TorsinA restoration in a mouse model identifies a critical therapeutic window for DYT1 dystonia.

In inherited neurodevelopmental diseases, pathogenic processes unique to critical periods during early brain development may preclude the effectiveness of gene modification therapies applied later in life. We explored this question in a mouse model of DYT1 dystonia, a neurodevelopmental disease caused by a loss-of-function mutation in the TOR1A gene encoding torsinA. To define the temporal requirements for torsinA in normal motor function and gene replacement therapy, we developed a mouse line enabling spatiotemporal control of the endogenous torsinA allele. Suppressing torsinA during embryogenesis caused dystonia-mimicking behavioral and neuropathological phenotypes. Suppressing torsinA during adulthood, however, elicited no discernible abnormalities, establishing an essential requirement for torsinA during a developmental critical period. The developing CNS exhibited a parallel "therapeutic critical period" for torsinA repletion. Although restoring torsinA in juvenile DYT1 mice rescued motor phenotypes, there was no benefit from adult torsinA repletion. These data establish a unique requirement for torsinA in the developing nervous system and demonstrate that the critical period genetic insult provokes permanent pathophysiology mechanistically delinked from torsinA function. These findings imply that to be effective, torsinA-based therapeutic strategies must be employed early in the course of DYT1 dystonia.

Atypical presentations of DYT1 dystonia with acute craniocervical onset.

DYT1 gene mutations lead to early-onset dystonia that begins with focal limb onset and spreads to other body regions within 5 years, with typical sparing of the oromandibular muscles. In the present study, we describe two patients with an unusual presentation of the disease.

Long term follow-up results of deep brain stimulation of the Globus pallidus interna in pediatric patients with DYT1-positive dystonia.

OBJECTIVES: Primary generalized dystonia (PGD) due to heterozygous torsin 1A (TOR1A) gene mutation (DYT1) is a childhood onset dystonia with rapid deterioration of symptoms, leading to severe disability in adolescence. Globus pallidus interna deep brain stimulation (GPi-DBS) has been shown to provide significant improvement in these cases. METHODS: This was a retrospective study of TOR1A mutation positive dystonia patients, conducted at a university hospital from 2006 to 2018. Burke-Fahn-Marsden Dystonia Rating Scale (BFM-DRS) was used to evaluate dystonia severity before and after surgery. Emergence of postsurgical parkinsonian symptoms was evaluated using the Unified Parkinson Disease Rating Scale (UPDRS) part III. Montreal Cognitive Assessment (MOCA) was applied to assess cognitive dysfunction. SPSS version 18 was used for data analysis. RESULTS: Eleven patients entered for analysis with an average age of 22.36 (±3.35) years (range: 18-28). Seven patients (63.6 %) were female. Mean follow-up period was 8.72 (±0.87). Difference between baseline and most recent BFM scores was significant (disability: 10.5 ±4.52 versus 2.09 (±3.20), P: 0.001; severity: 48.45 (±17.88) versus 9.36 (±10.47), P<0.001). The mean MOCA and UPDRS III scores after 7-9 years of DBS were 27.18 (±2.99), and 6.09 (±4.15), respectively. CONCLUSION: Our experience confirms that GPi-DBS in pediatric patients with DYT1 dystonia is overall successful, with significant and long-lasting positive effects on motor and cognitive functions. There was no prominent side effect in long-term follow up.

Disease Stabilization of DYT1-Positive Primary Generalized Dystonia With Deep Brain Stimulation of the Globus Pallidus Interna: A 15-Year Follow-up.

BACKGROUND AND IMPORTANCE: Primary generalized dystonia (PGD) is a genetic form of dystonia that frequently displays pharmacological resistance and progresses quickly after onset. Deep brain stimulation (DBS) has been used successfully to treat refractory dystonia, specifically globus pallidus interna (GPi) DBS for DYT1-positive PGD patients. Long-term follow-up of the safety and efficacy falls short of the longevity seen in other diseases treated with DBS. CASE PRESENTATION: A male patient presented for neurosurgical evaluation with scapular winging, hand contractures, and violent truncal spasms, which forced him to be bedridden. After failing conservative therapy, the 18-yr-old patient was implanted with bilateral GPi-DBS. DBS parameter adjustments were made primarily within the first 3 yr after implantation, with nominal changes thereafter. Initial settings were contact of 3 + 0-, amplitude of 4.9 V, frequency of 185 Hz, and pulse width of 270 µsec on the left and 3 + 0-, 2.8 V, 185 Hz, and 120 µsec on the right. Current settings are 3 + 2 + 1-, 5.2 V, 130 Hz, 330 µsec on the left and 3 + 0-, 3.5 V, 185 Hz, and 180 µsec on the right and have been relatively unchanged in the past 4 yr. Unified dystonia rating scale scores reveal a significant decrease in dystonic symptoms. CONCLUSION: While prior reports have shown that GPi-DBS is effective for dystonia, this is the first with 15 yr of long-term follow-up showing disease stabilization, suggesting that stimulation is efficacious and can potentially prevent disease progression. This report reaffirms previous reports that recommend early surgical intervention before the onset of permanent musculoskeletal deficits.

Neuropsychological and Neuropsychiatric Features of Idiopathic and DYT1 Dystonia and the Impact of Medical and Surgical treatment.

Dystonia is a hyperkinetic movement disorder, characterized by sustained or intermittent muscle contractions causing abnormal, often repetitive, movements, postures, or both. Executive dysfunction is a feature of cognitive function in idiopathic and DYT1 dystonia. Psychiatric morbidity is increased in dystonia, and depression, anxiety, obsessive compulsive disorders are the most common disorders. Sleep problems and pain are also frequently experienced. Evidence suggest that mood and anxiety disorders are intrinsic to the neurobiology of dystonia, but also that psychiatric co-morbidity can be secondary to pain experience and the psychosocial functioning and quality of life of the patients. Medical treatment of dystonia with botulinum toxin injections into affected muscles or with deep brain stimulation surgery improves the symptoms as well as mood and the quality of the patients and does not produce any adverse effects on cognitive function.

The cognitive features of idiopathic and DYT1 dystonia.

Dystonia is a common movement disorder. In this paper, we review the literature on cognitive function in idiopathic and DYT1 dystonia. In idiopathic or DYT1 dystonia, cognition is largely intact with only isolated executive dysfunction. Dystonia patients also have increased temporal and spatial discrimination thresholds, considered endophenotypes of the disorder because deficits are also shown by unaffected relatives and nonmanifesting carriers of the DYT1 mutation. Anticholinergic medication in high doses can be associated with memory impairment in dystonia. The successful treatment of dystonia with botulinum toxin injections or deep brain stimulation does not produce any major adverse effects on cognition. The aspects of cognition that require further investigation in future studies of dystonia include inhibitory control, decision making, and social cognition. © 2017 International Parkinson and Movement Disorder Society.

Brain Stimulation for Torsion Dystonia.

IMPORTANCE: Dystonia is a heterogeneous neurologic disorder characterized by abnormal muscle contractions for which standard medical therapy is often inadequate. For such patients, therapeutic brain stimulation is becoming increasingly used. OBJECTIVES: To review the evidence and effect sizes for treating different types of dystonia with different types of brain stimulation and to discuss recent advances relevant to patient selection, surgical approach, programming, and mechanism of action. EVIDENCE REVIEW: PubMed was searched for publications on the clinical effect of brain stimulation in dystonia up through December 31, 2014. Recent meta-analyses, consensus statements, and evidence-based guidelines were incorporated. Emphasis was placed on deep brain stimulation (DBS) and randomized clinical trials; however, other stimulation modalities and trial designs were included. For each intervention the mean change in dystonia severity, number of patients studied, and evidence of efficacy based on American Academy of Neurology criteria were determined. FINDINGS: Strong (level B) evidence supports the use of DBS for the treatment of primary generalized or segmental dystonia, especially when due to mutation in the DYT1 gene, as well as for patients with cervical dystonia. Large effect sizes have also been reported for DBS treatment of tardive dystonia, writer's cramp, cranial dystonia, myoclonus dystonia, and off-state dystonia associated with Parkinson disease. Lesser benefit is generally seen in dystonia secondary to structural brain damage. Other brain stimulation techniques, including epidural cortical stimulation and noninvasive brain stimulation, have been investigated, but generally report smaller effect sizes in fewer patients. CONCLUSIONS AND RELEVANCE: Patients with dystonia that is not adequately controlled with standard medical therapy should be referred for consideration of DBS, especially patients with generalized, segmental, or cervical dystonia. Other less-invasive stimulation modalities require further research before being considered a therapeutic alternative.

[Cognitive functions in patients with primary torsion dystonia treated with pallidal deep brain stimulation].

Forty-three patients with primary dystonia underwent neuropsychological assessment according to the method of A.R. Luria. Twenty-three patients with generalized dystonia and 20 with local forms (cervical and craniocervical) were included in the study. All patients were evaluated before pallidal deep brain stimulation (DBS GPi), 32 patients were examined 3-6 days after surgery, and 26 patients - during the first two years of the postoperative follow-up. The evaluation before surgery revealed cognitive impairment in 41 patients. The most common were mnemonic impairment, inertness and preservation in different tests, and spatial function decline. Thus, patients with local forms more frequently had troubles with performance memory tests, whereas spatial function disorders were more common in patients with generalized forms. The deterioration of cognitive functions was observed in 28 patients in the early postoperative period. Moreover, the group of patients with local forms had poorer results. The neuropsychological evaluation after 3-6 months of the postoperative follow-up showed the restoration of cognitive functions to the preoperative level. Neuropsychological syndrome observed in patients with dystonia was generally similar to that found in patients with lesions of the frontal lobe, the caudate nucleus, and the cerebellum.

Tolerance of early pallidal stimulation in pediatric generalized dystonia.

The authors report on 2 cases of pediatric generalized dystonia with a DYT1 mutation; the patients, an 11-year-old girl and a 9-year-old boy, underwent chronic, pallidal deep brain stimulation (DBS) of the globus pallidus internus (GPi). The dystonic postures in both cases showed dramatic improvements with pallidal DBS, but each patient's symptoms gradually recurred within a year, irrespective of exhaustive readjustments of the stimulation settings. After the recurrence of the dystonic symptoms, the DBS leads were replaced within the GPi in one patient (Case 1) and additional DBS leads were implanted into the bilateral subthalamic nuclei in the other patient (Case 2). Neither measure produced any further clinical benefit, and the patient in Case 2 died of status dystonicus 2 days after reoperation. These findings suggest that early pallidal DBS for pediatric dystonia is indeed effective, although there are some cases in which its therapeutic effect is lost. One possible reason may be the ability of the preadolescent brain to tolerate chronic electrical stimuli during the active maturation process.

Pallidal stimulation in children: comparison between cerebral palsy and DYT1 dystonia.

The authors compared the outcomes of 17 children aged 7 to 15 years with DYT1 dystonia or cerebral palsy following deep brain stimulation. While patients with cerebral palsy presented with significantly greater motor disability than the DYT1 cohort at baseline, both groups demonstrated improvement at 1 year (cerebral palsy = 24%; DYT1 = 6%). The group as a whole demonstrated significant improvement on the Barry-Albright Dystonia Scale across time. Gains in motor function were apparent in both axial and appendicular distributions involving both upper and lower extremities. Gains achieved by 6 months were sustained in the cerebral palsy group, whereas the DYT1 group demonstrated continued improvement with ongoing pallidal stimulation beyond 18 months. Young patients with dystonia due to cerebral palsy responded comparably to patients with DYT1 dystonia. The severity of motor impairment in patients with cerebral palsy at baseline and follow-up raises the issue of even earlier intervention with neuromodulation in this population to limit long-term motor impairments due to dystonia.

Pallidal deep brain stimulation for DYT6 dystonia.

BACKGROUND: Mutations of the THAP1 gene were recently shown to underlie DYT6 torsion dystonia. Little is known about the response of this dystonia subtype to deep brain stimulation (DBS) at the internal globus pallidus (GPi). METHODS: Retrospective analysis of the medical records of three DYT6 patients who underwent pallidal DBS by one surgical team. The Burke-Fahn-Marsden Dystonia Rating scale served as the primary outcome measure. Comparison is made to 23 patients with DYT1 dystonia also treated with GPi-DBS by the same team. RESULTS: In contrast with the DYT1 patients who exhibited a robust and sustained clinical response to DBS, the DYT6 patients exhibited more modest gains during the first 2 years of therapy, and some symptom regression between years 2 and 3 despite adjustments to the stimulation parameters and repositioning of one stimulating lead. Microelectrode recordings made during the DBS procedures demonstrated no differences in the firing patterns of GPi neurons from DYT1 and DYT6 patients. DISCUSSION: Discovery of the genetic mutations responsible for the DYT6 phenotype allows for screening and analysis of a new homogeneous group of dystonia patients. DYT6 patients appear to respond less robustly to GPi-DBS than their DYT1 counterparts, most likely reflecting differences in the underlying pathophysiology of these distinct genetic disorders. CONCLUSIONS: While early results of pallidal DBS for DYT6 dystonia are encouraging, further research and additional subjects are needed both to optimise stimulation parameters for this population and to elucidate more accurately their response to surgical treatment.

[Acupuncture in emergency medicine : results of a case series]. / Akupunktur in der Notfallmedizin : Ergebnisse einer Fallserie.

BACKGROUND: Acupuncture (AP) might be indicated in emergency medicine. This case series was performed to demonstrate the practicability and possible effects of AP in emergency medical services (EMS) as a basis for randomized controlled trials (RCT). SUBJECTS AND METHODS: A total of 60 patients (average age 55.4±23.0 years, 57% female) treated by the EMS received AP if applicable. Main outcome parameter was to rate the symptom alleviating effect of acupuncture treatment on a 4-point scale or by VAS. RESULTS: Of the 60 patients 35 (58%) reported considerable improvement, 15 patients (25%) reported complete relief and 10 patients (17%) reported no changes in the cardinal symptom. The predominant symptoms alleviated by AP were nausea (n=31) and vomiting (n=21). Pericardium 3 and 6 (27%) and Spleen 6 and 9 were the most commonly used AP points. CONCLUSION: This case series demonstrates that AP can alleviate certain symptoms in emergency patients. The results of the study provide data as a basis to perform clinical controlled trials on the effectiveness of AP in emergency medicine.

Management of DYT1 dystonia throughout pregnancy.

A 30-year-old woman with generalised DYT1 dystonia, controlled with medication, presented at 9 weeks gestation with an unplanned pregnancy. A number of learning points were highlighted in management of the patient's dystonia alongside pregnancy including avoidance of excessive medication exposure to the fetus, while maintaining symptom control to a level acceptable and safe for the patient and prenatal diagnostic testing. In our case there was no overt ill effect to the newborn. This is a common worry among pregnant women with dystonia and as such the authors felt it important to report.

DYT6 dystonia: mutation screening, phenotype, and response to deep brain stimulation.

Mutations in THAP1, a gene encoding a nuclear pro-apoptotic protein, have been associated with DYT6 dystonia. First reports on the phenotype of DYT6 dystonia show an early onset dystonia with predominant cranio-cervical and laryngeal involvement. Here we assessed the frequency and phenotype of THAP1 mutation carriers in a large Dutch cohort of adult-onset (≥26 years) dystonia (n = 388) and early-onset dystonia (n = 67) patients. We describe the phenotype of DYT6 dystonia patients and their response on GPi DBS. Overall, 3 nonsynonymous heterozygous mutations were detected in the early-onset group (4.5%). Two DYT6 families were identified, showing a heterozygous phenotype. All patients had segmental or generalized dystonia, often associated with profound oromandibular and laryngeal involvement. No nonsynonymous mutations were found in patients with adult-onset focal dystonia. Rare synonymous variants were identified in conserved regions of THAP1, two in the adult-onset cervical dystonia group and one in the control group. Four DYT6 dystonia patients were treated with GPi DBS with moderate to good response on motor function but marginal benefit on speech.

Stimulation of the globus pallidus internus in a patient with DYT1-positive primary generalized dystonia: a 10-year follow-up.

The authors report the case of DYT1-positive primary generalized dystonia refractory to medical management that was successfully treated with continuous deep brain stimulation of the internal segment of the globus pallidus. Prior studies have shown that neuromusculoskeletal deficits can remain permanent if early surgical intervention is not undertaken. The authors report prolonged efficacy and safety over a 10-year period in a 28-year-old man.

Restoration of erect posture by deep brain stimulation of the globus pallidus in disabling dystonic spinal hyperextension.

Dystonia is a movement disorder notoriously difficult to treat. While primary dystonia is classically considered to respond well to deep brain stimulation (DBS), treatment of secondary dystonia yields variable results. Patient selection should be done on a case-by-case basis. Clearly, there is a need to accumulate additional information with regard to prognostic factors that may aid neurosurgeons in selecting those patients in whom the disorder is most likely to respond favorably to pallidal DBS. The authors report the case of a 29-year-old man with secondary dystonia due to perinatal hypoxia. The most prominent symptom was what we have termed ectatocormia-that is, severe, fixed truncal hyperextension and retrocollis, exacerbated by phasic, twisting movements of the trunk and head. This made it impossible for the patient to maintain a normal upright posture or to walk. The patient underwent bilateral DBS of the globus pallidus internus (GPi), and the authors observed impressive improvement in motor abilities and function. The patient's body adopted the normal upright posture and he became able to walk again, 4 months after the commencement of GPi stimulation. This report, along with others, emphasizes that the GPi as an ideal target for alleviating axial tonic symptoms. The presence of normal MR imaging findings, a phenotypical purity of predominantly dystonic symptoms, and a younger age seem to favor a positive outcome.

A family with a hereditary form of torsion dystonia from northern Sweden treated with bilateral pallidal deep brain stimulation.

To evaluate pallidal DBS in a non-DYT1 form of hereditary dystonia. We present the results of pallidal DBS in a family with non-DYT1 dystonia where DYT5 to 17 was excluded. The dystonia is following an autosomal dominant pattern. Ten members had definite dystonia and five had dystonia with minor symptoms. Four patients received bilateral pallidal DBS. Mean age was 47 years. The patients were evaluated before surgery, and "on" stimulation after a mean of 2.5 years (range 1-3) using the Burke-Fahn-Marsden scale (BFM). Mean BFM score decreased by 79 % on stimulation, from 42.5 +/- 24 to 9 +/- 6.5 at the last evaluation. Cervical involvement improved by 89%. The 2 patients with oromandibular dystonia and blepharospasm demonstrated a reduction of 95% regarding these symptoms. The present study confirms the effectiveness of pallidal DBS in a new family with hereditary primary segmental and generalized dystonia.

Genetics and treatment of dystonia.

The torsion dystonias encompass a broad collection of etiologic subtypes, often divided into primary and secondary classes. Tremendous advances have been made in uncovering the genetic basis of dystonia, including discovery of a gene causing early onset primary torsion dystonia-a GAG deletion in exon 5 of the DYT1 gene that encodes torsinA. Although the exact function of torsinA remains elusive, evidence suggests aberrant localization and interaction of mutated protein; this may result in an abnormal response to stress or interference with cytoskeletal events and the development of neuronal brain pathways. Breakthroughs include the discovery of a genetic modifier that protects against clinical expression in DYT1 dystonia and the identification of the gene causing DYT6, THAP1. The authors review genetic etiologies and discuss phenotypes as well as counseling of patients regarding prognosis and progression of the disease. They also address pharmacologic and surgical treatment options for various forms of dystonia.

Deep brain stimulation for primary generalized dystonia: long-term outcomes.

BACKGROUND: Pallidal deep brain stimulation (DBS) is the best therapeutic option for patients with disabling primary generalized dystonia (PGD) that is refractory to medications. However, little is known about its long-term effects. OBJECTIVE: To describe long-term clinical outcomes in patients with PGD who underwent pallidal DBS. DESIGN: Case series. SETTING: University hospital. PATIENTS: Thirty consecutive patients with at least 2 years' follow-up after pallidal DBS for intractable PGD. INTERVENTIONS: Pallidal DBS and annual follow-up examinations up to 8 years after DBS implantation. MAIN OUTCOME MEASURES: Clinical outcome as measured by changes in the Burke-Fahn-Marsden dystonia scale, incidence and prevalence of adverse events, total electrical energy delivered, and implantable pulse generator longevity. RESULTS: Twenty-three patients were followed for 3 years, 13 for 4 years, 9 for 5 years, 5 for 6 years, 5 for 7 years, and 1 for 8 years after DBS. Overall improvement at 1 year was maintained in all at successive yearly examinations. There were no intraoperative complications; hardware-related adverse events were infrequent. Rare stimulation-related adverse events primarily affected speech. Implantable pulse generators were replaced every 24 months on average in patients who received initial stimulation at 130-Hz frequency. No battery was replaced, for up to 48 months, in 20 patients initially stimulated using 60 Hz. Clinical outcome did not depend on high energies of stimulation. CONCLUSIONS: Pallidal DBS is a safe and effective treatment for PGD, with improvement sustained for up to 8 years in 1 patient. Low energies of stimulation, although they did not affect clinical outcome, were associated with longer battery life.