Interview with Professor Andrea Kühn from the Charité, University Hospital in Berlin, Germany
The Charité University Medicine in Berlin is Europe’s largest university hospital and offers a comprehensive treatment spectrum at the forefront of medical care for patients from all over the world. One of the clinic’s focuses is the treatment of patients with movement disorders such as dystonia, Parkinson’s disease or essential tremor. Professor Kühn leads the movement disorders and neuromodulation unit at the department of neurology. For the treatment of dystonia patients, she has been working with the so-called Deep Brain Stimulation (DBS) and has achieved good results.
How long have you been working with DBS?
Professor Kühn: Deep Brain Stimulation (DBS) is a method that the Charité has been using since the late 90s to treat patients with Parkinson’s disease. Already in the year 2000, we have also operated our first patient with generalized dystonia. By now, DBS is a well-established treatment option and increases the patients’ quality of life by improving their ability to move. The Charité is broadly positioned in therapy and research, and besides DBS, also offers all other available treatment options for dystonia patients, also children.
How does DBS work?
Professor Kühn: Dystonia can be lead back to wrong regulations in brain circuits, namely information flow between the cerebral cortex and the basal ganglia (deep areas of the brain). DBS modulates neuronal activity in these areas by the use of high-frequency stimulation with 130 Hertz via deep brain electrodes that suppress the abnormal brain rhythms. Stimulation very successfully reduces involuntary movements in our patients. However, we are still investigating how exactly this works.
Who is suitable for a DBS therapy?
Professor Kühn: DBS is very effective for isolated dystonia and some forms of combined dystonia such as myoclonus-dystonia syndrome. Especially patients with severe generalised and cervical dystonia benefit from it. We also treat children from up to five years that suffer from genetically conditioned generalised dystonia. After the operation, these children can actively participate in life again.
What does the therapy look like?
Professor Kühn: DBS is teamwork, especially between neurologists and neurosurgeons. Only experienced neurosurgeons perform the operation. Under anaesthetic, two holes are drilled into the skull through which, depending on the size of the target area, electrodes with four to eight contacts are placed. These are connected to a stimulator that is implanted under the skin. Small, rechargeable stimulators last for up to 25 years and need to be charged about once a week via transmission. To reach an optimum effect of the therapy, the stimulator is set up and adjusted in the department of neurology.
What are the opportunities and risks of DBS?
Professor Kühn: The earlier we find the correct diagnosis and treatment is initiated, the higher the chances for beneficial outcome that allows the patient to benefit from the increased quality of life. The effect of DBS builds up slowly and gets more and more noticeable each month. Complications can occur during the surgery or through an infection. Possible side effects of the stimulation can be speech disorders and slower movement. Of course, we consult with every patients about all possible consequences before deciding for or against DBS.
How does the Charité act in this area of research?
Professor Kühn: In our research projects, we focus on neurophysiological measures of brain activity to better understand the reason why patients develop dystonia and how DBS acts to suppress involuntary movements. We are working to find biomarkers of the disease that can help to adjust DBS to individual needs by so-called adaptive, closed-loop stimulation. We also developed a software to localize the DBS electrodes after surgery that we use to find the best location for the stimulation.
The Charité is involved in different clinical trials that test DBS for isolated dystonia. Moreover, we aim to find out who else could benefit from DBS, e.g. patients that suffer from dystonia after brain damage.
To better understand dystonia and therefore offer better consultation for patients, we keep key data points of every patient in a multinational register study. The Charité also plays an active role in the dystonia network for rare diseases (DYSTRACT, headed by Prof. Volkmann/Prof. Klein) and there works together closely with other centres in Germany.