North Shore Private Hospital recently interviewed Visiting Medical Officer, Sydney DBS Neurologist Dr Paul Silberstein, and asked him how he got involved with Deep Brain Stimulation for Parkinson’s Disease and other movement disorders such as Dystonia, Tremor and Tourette Syndrome.
Why do you do what you do?
I have been interested in Neurology ever since my days as a medical student. I always liked the problem solving aspect of Neurology. As a Registrar, Movement Disorders caught my attention. I appreciated the strong reliance on clinical acumen, but also the therapeutic aspects. In the late nineties, we already had excellent pharmaceuticals for managing Parkinson’s Disease (PD) and Botulinum Toxin was already well established for Dystonia.
I was keen to pursue a Doctorate in Movement Disorders and was fortunate to be appointed to a Clinical Research Fellowship at the National Hospital for Neurology and Neurosurgery in London just as the Movement Disorder Surgery program was getting underway. I was astounded with the motor benefits the therapy could achieve in severely affected patients with PD, Dystonia and tremor disorders and have been committed to it ever since. About 75% of my practice is now related to Deep Brain Stimulation.
What are the challenges in managing Parkinson’s Disease (PD)?
PD is such a complicated condition. The motor aspects have been written about for decades, but it is only in the last 20 years that we have appreciated the prevalence and importance of non-motor aspects such as anxiety and depression, constipation, pain and in later disease postural hypotension and cognitive impairment.
We now know that non-motor symptoms, in particular Neuropsychiatric manifestations of PD have an even greater impact on quality of life than motor symptoms. Achieving patient engagement in management of non-motor symptoms, particularly neuropsychiatric symptoms can be a challenge, but is an integral part of good long term management.
What is Deep Brain Stimulation (DBS)?
Deep Brain Stimulation relates to the implantation of a cerebral neurostimulator that can be employed in the management of patients with Parkinson’s Disease, tremor disorders, Dystonia and Tourette’s syndrome when satisfactory symptom control cannot be achieved with optimal medical therapy.
Stimulating wires are implanted by a neurosurgical team in specific deep brain structures. These wires are routed under the skin to an implanted battery in the chest or abdominal wall. The battery produces a continuous impulse to the brain and provides 24-hour therapy to alleviate symptoms.
Who might benefit from DBS?
In Dystonia, tremor and Tourette’s syndrome, the main indication for surgery is failure to achieve satisfactory control with maximal medical therapy.
Patients with idiopathic Parkinson’s disease usually achieve good symptom control with medical therapy for a period of years. Over time, symptom control can however become progressively inconsistent (motor fluctuations) and sometimes accompanied by periods of excessive movement (dyskinesia). Medication adjustments can be effective in the short to medium term in ironing out motor fluctuations and dyskinesia. With time however, some patients find that consistent symptom control can no longer be achieved. DBS can be very effective in re-establishing motor consistency in this instance.
A small proportion of our work relates to patients with PD that have medication refractory tremor. These patients may opt to have surgery in the early years of their PD. Occasionally we also perform DBS on patients who are simply intolerant of all PD medications. This situation is uncommon but does occur.
What are the benefits of DBS?
In Parkinson’s disease, DBS smooths motor fluctuations, reduces dyskinesias by ~75% and facilitates reduction in anti-PD medications by 50-75%.
Essential tremor patients generally achieve 50-80% reduction in tremor. 50% of patients with Dystonia achieve >50 % reduction in Dystonia.