Dramatic improvement of truncal tardive dystonia following globus pallidus pars interna deep brain stimulation

Deep Brain Stimulation in the Treatment of Tardive Dyskinesia

Tardive dyskinesia (TD) is a phenomenon observed following the predominantly long-term use of dopamine receptor blockers (antipsychotics) widely used in psychiatry. TD is a group of involuntary, irregular hyperkinetic movements, mainly in the muscles of the face, eyelid, lips, tongue, and cheeks, and less frequently in the limbs, neck, pelvis, and trunk. In some patients, TD takes on an extremely severe form, massively disrupting functioning and, moreover, causing stigmatization and suffering. Deep brain stimulation (DBS), a method used, among others, in Parkinson's disease, is also an effective treatment for TD and often becomes a method of last resort, especially in severe, drug-resistant forms. The group of TD patients who have undergone DBS is still very limited. The procedure is relatively new in TD, so the available reliable clinical studies are few and consist mainly of case reports. Unilateral and bilateral stimulation of two sites has proven efficacy in TD treatment. Most authors describe stimulation of the globus pallidus internus (GPi); less frequent descriptions involve the subthalamic nucleus (STN). In the present paper, we provide up-to-date information on the stimulation of both mentioned brain areas. We also compare the efficacy of the two methods by comparing the two available studies that included the largest groups of patients. Although GPi stimulation is more frequently described in literature, our analysis indicates comparable results (reduction of involuntary movements) with STN DBS.

Long-term follow-up of bilateral subthalamic deep brain stimulation for refractory tardive dystonia

BACKGROUND

No effective treatment for tardive dystonia (TD) has been well established. Deep brain stimulation (DBS) can ameliorate motor manifestations in primary dystonia, and may also be an effective approach for TD.

OBJECTIVES

This study aimed to illuminate the long-term efficacy and safety of subthalamic nucleus (STN)-DBS in treating TD.

METHODS

Ten patients with refractory TD underwent STN-DBS therapy and were assessed by the Burke-Fahn-Marsden dystonia rating scale (BFMDRS), Abnormal Involuntary Movement Scale (AIMS), Hamilton Depression Scale (HAMD), Hamilton Anxiety Scale (HAMA), and the Short Form (36) Health Survey (SF-36) at four time points: pre-operation, 1 week post-operation, 6 months post-operation, and at a final long-term postsurgical follow-up time point.

RESULTS

The mean follow-up time was 65.6 ± 30.4 months (range, 12-105 months). At the first follow-up, BFMDRS motor and disability scores had improved by 55.9± 28.3% and 62.6± 32.0%, respectively, while AIMS scores improved by 53.3± 26.7%. At the second follow-up, BFMDRS motor and disability scores improved further, by 87.3± 17.0% and 84.3% ± 22.9%, respectively, while AIMS scores improved by 88.4 ± 16.1%. At the last follow-up, this benefit was sustained and had plateaued. Quality of life was improved significantly at the long-term follow-up, and the HAMA and HAMD scores displayed a significant reduction that persisted after the first follow-up.

CONCLUSION

STN-DBS may be an effective and acceptable procedure for TD, leading to persistent and significant improvement in both movement and psychiatric symptoms.

The phenomenology and treatment of idiopathic adult-onset truncal dystonia: a retrospective review

Background

Focal dystonia is the most common type of adult-onset dystonia; however, it infrequently affects truncal musculature. Although commonly attributed to secondary etiologies such as a neurodegenerative illness or tardive syndromes, the entity of idiopathic adult-onset truncal dystonia has only been previously described in a few case reports and small case series. Here we characterize seven cases of adult-onset primary truncal dystonia and present them within the scope of the existing literature.

Methods

Retrospective chart review of medical records and patient videos of seven adult patients with idiopathic truncal dystonia evaluated by the senior movement disorder neurologists in an urban outpatient clinic.

Results

The mean age of onset of idiopathic truncal dystonia was 47.6 years old and the majority of patients were male. Truncal flexion was the most common direction of dystonic movement and the dystonia was most frequently induced by action and could be improved by use of a sensory trick. The majority of patients were refractory to 3 or more oral treatments and only two patients exhibited significant functional improvement with botulinum toxin injections. One patient enjoyed significant benefit with bilateral internal globus pallidus deep brain stimulation.

Conclusions

Although a relatively rare presentation, patients with idiopathic adult-onset truncal dystonia can be identified by a common phenomenology. Diagnosis of this highly disabling condition is important because these patients are frequently refractory to multiple oral treatments and may benefit from early treatment with botulinum toxin or deep brain stimulation.

Electronic supplementary material

The online version of this article (doi:10.1186/s40734-016-0044-9) contains supplementary material, which is available to authorized users.

Therapeutic Perspective on Tardive Syndrome with Special Reference to Deep Brain Stimulation

Tardive syndrome (TDS) is a potentially permanent and irreversible hyperkinetic movement disorder caused by exposure to dopamine receptor blocking agents. Guidelines published by the American Academy of Neurology recommend pharmacological first-line treatment for TDS with clonazepam (level B), ginkgo biloba (level B), amantadine (level C), and tetrabenazine (level C). Recently, a class II study provided level C evidence for use of deep brain stimulation (DBS) of the globus pallidus internus (GPi) in patients with TDS. Although the precise pathogenesis of TDS remains to be elucidated, the beneficial effects of GPi-DBS in patients with TDS suggest that the disease may be a basal ganglia disorder. In addition to recent advances in understanding the pathophysiology of TDS, this article introduces the current use of DBS in the treatment of medically intractable TDS.

Functional gait disorder

Gait disorder is a common accompaniment of functional neurologic disorders. The diagnosis of a functional or psychogenic gait is complex. It requires a sound knowledge of the range of phenomenology observed in organic movement disorders, the ability to evaluate and diagnose nonmovement disorder neurologic symptoms and signs, but additionally knowledge of potential musculoskeletal causes of gait disturbance. A stepwise approach to the analysis of the phenomenology and separation into four (sometimes overlapping) psychogenic gait syndromes is suggested to aid diagnosis: (1) movement disorder mimics; (2) neurologic (nonmovement disorder) mimics; (3) musculoskeletal or biomechanical mimics; and (4) isolated disequilibrium or balance disorders. Accurate diagnosis can lead to effective therapy.

Uncommon applications of deep brain stimulation in hyperkinetic movement disorders

Background

In addition to the established indications of tremor and dystonia, deep brain stimulation (DBS) has been utilized less commonly for several hyperkinetic movement disorders, including medication-refractory myoclonus, ballism, chorea, and Gilles de la Tourette (GTS) and tardive syndromes. Given the lack of adequate controlled trials, it is difficult to translate published reports into clinical use. We summarize the literature, draw conclusions regarding efficacy when possible, and highlight concerns and areas for future study.

Methods

A Pubmed search was performed for English-language articles between January 1980 and June 2014. Studies were selected if they focused primarily on DBS to treat the conditions of focus.

Results

We identified 49 cases of DBS for myoclonus-dystonia, 21 for Huntington's disease, 15 for choreacanthocytosis, 129 for GTS, and 73 for tardive syndromes. Bilateral globus pallidus interna (GPi) DBS was the most frequently utilized procedure for all conditions except GTS, in which medial thalamic DBS was more common. While the majority of cases demonstrate some improvement, there are also reports of no improvement or even worsening of symptoms in each condition. The few studies including functional or quality of life outcomes suggest benefit. A limited number of studies included blinded on/off testing. There have been two double-blind controlled trials performed in GTS and a single prospective double-blind, uncontrolled trial in tardive syndromes. Patient characteristics, surgical target, stimulation parameters, and duration of follow-up varied among studies.

Discussion

Despite these extensive limitations, the literature overall supports the efficacy of DBS in these conditions, in particular GTS and tardive syndromes. For other conditions, the preliminary evidence from small studies is promising and encourages further study.