A surgical technique that sends electrical impulses to a specific area of the brain reduces the 鈥渢ics,鈥 or involuntary movements and vocal outbursts, experienced by young adults with severe cases of Tourette syndrome, according to a new study led by investigators from 嘿嘿视频 Medical Center.
The study, in the Journal of Neurosurgery, is a retrospective review of patients with Tourette syndrome who underwent an experimental technique known as thalamic deep brain stimulation (DBS) at 嘿嘿视频. The findings, according to the researchers, add to a growing body of evidence supporting DBS as a safe and effective treatment for severe cases of Tourette syndrome鈥攁nd may ultimately lead to approval by the United States聽Food and Drug Administration (FDA).
鈥淥ur study shows that deep brain stimulation is a safe, effective treatment for young adults with severe Tourette syndrome that cannot be managed with current therapies,鈥 says Alon Mogilner, MD, PhD, an associate professor in the departments of and at 嘿嘿视频, and director of its Center for Neuromodulation. 鈥淭his treatment has the potential to improve the quality of life for patients who are debilitated through their teenage years and young adulthood.鈥
Tourette syndrome begins in childhood and many patients improve as they get older. However, for some, the symptoms become so severe that they become socially isolated and unable to work or attend school.
Dr. Mogilner and his colleague, Michael H. Pourfar, MD, an assistant professor in the departments of Neurosurgery and and co-director of the Center for Neuromodulation, have pioneered the largest U.S. case series of thalamic DBS to treat severe Tourette syndrome in young adults. Worldwide, only an estimated 160 cases have been performed to date.
In a multistage procedure, the doctors insert two electrodes into a region of the brain called the medial thalamus, part of the brain circuit that functions abnormally in people with Tourette syndrome. During a second surgery the following day or a few days later, a pacemaker-like device called a neurostimulator is connected to the electrodes to emit electrical impulses into the medial thalamus. These impulses are adjusted during a series of follow-up outpatient visits to find the combination of settings that best control symptoms.
In the study, the 嘿嘿视频 team followed 13 patients with at least 6 months of follow-up visits. Study participants ranged in age from 16 years to 33 years. To determine the effectiveness of the procedure, the researchers measured the severity of tics before and after surgery using the Yale Global Tic Severity Scale (YGTSS). They found that the severity of tics decreased, on average, 37 percent from the time of the operations to the first follow-up visit. At their latest visit, patients鈥 tic scores decreased by an average of 50 percent.
Equally significant, all patients reported in a survey six months after surgery that their symptoms improved either 鈥渕uch鈥 or 鈥渧ery much,鈥 and all said they would have the surgery again鈥攅ven those who had complications or experienced relatively less pronounced responses. 鈥淭he survey represents an important aspect of the study,鈥 Dr. Pourfar says, 鈥渂ecause the YGTSS, though a validated scale, may not fully capture the impact of DBS on quality of life for a person with Tourette syndrome.鈥
Since the study completed, four more patients have undergone DBS surgery for Tourette syndrome.
DBS has been used to treat other neurological conditions that cannot be adequately controlled by medication, including Parkinson鈥檚 disease, essential tremor, dystonia, and epilepsy.
Because the FDA has not yet approved DBS for the treatment of Tourette syndrome, it is still considered investigational. As a result, a committee of independent specialists reviews each case to ensure that patients have tried alternate therapies and that the disability is severe enough to warrant undergoing the procedure.
In addition to Drs. Mogilner and Pourfar, Richard S. Dowd, MD, of Tufts Medical Center served as a co-author.
Dr. Pourfar reports receiving consulting fees and teaching honoraria from Medtronic Neurological, the manufacturer of the DBS device used in the study. Dr. Mogilner reports receiving consulting fees, honoraria, and grant support from Medtronic Neurological, and consulting fees from Alpha-Omega Engineering.
