But then we dove into this and why is it unsafe? And it's because of the side effects. Well, I think it's always important to challenge dogma in neuroscience and neurology, neurosurgery, and in particular, the dogma was that it was unsafe to do bilateral lesions. Now, let me ask you something: knowing the relevant side effects that there used to be with surgical, but other thalamotomies, what made you think that with focused ultrasound, things would be different - better? Actually in the paper, I really enjoyed also the discussion on the history of neuro functional interventions for tremor. Well, thank you very much for this overview of the past and current clinical options for treating essential tremor. And in this paper, we show that indeed it is possible to do bilateral surgery in a staged manner using focus ultrasound, and that the results are clinically very significant benefit and that the adverse effects are relatively minor and well-tolerated. And our paper really challenges that dogma, that bilateral surgery is not safe. The adverse effects can be quite high in the order of 30, 40, or 50% when it comes to speech disturbances, gait disturbances, paresthesias, weakness, et cetera.Īnd so until recently, people have been extremely reluctant to do bilateral lesion surgery. And until now, we know that there's a very high incidence of side effects if we were to treat tremor bilaterally, if you do bilateral thalamotomy or even bilateral DBS. Now, the difficulty is of course, and where the paper comes in, is that tremor affects both hands. And it is now the most common surgical procedure to treat tremor. And so because of that since 2012, for the last 10 years now, this technique has started to gain some influence and in fact is now the dominant technique to treat tremor of all surgical techniques. We focus them on the nucleus VIM, nucleus of the thalamus, and we get an instant result and we're able to adjust lesion in real time.Īnd we're able to get an effect that is immediate. We shoot ultrasound waves through the skull, usually about a thousand waves. And this has a number of interesting properties in that it is a non-invasive procedure. So the most recent addition to our toolbox has been the use of focused ultrasound. And that has certain advantages in that it's non-invasive, and yet, there's a delay in the clinical response and you're never quite sure that you've aimed in the right place. A third option is radiosurgery - that is to use gamma knife, for example, to noninvasively make a radio necrotic lesion and the thalamus. Then more recently, other operations have come into play, in particular deep brain stimulation is also quite effective for treating tremor and DBS has done exactly at the same target, and it has the advantage of being reversible and adjustable. And I was the oldest operation that was done. So a radio-frequency is usually the way that was done. And that involves making a Burr hole and introducing a needle and coagulating the neurons or the pathways that lead to colonic relay nucleus that causes tremor, the ventral intermediate nucleus. And the oldest operation is called a thalamotomy. We've had a number of surgical interventions historically for the last 50 to 70 years to treat tremor surgically. And it is for these patients that no longer respond or have intolerable side effects and are disabled by their tremor that we consider surgical intervention. Well, despite medications, about 40% of patients with essential tremor are disabled by their tremor. What options do we have and when do we need to think about them? Let me just start with the very basic question on the functional neurosurgery for essential tremor. Hello, Andreas, and welcome to the MDS podcast. This paper focuses on a recent technique, which is the MRI guided for use ultrasound for deep brain ablations, which has been used in the last few years, especially as a unilateral treatment for people with different kinds of tremor.

Disorders journal titled, 'Bilateral Focused Ultrasound Thalamotomy for Essential Tremor, Phase Two Trial.' He and his team have recently published an article in the Movement. Today, we will have the pleasure to interview professor Andres Lozano from the Division of Neurosurgery of the University of Toronto in Canada. I am Michele Matarazzo from the HM CINAC in Madrid, Spain. Welcome to the MDs podcast, the podcast channel of the International Parkinson and Movement Disorder Society.

Focused ultrasound for essential tremor