Deep Brain Stimulation (DBS) in Tourette Syndrome

In a small number of people with Tourette Syndrome (TS) tics can be so severe and extreme that the available treatment options, behavioural interventions and/or medication, offer little reduction in the severity of tics. Often these patients also present with behavioural problems, such as attention deficit hyperactivity disorder (ADHD), obsessive compulsive disorder (OCD), depression, anxiety, and self-injurious behaviours, so that their quality of life is significantly impaired. Neurosurgery called Deep Brain Stimulation (DBS) has been used on TS patients; however it is not currently available as a treatment on the NHS or in the private health sector in the UK. Other countries do offer DBS to people with severe TS, and it has been previously clinically trialed in the UK.

DBS in Tourette Syndrome

Among the neurosurgical techniques, deep brain stimulation (DBS) with implantation of electrodes at selected targets undoubtedly offers advantages over traditional surgery, which is more invasive and irreversible. DBS was first tried in TS in 1999 and consists of a procedure whereby stimulating electrodes are implanted in deep brain structures and connected through a wire to a pace-maker, which can be positioned under the skin of the chest.

Overall, DBS provides continuous electrical stimulation of specific brain structures, thereby selectively modulating the activity of these regions, while avoiding widespread adverse effects by affecting other uninvolved circuits. In patients with TS the most commonly selected stimulation targets are two brain areas called “thalamus” and “globus pallidus”. In addition to these regions, there are other possible targets, mainly within the striato-thalamo-cortical circuitry, which is considered to be dysfunctional in TS.

At the present time, DBS in TS is still in its infancy. Although preliminary studies are showing promising results in terms of tic reduction, there are still a number of question marks about the optimal targets and the suitable candidates. Moreover, the long-term effects of DBS on other aspects of TS (such as OCD, aggression, impulsivity, depression and anxiety) need more research.

It has to be noted that the surgical procedure carries risks of complications (including fatality) and the continuing stimulation can have side effects. An analysis of the existing literature shows that in the majority of cases patients after surgery still need pharmacological medication, albeit with dosages significantly reduced. These and other important issues can only be addressed by future collaborative trials on sufficiently large samples of patients.

More information

Websites

• University of Virginia Medical Center - images and descriptions about the DBS process.

Case studies/case series

• Okun MS, Foote KD, Wu SS, Ward HE, Bowers D, Rodriguez RL, Malaty IA, Goodman WK, Gilbert DM, Walker HC, Mink JW, Merritt S, Morishita T, Sanchez JC. A trial of scheduled deep brain stimulation for Tourette syndrome: moving away from continuous deep brain stimulation paradigms. JAMA Neurol. 2013 Jan;70(1):85-94.
• Ackermans L, Duits A, van der Linden C, Tijssen M, Schruers K, Temel Y, Kleijer M, Nederveen P, Bruggeman R, Tromp S, van Kranen-Mastenbroek V, Kingma H, Cath D, Visser-Vandewalle V. Double-blind clinical trial of thalamic stimulation in patients with Tourette syndrome. Brain. 2011 Mar;134(Pt 3):832-44.
• Porta M, Brambilla A, Cavanna AE, Servello D, Sassi M, Rickards H, Robertson MM. Thalamic deep brain stimulation for treatment-refractory Tourette syndrome: two-year outcome. Neurology. 2009 Oct 27;73(17):1375-80.
• Servello D, Porta M, Sassi M, Brambilla A, Robertson MM. Deep brain stimulation in 18 patients with severe Gilles de la Tourette syndrome refractory to treatment: the surgery and stimulation. J Neurol Neurosurg Psychiatry. 2008 Feb;79(2):136-42.
• Maciunas RJ, Maddux BN, Riley DE, Whitney CM, Schoenberg MR, Ogrocki PJ, Albert JM, Gould DJ. Prospective randomized double-blind trial of bilateral thalamic deep brain stimulation in adults with Tourette syndrome. J Neurosurg. 2007 Nov;107(5):1004-14.
• Vandewalle V, van der Linden C, Groenewegen HJ, Caemaert J. Stereotactic treatment of Gilles de la Tourette syndrome by high frequency stimulation of thalamus. Lancet. 1999 Feb 27;353(9154):724.

Guidelines

• Porta M, Cavanna AE, Zekaj E, D'Adda F, Servello D. Selection of patients with Tourette syndrome for deep brain stimulation surgery. Behav Neurol. 2013;27(1):125-31.
• Piedad JC, Rickards HE, Cavanna AE. What patients with gilles de la tourette syndrome should be treated with deep brain stimulation and what is the best target? Neurosurgery. 2012 Jul;71(1):173-92.
• Müller-Vahl KR, Cath DC, Cavanna AE, Dehning S, Porta M, Robertson MM, Visser-Vandewalle V; ESSTS Guidelines Group. European clinical guidelines for Tourette syndrome and other tic disorders. Part IV: deep brain stimulation. Eur Child Adolesc Psychiatry. 2011 Apr;20(4):209-17.
• Cavanna AE, Eddy CM, Mitchell R, Pall H, Mitchell I, Zrinzo L, Foltynie T, Jahanshahi M, Limousin P, Hariz MI, Rickards H. An approach to deep brain stimulation for severe treatment-refractory Tourette syndrome: the UK perspective. Br J Neurosurg. 2011 Feb;25(1):38-44.
• Porta M, Sassi M, Ali F, Cavanna AE, Servello D. Neurosurgical treatment for Gilles de la Tourette syndrome: the Italian perspective. J Psychosom Res. 2009 Dec;67(6):585-90.
• Mink JW, Walkup J, Frey KA, Como P, Cath D, Delong MR, Erenberg G, Jankovic J, Juncos J, Leckman JF, Swerdlow N, Visser-Vandewalle V, Vitek JL; Tourette Syndrome Association, Inc. Patient selection and assessment recommendations for deep brain stimulation in Tourette syndrome. Mov Disord. 2006 Nov;21(11):1831-8.