Neural tube defects in the Cape Town area, 1975-1980

During the period 1975-1980, 105 infants out of a total of 116 859 delivered at selected hospitals in the Cape Town area had a neural tube defect. The combined incidence of spina bifida and anencephaly in Whites was approximately 1/300 births, which is similar to that generally encountered in the UK. However, the incidence in other ethnic groups was appreciably lower at 1/1250 and 1/2000 births for the Coloured (mixed ancestry) and Black groups respectively.     

HLA DQ beta restriction fragment length polymorphism and rheumatoid arthritis. Association between DQw7 and rheumatoid arthritis in DR4-positive subjects.

Two variants of the HLA-DR4-linked DQw3 allele, namely DQw7 and DQw8, were analysed in patients of mixed ancestry (Cape Coloureds) with rheumatoid arthritis and in healthy individuals from the same population group using a DQ beta-specific cDNA probe. The DQw7 allele, identified by 3,4 kb Hind III or 3,7 kb and 6,9 kb Bam HI DQ beta-specific restriction fragments, was expressed in 93% of DR4-positive patients (N = 15), compared with 12.5% DR4-positive normal individuals (N = 8). This DQ variant showed a highly significant association (relative risk = 98; P less than 0.0001) with rheumatoid arthritis in this population group and may play a role in their susceptibility to this disease.     

Primary dystonia is more responsive than secondary dystonia to pallidal interventions: outcome after pallidotomy or pallidal deep brain stimulation

OBJECTIVE: The response of patients with dystonia to pallidal procedures is not well understood. In this study, we assessed the postoperative outcome of patients with primary and secondary dystonia undergoing pallidotomy or pallidal deep brain stimulation. METHODS: Fifteen patients with dystonia had pallidal surgery (lesions or deep brain stimulation). These included nine patients with primary dystonia (generalized and cervical dystonias) and six with secondary dystonia (generalized, segmental, and hemidystonias). There were nine male patients and six female patients. The mean age at onset was 21 years for primary dystonia and 18 years for secondary dystonia. The primary outcome measure was a Global Outcome Scale score for dystonia at 6 months after surgery. Other outcome measures were the Burke-Fahn-Marsden Dystonia Rating Scale and Toronto Western Spasmodic Torticollis Rating Scale scores. RESULTS: The mean Global Outcome Scale score at 6 months for patients with primary dystonia was 3 (improvement in both movement disorder and function). In contrast, patients with secondary dystonia had a mean score of 0.83 (mild or no improvement in movement disorder with no functional improvement). All patients with primary dystonia had normal brains by magnetic resonance imaging, whereas five of six patients with secondary dystonia had basal ganglia abnormalities on their magnetic resonance imaging scans. CONCLUSION: This study indicates that primary dystonia responds much better than secondary dystonia to pallidal procedures. We could not distinguish a difference in efficacy between pallidotomy and pallidal deep brain stimulation. The presence of basal ganglia abnormalities on the preoperative magnetic resonance imaging scan is an indicator of a lesser response to pallidal interventions for dystonia.     

Comparisons of body size, composition, and whole body bone mass between North American and South African children.

We compared whole body BMC of 811 black, white, and mixed ancestral origin children from Detroit, MI; Johannesburg, South Africa; and Cape Town, South Africa. Our findings support the role of genetic and environmental influences in the determination of bone mass in prepubertal children. INTRODUCTION: Higher bone mass and lower fracture rates have been shown in black compared with white children and adults in North America. MATERIALS AND METHODS: We compared whole body BMC (WBBMC), whole body fat mass (WBFM), and whole body fat free soft tissue (WBFFST) data between three ethnic groups of children from Detroit, MI (n = 181 white, USW; n = 230 black, USB), Johannesburg, South Africa (n = 73 white, SAW; n = 263 black, SAB), and Cape Town, South Africa (n = 64 mixed ancestral origin, SAM). RESULTS: SAB and SAW groups were slightly older than USW and USB groups (9.5 +/- 0.3 versus 9.3 +/- 0.1 yr); however, USB and USW boys were significantly taller, were heavier, and had a higher BMI than SAM and SAB boys. USB girls were significantly taller than SAB girls and heavier than SAB and SAM girls. In South Africa and the United States, black children had a significantly higher WBBMC than white children, after adjusting for selected best predictors. After adjusting for age, weight, and height, WBBMC was significantly higher in the SAB and SAW boys than in USW and USB and in the SAM group compared with the USW and USB groups. WBFFST and WBFM made significant contributions to a best linear model for log(WBBMC), together with age, height, and ethnicity. The best model accounted for 79% of the WBBMC variance. When included separately in the model, the model containing WBFFST accounted for 76%, and the model containing WBFM accounted for 70%, of the variance in WBBMC. CONCLUSIONS: WBBMC is lower in children of European ancestry compared with African ancestry, irrespective of geographical location; however, South African children have significantly higher WBBMC compared with USB and USW groups, thereby acknowledging the possible contribution of environmental factors. Reasons for the significantly higher WBBMC in the children of mixed ancestral origin compared with the other groups need to be studied further.     

Treatment of dystonic syndromes by chronic electrical stimulation of the internal globus pallidus

AIM: Dystonia is a medically intractable condition causing twisting or myoclonic movements and abnormal postures. There is an important heterogeneity among etiologies of dystonia. The electrical stimulation of the globus pallidus has been used successfully in primary generalized dystonia. The aim of this study was to examine the long-term efficacy and safety of deep brain stimulation (DBS) in the treatment of primary and secondary generalized dystonia in children and adults. METHODS: Fifty-three patients were included. Electrodes were bilaterally implanted under stereotactic guidance and connected to neurostimulators, subcutaneously inserted. Efficacy was evaluated by comparing scores on the clinical and functional Burke-Marsden-Fahn dystonia rating scales (BMFDRS) before and after implantation. Patients were divided into 3 groups: group 1 comprised 15 patients with DYT1 dystonia; group 2, 17 patients with dystonia of unknown etiology and group 3, 21 patients with secondary dystonia. The mean follow-up was 26.6+/-12.3 months for primary dystonia and 23.1+/-11.8 for secondary dystonia. RESULTS: After 1 year, the improvement of the clinical score is 71% in group 1, 74% in group 2 and 31% in group 3. The functional score was improved by 63% in group 1, 49% in group 2 and 7% in group 3. We did not find any significant difference between children and adults. In secondary dystonia, efficacy of the stimulation is more limited. The efficacy of the stimulation improved with time for the 3 groups. COMCLUSION: Electrical stimulation of the internal globus pallidus proved to be an effective treatment for generalized dystonia and should be considered as first-line therapy.     

Pallidal deep brain stimulation for longstanding severe generalized dystonia in Hallervorden-Spatz syndrome. Case report

Generalized dystonia is one of the most disabling movement disorders. Ablative stereotactic surgery such as pallidotomy has been performed for medically refractory dystonia. Recently, deep brain stimulation (DBS) has appeared as an alternative to ablative procedures. Nevertheless, there have been few published reports detailing improvement in dystonia with DBS. This 36-year-old man with Hallervorden-Spatz syndrome suffered from intractable primary generalized dystonia for 28 years. He was completely dependent for activities of daily living and wheelchair bound because of continuous severe dystonic movements in the face, tongue, neck, trunk, and upper and lower extremities while at rest. The Burke-Fahn-Marsden (BFM) Dystonia Rating Scale score was 112 (maximum 120 points). Bilateral DBS of the globus pallidus internus was performed and resulted in marked improvement in motor functioning and dystonic symptoms with a significant reduction in disability. The BFM score improved to 22.5 points (80% improvement) at 3 months postsurgery and the patient's dystonia was still well suppressed 1 year after surgery. Bilateral pallidal stimulation is an effective and safe treatment for intractable generalized dystonia in Hallervorden-Spatz syndrome, even if the disability is severe and longstanding.     

A survey of Italian cases of dystonia treated by deep brain stimulation

AIM: The aim of this study was to report on Italian cases of dystonia treated by deep brain stimulation up to the end of 2005. METHODS: Retrospective survey. Presentation of data collection among all Italian neurosurgical institutions. RESULTS: Seven out of 123 Italian neurosurgical centres were enrolled. Sixty-nine patients were operated. According to different classification criteria, cases were grouped as follows: 37 primary and 32 secondary dystonia; 61 generalized and 8 focal dystonia; 16 patients aged at onset <2 years, 22 aged 3-12 years, 14 aged 13-20 years, 17 aged >20 years. Primary dystonia (DYT) mutation 1 was identified in 21% of primary generalized dystonia. Age at surgery was <15 years in 21.7% of cases (N.=15). Mean time between clinical onset and surgery was 17 years. Globus pallidus internus (GPi) was chosen for implantation in all cases. Type of anesthesia, method of target localization, lead and implanted pulse generator (IPG) model differed among centres. Surgical complications occurred in 19% of patients, but at a higher rate (33%) in the pediatric subgroup. Stimulation parameters varied among centres, but the main scheme was 90-120 micros and 130 Hz. Follow-up duration ranged from 3 to 84 months (longer than 24 months in 50% of patients). Mean Burke-Fahn-Marsden scale (BFM) improvement was 42% for both severity and disability score, ranging from 0% to 92%. Improvement of at least 50% in BFM severity score has been reached by 45% of primary and 37% of secondary dystonia. Clinical results were better in the DYT1 subgroup, with 60% of cases improving more than 50%. Among secondary dystonia, the drug-induced group had very good results too. On the contrary delayed surgery and presence of comorbidity were negatively correlated to the outcome. CONCLUSION: In this series, primary generalized dystonia has a better outcome, especially if associated to DYT1 mutation. Among secondary dystonia, the drug-induced group has very good RESULTS: Correlation analysis of time to surgery and associated comorbidity suggests that earlier surgery is advisable.     

Benefit of bilateral pallidotomy in the treatment of generalized dystonia. Case report

This 29-year-old man with cerebral palsy complicated by generalized dystonia was treated by simultaneous bilateral posteroventral pallidotomy. Postoperatively, there was slow, but steady, improvement in the patient's dystonia and disability. However, the improvement in abnormal movements was only prominent for cervical dystonia and oromandibular dyskinesia. The patient's Burke-Fahn-Marsden dystonia scores were 51 preoperatively and 37, 33.5 and 33.5, at 3, 6, and 12 months postoperatively, respectively, demonstrating a maximum improvement of 34%. These results suggest that pallidotomy can be an alternative therapy for those patients suffering from intractable generalized dystonia.     

Comparison of thalamotomy and pallidotomy for the treatment of dystonia

OBJECTIVE: Thalamotomy and, more recently, pallidotomy have been used to treat selected patients with intractable dystonia, although few studies have compared the effectiveness of these two surgical procedures. In this study, we compare our results using thalamotomy and pallidotomy to treat patients with different forms of dystonia, and we discuss our results in the context of other published series. METHODS: Thirty-two patients with intractable dystonia underwent thalamotomy (n = 18) or pallidotomy (n = 14). Dystonia was classified according to cause and distribution, and each patient was evaluated postoperatively at two or more time points, using a global outcome scale. RESULTS: Although comparisons are limited by differences between the two surgical groups, including longer follow-up periods for the thalamotomy group, differences in symptom distribution, and more bilateral procedures for the pallidotomy group, patients with primary dystonia who underwent pallidotomies demonstrated significantly better long-term outcomes than did patients who underwent thalamotomies (P = 0.0467). Patients with secondary dystonia experienced more modest improvements after either procedure, with little or no difference in outcomes between the two procedures. CONCLUSION: For patients with primary dystonia, pallidotomy seems to result in better outcomes than does thalamotomy.     

Stimulation-induced parkinsonism after posteroventral deep brain stimulation of the globus pallidus internus for craniocervical dystonia

The authors report on a patient with craniocervical dystonia who was treated with bilateral GPi stimulation, with excellent improvement in dystonia but at the cost of stimulation-induced, reversible parkinsonism. Stimulation through ventral contacts resulted in maximal relief of craniocervical dystonia but induced considerable hypophonia, bradykinesia, rigidity, freezing, and impaired postural reflexes. Stimulation through dorsal contacts alleviated parkinsonism, but resulted in the return of dystonia. No stimulation parameters could alleviate the dystonia without inducing parkinsonism over the course of his 4-year follow-up.     

Chronic stimulation of the globus pallidus internus for treatment of non-dYT1 generalized dystonia and choreoathetosis: 2-year follow up

OBJECT: The authors studied the long-term efficacy of deep brain stimulation (DBS) of the posteroventral lateral globus pallidus internus up to 2 years postoperatively in patients with primary non-DYT1 generalized dystonia or choreoathetosis. The results are briefly compared with those reported for DBS in DYT1 dystonia (Oppenheim dystonia), which is caused by the DYT1 gene. METHODS: Enrollment in this prospective expanded pilot study was limited to adult patients with severely disabling, medically refractory non-DYT1 generalized dystonia or choreoathetosis. Six consecutive patients underwent follow-up examinations at defined intervals of 3 months, 1 year, and 2 years postsurgery. There were five women and one man, and their mean age at surgery was 45.5 years. Formal assessments included both the Burke-Fahn-Marsden dystonia scale and the recently developed Unified Dystonia Rating Scale. Two patients had primary generalized non-DYT1 dystonia, and four suffered from choreoathetosis secondary to infantile cerebral palsy. Bilateral quadripolar DBS electrodes were implanted in all instances, except in one patient with markedly asymmetrical symptoms. There were no adverse events related to surgery. The Burke-Fahn-Marsden scores in the two patients with generalized dystonia improved by 78 and 71% at 3 months, by 82 and 69% at 1 year, and by 78 and 70% at 2 years postoperatively. This was paralleled by marked amelioration of disability scores. The mean improvement in Burke-Fahn-Marsden scores in patients with choreoathetosis was 12% at 3 months, 29% at 1 year, and 23% at 2 years postoperatively, which was not significant. Two of these patients thought that they had achieved marked improvement at 2 years postoperatively, although results of objective evaluations were less impressive. In these two patients there was a minor but stable improvement in disability scores. All patients had an improvement in pain scores at the 2-year follow-up review. Medication was tapered off in both patients with generalized dystonia and reduced in two of the patients with choreoathetosis. All stimulation-induced side effects were reversible on adjustment of the DBS settings. Energy consumption of the batteries was considerably higher than in patients with Parkinson disease. CONCLUSIONS: Chronic pallidal DBS is a safe and effective procedure in generalized non-DYT1 dystonia, and it may become the procedure of choice in patients with medically refractory dystonia. Postoperative improvement of choreoathetosis is more modest and varied, and subjective ratings of outcome may exceed objective evaluations.     

No evidence for a large difference in ALS frequency in populations of African and European origin: a population based study in inner city London

Abstract Previous studies have suggested a lower incidence of ALS in people of African origin. We used a population based register in an urban setting from inner city London postcodes where there is a large population of people of African ancestry to compare the frequency of ALS in people of European and African origin. Population statistics stratified by age, gender and ethnicity were obtained from the 2001 census. Incidence and prevalence were calculated in each ethnic group. Results showed that in a population of 683,194, of which 22% were of African ancestry, 88 individuals with ALS were identified over a seven-year period, including 14 people with African ancestry. The adjusted incidence in people of African ancestry was 1.35 per 100,000 person-years (95% CI 0.72-2.3) and in those of European ancestry 1.97 per 100,000 person-years (95% CI 1.55-2.48). In conclusion, in this small population based study we could not detect a difference in rates of ALS between people of African ancestry and those of European ancestry.     

Health status of hostel dwellers. Part IV. Immunisation of children

The immunisation status of children (0-5 years) living in the Zones, an urban migrant council-built hostel in Langa, was investigated to examine the effect of migrant labour and related to this, the effect of circular or oscillating migration between Cape Town and the eastern Cape (Transkei/Ciskei) on access to this preventive health care measure. 'Road-to-Health' cards were available for 69.4% of subjects--78.8% for those born in Cape Town and 50.8% for those born in Transkei. Immunisation of 'Road-to-Health' card holders ranged from 71.8% to 95%. The range dropped to 41-79.1% if it was assumed that children without 'Road-to-Health' cards (i.e. without positive proof of immunisation) had not been immunised. Children born in Cape Town have a significantly higher immunisation coverage than children born elsewhere (Transkei accounted for 82.7% of these children). Immunisations administered in Cape Town numbered 80.6%, while 62.6% of subjects were born in Cape Town. In Transkei, payment is required for immunisation, in Cape Town it is free. By implication, cost appeared to be an important reason for low coverage in Transkei. The findings of this study suggested that hostel migrant children who had access to the Cape Town health services through working parents had better immunisation coverage than children at the home-base who seldom or never reached the city.     

Deep brain stimulation for dystonia

Opinion statement Dystonia refers to movement disorders characterized by sustained muscle contractions that produce abnormal postures, twisting movements, and other abnormal involuntary movements. A spectrum of etiologies underlies the various dystonia syndromes, ranging from genetic conditions to brain injury. First-line therapy for dystonia consists of pharmacologic agents of several classes and, particularly for focal dystonia, chemodenervation therapy with botulinum toxin. Many patients with dystonia realize an inadequate response to those treatments, and for such patients whose symptoms are sufficiently troublesome, surgical treatment can be used to reduce symptoms and improve function. Previously, the ablative procedures of thalamotomy and pallidotomy were used, in which a permanent destructive lesion was made in the motor territory of the thalamus or the globus pallidus. More recently, the device-based therapy of deep brain stimulation (DBS) has emerged as the preferred surgical treatment for dystonia and other movement disorders for most patients who require operative intervention. DBS uses a surgically implanted brain lead connected to an implanted neurostimulator to deliver chronic, high-frequency electrical stimulation to one of several deep nuclei. For dystonia, stimulation directed at the globus pallidus internus has been the most thoroughly studied to date. Advantages of DBS include its relatively non-destructive nature, its adjustability and reversibility, and its capacity to be used bilaterally in a safe manner. Use of DBS to treat dystonia is a rapidly evolving area, and preliminary evidence suggests that primary dystonia linked to genetic mutation, other primary dystonias, and tardive dystonic syndromes respond most dramatically to treatment with DBS, whereas secondary dystonia tends to be less responsive.     

Deep brain stimulation for dystonia in adults. Overview and developments

The renaissance of functional neurosurgery in the treatment of Parkinson's disease has sparked also the interest in other movement disorders which are refractory to medical treatment. Deep brain stimulation (DBS) has been used only since a few years in dystonia patients. This review summarizes the available data on pallidal and thalamic DBS for various dystonic syndromes. The major advantage of DBS as compared to radiofrequency lesioning is that it allows performing contemporaneous bilateral surgery with relatively low morbidity in these patients. The posteroventral lateral globus pallidus internus (GPi) has been the preferred target in most instances, thus far. While phasic dystonic movements may improve early after surgery, the response of tonic dystonic movements to chronic stimulation may be delayed. The most beneficial results have been achieved in patients with primary genetic generalized and segmental dystonia, myoclonic dystonia, and complex cervical dystonia. Outcome has been varied in patients with other dystonic disorders, in particular those with secondary dystonia. Most studies have reported on relatively short follow-up periods, on single cases, or were retrospective. Pallidal DBS has been shown to be effective in complex cervical dystonia yielding both symptomatic and functional benefit for up to 2.5 years of follow-up. Dramatic improvement has been obtained in children and in adults with DYT1 positive dystonia. Also, patients with non DYT1 genetic dystonia achieved sustained benefit for up to 2 years of follow-up. Preliminary experience indicates that choreoathetosis in patients with cerebral palsy responds less well to pallidal DBS, and that it may not be effective at all in some patients. In single instances unilateral pallidal DBS has been shown to yield valuable benefit in patients with hemidystonia. The experience with DBS for treatment of Meige syndrome and other focal dystonias has been explored only recently. There is much less experience with thalamic DBS for dystonia. Thalamic DBS has been shown to be effective in single cases with posttraumatic dystonia, postanoxic dystonia and paroxysmal nonkinesigenic dystonia. Future perspectives of DBS for treatment of dystonia include the development of new technology, the evaluation of the possible role of other targets, and carefully planned studies to further establish the role of surgery.     

Management of a hemidystonic patient with thalamotomy, campotomy and cervical dorsal root entry zone operation

Several medical and surgical procedures have been presented for treatment of dystonia. Thalamotomy, pallidotomy, and campotomy are some of the surgical choices. This study presents a patient with dystonia who underwent a cervical dorsal root entry zone (DREZ) operation after thalamotomy and campotomy. A 23-year-old man who was resistant to medical treatment presented with left hemidystonia. Thalamotomy and campotomy were performed. The patient remarkably benefited from the procedure but dystonic complaints in his left arm continued. A cervical DREZ operation was performed 5 years after the first operation and the dystonic complaints decreased after the surgery. This article presents a new aspect for the treatment of dystonia. Based on the outcomes of the treatment, DREZ operation may be suggested as an alternative surgical treatment for patients with segmental dystonia located in the extremities.     

Alcohol consumption among South African blacks and its relationship to iron overload

The drinking habits of 123 black men (28 from Cape Town and 95 from Pietermaritzburg) were recorded, and their weekly alcoholic iron intakes calculated. Serum ferritin levels and liver function were measured in 57 subjects (Cape Town 12, Pietermaritzburg 45). Sorghum beer, with its high iron content, was considerably more popular in Pietermaritzburg than Cape Town, and the weekly iron consumption in Pietermaritzburg was significantly higher (P less than 0.05) than in Cape Town. The serum ferritin level was significantly higher in Cape Town than in Pietermaritzburg (P less than 0.05), no significant correlation being found between iron intake and serum ferritin. Age was positively correlated with serum ferritin (P less than 0.01). Of the subjects studied, 74% had abnormal lactate dehydrogenase levels. These results are considered in the light of the numerous problems associated with this type of project. The need for prospective studies in order to demonstrate a causal relationship between alcoholic iron intake and iron overload is emphasized.     

Accuracy of stimulating electrode placement in paediatric pallidal deep brain stimulation for primary and secondary dystonia

Background

Accuracy of electrode placement is an important determinant of outcome following deep brain stimulation (DBS) surgery. Data on accuracy of electrode placement into the globus pallidum interna (GPi) in paediatric patients is limited, particularly those with non-primary dystonia who often have smaller GPi. Pallidal DBS is known to be more effective in the treatment of primary dystonia compared with secondary dystonia.

Objectives

We aimed to determine if accuracy of pallidal electrode placement differed between primary, secondary and NBIA (neuronal degeneration and brain iron accumulation) associated dystonia and how this related to motor outcome following surgery.

Methods

A retrospective review of a consecutive cohort of children and young people undergoing DBS surgery in a single centre. Fused in frame preoperative planning magnetic resonance imaging (MRI) and postoperative computed tomography (CT) brain scans were used to determine the accuracy of placement of DBS electrode tip in Leskell stereotactic system compared with the planned target. The differences along X, Y, and Z coordinates were calculated, as was the Euclidean distance of electrode tip from the target. The relationship between proximity to target and change in Burke-Fahn-Marsden Dystonia Rating Scale at 1 year was also measured.

Results

Data were collected from 88 electrodes placed in 42 patients (14 primary dystonia, 18 secondary dystonia and 10 NBIA associated dystonia). Median differences between planned target and actual position were: left-side X-axis 1.05 mm, Y-axis 0.85 mm, Z-axis 0.94 mm and Euclidean difference 2.04 mm; right-side X-axis 1.28 mm, Y-axis 0.70 mm, Z-axis 0.70 mm and Euclidean difference 2.45 mm. Accuracy did not differ between left and right-sided electrodes. No difference in accuracy was seen between primary, secondary or NBIA associated dystonia. Dystonia reduction at 1 year post surgery did not appear to relate to proximity of implanted electrode to surgical target across the cohort.

Conclusions

Accuracy of surgical placement did not differ between primary, secondary or NBIA associated dystonia. Decreased efficacy of pallidal DBS in secondary and NBIA associated dystonia is unlikely to be related to difficulties in achieving the planned electrode placement.     

A historical review of XDR tuberculosis in the Western Cape province of South Africa

There are limited data on the temporal relationship between the regional introduction of multidrug-resistant tuberculosis (MDR-TB) treatment and the subsequent development of extensively drug-resistant TB (XDR-TB). The first XDR-TB case in the Western Cape province of South Africa was recorded in 1992, approximately 5 - 7 years after the regional introduction of MDR-TB-like treatment. Between 1990 and 2002 we identified 48 patients with XDR-TB in the Cape Metropole region of the Western Cape province. Patients were predominantly HIV-uninfected and median survival was 10.8 months. XDR-TB has therefore been present in the Western Cape at least since 1992. These data inform public health policy relevant to the introduction of new anti-TB drug regimens.     

Myoclonic dystonia: effective treatment by cervical cord stimulation. A case report

A patient is described with myoclonic dystonia, a disorder characterized by a combination of dystonia and myoclonic contractions. A very good response to epidural cervical cord electrical stimulation was obtained. The findings in this case indicate that epidural cervical cord electrical stimulation could be a useful therapeutic approach in cases of myoclonic dystonia.