery.  In the past there has been some evidence that DBS could potentially worsen gait/balance and/or cognition. 

For essential tremor, DBS becomes an option when you have tried multiple medications and either have no benefit from those medications or cannot continue to take more due to side effects.  Although the cognitive issues are certainly less with ET, most ET patients will also undergo neuropsychological testing prior to the surgery. 

Considering brain surgery can be scary and many people consider DBS a “last resort” therapy for PD, however, it really is not that.  You can pass a point in your PD where you are no longer a candidate for surgery due to gait/balance issues and cognitive issues as discussed above.  For most patients, DBS does make a huge difference in their lives: in the ability to move, in the reduction of dyskinesias and sometimes in the reduction of medications.  This surgery should be done at a large center by a neurosurgeon who is trained in this type of surgery.  If you are interested in DBS you should discuss it with your doctor earlier rather than later. 

 

How can I learn more?

You can check out NatGeo’s recent live DBS surgery at: http://channel.nationalgeographic.com/brain-surgery-live-with-mental-floss/videos/dbs-explained/

If you would like to learn more information about DBS, please attend the DBS Evening put together by PASB and sponsored by Medtronic on Thursday January 21, 2016 from 5:30-7:30pm at St. Andrew’s Church where you will be able to ask questions of patients who have had the procedure.  Dr. Kempe-Mehl and I will also be available to answer questions regarding DBS.  We would love to see you there!!!

-Dr. Erin Presant