Bilateral globus pallidus internus deep brain stimulation in tardive dyskinesia: a case report.

The clinical response of a 53-year-old woman with tardive dyskinesia treated with bilateral globus pallidus interna deep brain stimulation is described. At 18 months follow-up, her Burke-Fahn-Marsden Dystonia Rating Scale score fell from 52 (preoperative) to 21 (60% improvement).     

Deep brain stimulation in dystonia: Sonographic monitoring of electrode placement into the globus pallidus internus

Deep brain stimulation (DBS) of the globus pallidus internus (GPi) is an effective treatment in primary dystonia. Its success depends on the implantation accuracy of the DBS electrode into the targeted GPi. Discrepancies of up to 4 mm between the initial target, selected on preoperative MRI, and the final DBS lead location are caused mainly by caudal brain shift that occurs once the cranium is open. Nowadays, transcranial sonography (TCS) can display echogenic deep brain structures with higher image resolution compared to MRI under clinical conditions. Here, we demonstrate for the first time the use of a contemporary clinical high‐end TCS system for intraoperative monitoring of DBS electrode position. Herewith, a high‐resolution real‐time imaging of closely located microelectrodes and of the DBS lead through the intact skull is feasible. Simultaneous color‐coded sonographic imaging of arteries near the anatomical target allows further intraoperative refinement of DBS lead positioning, simultaneously preventing hemorrhages. © 2009 Movement Disorder Society     

Unilateral deep brain stimulation of the internal globus pallidus alleviates tardive dyskinesia.

We describe a patient with fluspirilene-induced tardive dyskinesia of the choreiform oro-facial-laryngeal type resistant to various conservative approaches for 7 years who underwent deep brain stimulation of the internal pallidal globe. We found immediate and marked suppression of her perioral involuntary movements with unilateral stimulation at 60 Hz.     

Globus pallidus internus versus subthalamic nucleus deep brain stimulation for isolated dystonia: A 3-year follow-up

Background and purpose

Bilateral deep brain stimulation (DBS) surgery targeting the globus pallidus internus (GPi) or the subthalamic nucleus (STN) is widely used in medication-refractory dystonia. However, evidence regarding target selection considering various symptoms remains limited. This study aimed to compare the effectiveness of these two targets in patients with isolated dystonia.

Methods

This retrospective study evaluated 71 consecutive patients (GPi-DBS group, n = 32; STN-DBS group, n = 39) with isolated dystonia. Burke–Fahn–Marsden Dystonia Rating Scale scores and quality of life were evaluated preoperatively and at 1, 6, 12, and 36 months postoperatively. Cognition and mental status were assessed preoperatively and at 36 months postoperatively.

Results

Targeting the STN (STN-DBS) yielded effects within 1 month (65% vs. 44%; p = 0.0076) and was superior at 1 year (70% vs. 51%; p = 0.0112) and 3 years (74% vs. 59%; p = 0.0138). For individual symptoms, STN-DBS was preferable for eye involvement (81% vs. 56%; p = 0.0255), whereas targeting the GPi (GPi-DBS) was better for axis symptoms, especially for the trunk (82% vs. 94%; p = 0.015). STN-DBS was also favorable for generalized dystonia at 36-month follow-up (p = 0.04) and required less electrical energy (p < 0.0001). Disability, quality of life, and depression and anxiety measures were also improved. Neither target influenced cognition.

Conclusions

We demonstrated that the GPi and STN are safe and effective targets for isolated dystonia. The STN has the benefits of fast action and low battery consumption, and is superior for ocular dystonia and generalized dystonia, while the GPi is better for trunk involvement. These findings may offer guidance for future DBS target selection for different types of dystonia.     

Deep brain stimulation of the internal globus pallidus for refractory tardive dystonia

We report a rapid, dramatic and sustained improvement following bilateral pallidal stimulation in two patients affected by intractable generalized tardive dystonia. Both patients had a chronic psychiatric disorder and developed chronic disabling generalized dystonic symptoms persisting despite prolonged withdrawal of neuroleptics and all available symptomatic treatment. The clinical benefit in both patients persisted throughout all the follow up period of 13 and 7 months. The favorable and prolonged response in our two patients suggests that deep brain stimulation may be an effective treatment for medically refractory tardive dystonia.     

Therapy‐refractory tourette syndrome: Beneficial outcome with globus pallidus internus deep brain stimulation

We report on a female patient with Tourette syndrome and a 12‐month follow‐up after chronic deep brain stimulation in the globus pallidus internus which resulted in excellent remission of motor and vocal tics. © 2008 Movement Disorder Society     

Globus pallidus deep brain stimulation in dystonia.

Globus pallidus deep brain stimulation (GPi-DBS) is a useful alternative in the treatment of dystonia. Patients selected for GPi-DBS were prospectively rated with the Unified Dystonia Rating Scale (UDRS). Also, "blinded" videotape assessments were performed. Eleven patients were identified. Compared with pre-DBS scores, there were improvements in mean total UDRS score (15.3%) and in the following subscores: neck (18.18%), trunk (32.9%), arm (17.9%), and leg (19.9%). One patient developed a skin infection and erosion requiring surgical debridement. GPi-DBS is a safe and effective treatment for generalized dystonia in patients who remained impaired, despite optimal medical therapy.     

Complete suppression of paroxysmal nonkinesigenic dyskinesia by globus pallidus internus pallidal stimulation.

Stereotactic functional surgery is being explored as potential therapies for medically intractable paroxysmal dyskinesias (PxD). We report on a 59-year-old man in whom stimulation of globus pallidus internus produced immediate and sustained relief of paroxysmal non-kinesigenic dyskinesia secondary to a rotator cuff tears on the left shoulder. Our finding strongly suggests that altered function of neuronal circuits of the basal ganglia underlies the manifestation of PxD.     

Battery lifetime in pallidal deep brain stimulation for dystonia

Background and Purpose: The aim of the study was to analyse the lifetime of Soletra implantable pulse generators (IPG) in deep brain stimulation (DBS) of the globus pallidus internus (GPi) for dystonia, depending on stimulation parameters and the total electrical energy delivered (TEED) by the IPG. Methods: In a prospective series of 20 patients with GPi DBS for dystonia, we recorded IPG longevity and stimulation parameters over time. An evaluation of the TEED was performed using the previously suggested equation [(voltage² × pulse width × frequency)/impedance] × 1 s. Results: During median follow‐up of 57 months (range 23–79 months), 64 IPGs were replaced because of battery depletion or end of life signal. We found a mean IPG longevity of 25.1 ± 10.1 (range 16–60) months, which was inversely correlated with the TEED (r = −0.72; P < 0.001). IPG longevity was not different between bipolar and monopolar stimulation (24.9 ± 10.8 vs. 25.4 ± 9.0 months, P = 0.76). Incongruously, the mean TEED applied throughout the lifetime cycle was significantly higher in patients with bipolar compared with monopolar stimulation (584 ± 213 vs. 387 ± 121 Joule; P < 0.01). Conclusions: Battery lifetime in GPi DBS for dystonia is substantially shorter compared with that reported in DBS for Parkinson’s disease, caused by a considerably higher voltage and greater pulse width and therefore a higher TEED applied during the battery lifetime cycle. The commonly used equation to calculate TEED, however, seems to be correct only for monopolar, but not bipolar stimulation.     

Stimulation of the globus pallidus internus for childhood-onset dystonia.

We report the results of deep brain stimulation (DBS) of the globus pallidus internus (GPi) in 12 patients with childhood-onset generalized dystonia refractory to medication, including 3 patients with status dystonicus. There were 8 patients who had DYT1-negative primary dystonia, 1 had DYT1-positive dystonia, and 3 had symptomatic dystonia. Stimulation was effective in all but 1 patient. Dystonic postures and movements of the axis and limbs responded to DBS to a greater extent than oromandibular dystonia and fixed dystonic postures. These findings provide further evidence that pallidal stimulation is an effective treatment for intractable childhood-onset dystonia, including status dystonicus, and together with previous findings, suggest that it should be considered the treatment of choice for these conditions.     

Pallidal stimulation in cervical dystonia: clinical implications of acute changes in stimulation parameters

Background and purpose:  Deep brain stimulation (DBS) of the globus pallidus internus (GPi) is successful in dystonia, but the role of each electrical parameters of stimulation is unclear. We studied the clinical effects of acute changes of different parameters of GPi–DBS in cervical dystonia (CD).
Methods:  Eight CD patients with bilateral GPi–DBS at 28.6 ± 19.2 (mean ± SD) months after surgery were recruited. Mean improvement in the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) severity score was 54.5% compared to before surgery. Ten settings, including a combination of a wide range of pulse widths (PWs), low and high frequencies and voltage, were administered in a randomized double blinded fashion. Clinical benefit was assessed by two raters using the TWSTRS and by the patients using an analogue rating scale.
Results:  The TWSTRS severity scores were reduced by 56.7% with stimulation at the best settings. Improvement was significantly associated with high frequency (≥60 Hz) and high voltage. Stimulation at 130 Hz showed the best clinical improvement. Increasing PWs (from 60 to 450 μs) did not result in a significant improvement.
Conclusion:  Frequency and amplitude appear to be the most important factors in the acute anti-dystonic effects in GPi–DBS patients with CD.     

Chronic high-frequency globus pallidus internus stimulation in different types of dystonia: a clinical, video, and MRI report of six patients presenting with segmental, cervical, and generalized dystonia.

The results of deep brain stimulation (DBS) of the globus pallidus internus (Gpi) in six patients with generalized, focal, and segmental dystonia are presented. Pre- and postoperative assessments are given for one patient with generalized inherited dystonia and for five patients with idiopathic segmental or cervical dystonia. Clinical symptoms were evaluated before and 3-12 months after surgery using the Burke-Fahn-Marsden (BFM) dystonia rating scale for primary torsion dystonia and the Tsui scale for cervical dystonia. The Short-Form Health Survey (SF-36) was completed by each patient to document preoperative and postoperative health status. Also, neurological status was documented by video before and during chronic stimulation. Magnetic resonance imaging studies were performed to show the anatomical localization of the electrode leads. Five patients showed a progressive improvement within 7 days. One patient with cervical dystonia and Meige's syndrome showed no improvement for 3 months, but beneficial effects were observed after 12 months. On average, the BFM movement scale scores decreased by 72.5% and Tsui scale scores by 63%. SF-36 showed an improvement in health status by an average of 36% according to eight different health categories. We conclude that chronic high-frequency Gpi stimulation in different types of dystonia is a very effective and safe treatment.     

Pallidal and thalamic deep brain stimulation in myoclonus‐dystonia

Deep brain stimulation (DBS) of the internal globus pallidus (GPi) and ventral intermediate thalamic nucleus (VIM) are established treatment options in primary dystonia and tremor syndromes and have been reported anecdotally to be efficacious in myoclonus‐dystonia (MD). We investigated short‐ and long‐term effects on motor function, cognition, affective state, and quality of life (QoL) of GPi‐ and VIM‐DBS in MD. Ten MD‐patients (nine ε‐sarcoglycan‐mutation‐positive) were evaluated pre‐ and post‐surgically following continuous bilateral GPi‐ and VIM‐DBS at four time points: presurgical, 6, 12, and as a last follow‐up at a mean of 62.3 months postsurgically, and in OFF‐, GPi‐, VIM‐, and GPi‐VIM‐DBS conditions by validated motor [unified myoclonus rating scale (UMRS), TSUI Score, Burke‐Fahn‐Marsden dystonia rating scale (BFMDRS)], cognitive, affective, and QoL‐scores. MD‐symptoms significantly improved at 6 months post‐surgery (UMRS: 61.5%, TSUI Score: 36.5%, BFMDRS: 47.3%). Beneficial effects were sustained at long‐term evaluation post‐surgery (UMRS: 65.5%, TSUI Score: 35.1%, BFMDRS: 48.2%). QoL was significantly ameliorated; affective status and cognition remained unchanged postsurgically irrespective of the stimulation conditions. No serious long‐lasting stimulation‐related adverse events (AEs) were observed. Both GPi‐ and VIM‐DBS offer equally effective and safe treatment options for MD. With respect to fewer adverse, stimulation‐induced events of GPi‐DBS in comparison with VIM‐DBS, GPi‐DBS seems to be preferable. Combined GPi‐VIM‐DBS can be useful in cases of incapaciting myoclonus, refractory to GPi‐DBS alone. © 2010 Movement Disorder Society     

Interruption of deep brain stimulation of the globus pallidus in primary generalized dystonia

Stimulation (DBS) of the globus pallidus (GP) is effective to treat generalized dystonia. Little is known about the evolution of dystonia in case of arrest after a long period of stimulation. This study describes the course of dystonia during a 48 hours period without stimulation followed by a 24 hours period after turning ON the stimulator. 14 patients with generalized dystonia treated with bilateral GP DBS for 3 years or more were recruited. Blinded video‐based analysis was performed using Burke‐Fahn‐Marsden scale at (1) baseline (ON stimulation), (2) up to 48 hours after the stimulator was turned OFF, and (3) 24 hours after the stimulator was turned ON. 13 patients completed the 48 hours OFF‐stimulation period. The dystonia movement score progressively worsened from 24.3 ± 13.9 at baseline to 48.9 ± 19.8 after 48 hours (P < 0.00001). The disability score also worsened from 4.4 ± 1.2 at baseline to 5.7 ± 1.5 after 48 hours without stimulation (P < 0.001). When the neurostimulator was turned ON, the dystonia scores returned to baseline level after 10 hours. The interruption of GP DBS in dystonia results in a progressive worsening which is rapidly reversible once the neurostimulator is turned ON. © 2009 Movement Disorder Society     

Factors predicting improvement in primary generalized dystonia treated by pallidal deep brain stimulation

Despite the beneficial effects of Globus Pallidus internus (GPi) deep brain stimulation (DBS) in patients with primary generalized dystonia (PGD), the degree of improvement varies from one patient to another. The objective of this study was to examine the effects of clinical, anatomical (volume of the GPi), and electrical variables on the postoperative Burke‐Fahn‐Marsden Dystonia rating scale (BFMDRS) motor score to identify which factors may be predictive of the degree of improvement. We reviewed retrospectively the clinical records of 40 steady‐state patients with PGD who had been treated by bilateral GPi lead implantation. The follow‐up period was 2 to 8 years. The correlation between the electrical parameters (voltage, impedance, and current) and the clinical outcome was studied. An analysis of covariance was performed to identify factors predictive of the magnitude of improvement. The most influential factors according to the model are as follows: the preoperative BFMDRS score (P < 0.0001); age at surgery (P < 0.0001); the right GPi volume (P = 0.002); the left stimulated GPi volume (P = 0.005). No significant correlation was found between the electrical parameters used and the mean motor scores in steady state. © 2009 Movement Disorder Society     

Functional outcome and quality of life in Tourette's syndrome after deep brain stimulation of the posteroventrolateral globus pallidus internus: long-term follow-up

Objectives. Deep brain stimulation (DBS) for Tourette's syndrome (TS) in various targets has been in the focus for some years. However, there are hardly any data on “psychosocial” outcome after DBS for TS. The aim of the present study therefore was to focus on the functional outcome and “psychosocial changes” in TS patients after DBS. Methods. Six patients with treatment-refractory TS underwent GPi-DBS. The Yale Global Tic Severity Scale (YGTSS) was used to evaluate symptomatic outcome. Psychosocial changes were assessed applying the Global Assessment of Functioning Scale (GAF) and the Gilles-de-la-Tourette-Syndrome Quality-of-Life scale (GTS-QOL) with additionally documenting psychosocial changes. Follow-up ranged between 12 and 72 months. Results. In all symptomatic responders (4 of 6) we found a significant functional improvement (mean GAF increasing from 53.75 (± 7.5) pre-operatively to 83.75 (± 7.5) at last follow-up) along with a positive correlation with the course of GTS-QOL (R² = 0.62). Conclusions. Treatment success should not only be assessed with the classic “tic-scales”, but also with the GAF and GTS-QOL. Although improvement of tics seems to be positively correlated with improved functional outcome, symptomatic improvement may lead to unexpected major psychosocial changes – which both the patient and the clinicians in charge – should be prepared for.     

Changes in blink reflex excitability after globus pallidus internus stimulation for dystonia.

A pathophysiological feature of dystonia is reduced inhibition at various levels of the nervous system, which may be detected in clinically unaffected body parts. Chronic deep brain stimulation (DBS) of the globus pallidus internus (GPi) has emerged as an effective treatment for primary torsion dystonia (PTD), although its mechanism of action and impact on inhibitory abnormalities in dystonia are unknown. We sought to understand the effect of GPi DBS on brainstem excitability in patients with PTD. We measured the blink reflex from orbicularis oculi in response to paired electrical stimulation of the supraorbital nerve at interstimulus intervals of 500 and 1,000 milliseconds in 10 patients with PTD before and at intervals of 1, 3, and 6 months after bilateral GPi DBS and in 10 healthy subjects. Patients were clinically evaluated using the Burke-Fahn-Marsden dystonia rating scale. We found R2 inhibition was significantly decreased in PTD patients compared with control subjects and progressively increased after GPi DBS, which correlated with clinical improvement in dystonia. We conclude that GPi DBS for PTD results in functional reorganization of the nervous system, which includes a long-term increase in brainstem inhibition.