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Jens Volkmann, Alexander Wolters,
Andreas Kupsch,
Jörg Müller,
Andrea A Kühn,
Gerd-Helge Schneider,
Werner Poewe,
Sascha Hering,
Wilhelm Eisner,
Jan-Uwe Müller, [......],
Geir Ketil Roeste,
Martin Krause,
Volker Tronnier,
Alfons Schnitzler,
Jürgen Voges,
Guido Nikkhah,
Jan Vesper,
Joseph Classen,
Markus Naumann,
Reiner Benecke
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Jens Volkmann, Alexander Wolters,
Andreas Kupsch,
Jörg Müller,
Andrea A Kühn,
Gerd-Helge Schneider,
Werner Poewe,
Sascha Hering,
Wilhelm Eisner,
Jan-Uwe Müller, [......],
Geir Ketil Roeste,
Martin Krause,
Volker Tronnier,
Alfons Schnitzler,
Jürgen Voges,
Guido Nikkhah,
Jan Vesper,
Joseph Classen,
Markus Naumann,
Reiner Benecke
[show abstract]
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ABSTRACT: BACKGROUND: Severe forms of primary dystonia are difficult to manage medically. We assessed the safety and efficacy of pallidal neurostimulation in patients with primary generalised or segmental dystonia prospectively followed up for 5 years in a controlled multicentre trial. METHODS: In the parent trial, 40 patients were randomly assigned to either sham neurostimulation or neurostimulation of the internal globus pallidus for a period of 3 months and thereafter all patients completed 6 months of active neurostimulation. 38 patients agreed to be followed up annually after the activation of neurostimulation, including assessments of dystonia severity, pain, disability, and quality of life. The primary endpoint of the 5-year follow-up study extension was the change in dystonia severity at 3 years and 5 years as assessed by open-label ratings of the Burke-Fahn-Marsden dystonia rating scale (BFMDRS) motor score compared with the preoperative baseline and the 6-month visit. The primary endpoint was analysed on an intention-to-treat basis. The original trial is registered with ClinicalTrials.gov (NCT00142259). FINDINGS: An intention-to-treat analysis including all patients from the parent trial showed significant improvements in dystonia severity at 3 years and 5 years compared with baseline, which corresponded to -20·8 points (SD 17·1; -47·9%; n=40) at 6 months; -26·5 points (19·7; -61·1%; n=31) at 3 years; and -25·1 points (21·3; -57·8%; n=32). The improvement from 6 months to 3 years (-5·7 points [SD 8·4]; -34%) was significant and sustained at the 5-year follow-up (-4·3 [10·4]). 49 new adverse events occurred between 6 months and 5 years. Dysarthria and transient worsening of dystonia were the most common non-serious adverse events. 21 adverse events were rated serious and were almost exclusively device related. One patient attempted suicide shortly after the 6-month visit during a depressive episode. All serious adverse events resolved without permanent sequelae. INTERPRETATION: 3 years and 5 years after surgery, pallidal neurostimulation continues to be an effective and relatively safe treatment option for patients with severe idiopathic dystonia. This long-term observation provides further evidence in favour of pallidal neurostimulation as a first-line treatment for patients with medically intractable, segmental, or generalised dystonia. FUNDING: Medtronic.
The Lancet Neurology 10/2012; · 23.46 Impact Factor
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MMW Fortschritte der Medizin 04/2012; 154(7):59-62.
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Knut Busse,
Robert Heilmann,
Sabine Kleinschmidt,
Mazen Abu-Mugheisib,
Jacqueline Höppner,
Christian Wunderlich,
Irene Gemende,
Lara Kaulitz, Alexander Wolters,
Reiner Benecke,
Uwe Walter
[show abstract]
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ABSTRACT: Characteristic features of Parkinson's disease (PD) are asymmetric parkinsonian motor signs, hyposmia and substantia nigra (SN) hyperechogenicity on transcranial ultrasound. However, each of these features has limited diagnostic value as they may be present, albeit less frequently, in other parkinsonian disorders. Here, the diagnostic sensitivity and specificity of combined assessment of these three features are evaluated.
632 patients with parkinsonism (PD, vascular parkinsonism, atypical parkinsonian syndromes, essential tremor and major depressive disorder with motor slowing) were assessed on the Unified Parkinson's disease Rating Scale for motor asymmetry (right-left score difference ≥2), the 12 item Sniffin' Sticks test (SS-12) and transcranial ultrasound. The derivation (validation) cohort consisted of 517 (115) subjects (193 (35) women; age 65.4±9.6 (62.3±10.3) years) of whom 385 (68) had PD and 132 (47) non-PD parkinsonism; another 21 (6) subjects were not included due to missing transcranial insonability. Of the validation cohort, all patients had a disease duration ≤2 years and observers were blind to diagnoses.
The optimum cut-off values for discrimination of PD were SS-12 score <8 (hyposmia) and SN echogenic size ≥0.24 cm(2) (SN hyperechogenicity). Sensitivity, specificity and positive predictive values for the diagnosis of PD were as follows, for the derivation cohort: motor asymmetry 88%, 54% and 85%; hyposmia 75%, 70% and 88%; SN hyperechogenicity 90%, 63% and 88%; two features present 96%, 72% and 91%; three features present 57%, 94% and 97%; and for the validation cohort: two features present 91%, 77% and 85%; three features present 49%, 98% and 97%.
The combined assessment of motor asymmetry, hyposmia and SN hyperechogenicity improves diagnostic specificity and allows early diagnosis of PD.
Journal of neurology, neurosurgery, and psychiatry 04/2012; 83(4):441-7. · 4.87 Impact Factor
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Prof J Volkmann,
Prof J Classen,
Prof M Naumann,
A Wolters,
Prof J Müller,
Prof R Benecke,
Germany Prof,
A A Kühn,
Prof A Kupsch,
Austria Prof, [......],
Geir Ketil Roeste,
Martin Krause,
Volker Tronnier,
Alfons Schnitzler,
Jürgen Voges,
Guido Nikkhah,
Jan Vesper,
Joseph Classen,
Markus Naumann,
Reiner Benecke
[show abstract]
[hide abstract]
ABSTRACT: Background Severe forms of primary dystonia are diffi cult to manage medically. We assessed the safety and effi cacy of pallidal neurostimulation in patients with primary generalised or segmental dystonia prospectively followed up for 5 years in a controlled multicentre trial.
The Lancet Neurology 01/2012; 11(12):1029-1038. · 23.46 Impact Factor
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[show abstract]
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ABSTRACT: In patients with deep brain stimulation (DBS), poor postoperative outcome or unexpected clinical change require brain imaging to check the lead location. Here, we studied safety, reliability and prognostic value of transcranial sonography (TCS) for DBS lead localization applying predefined TCS criteria. After measuring thermal effects of TCS and imaging artefact sizes of DBS lead using a skull phantom, we prospectively enrolled 34 patients with DBS of globus pallidus internus, ventro-intermediate thalamic or subthalamic nucleus. TCS had no influence on lead temperature, electrical parameters of DBS device or clinical state of patients. TCS measures of lead coordinates agreed with MRI measures in anterior-posterior and medial-lateral axis. Lead dislocation requiring reinsertion was reliably detected. Only patients with optimal lead position on TCS had favorable clinical 12-month outcome (>50% improvement), whereas unfavorable outcome (<25% improvement) was associated with suboptimal lead position. TCS may therefore become a first-choice modality to monitor lead location.
Ultrasound in medicine & biology 06/2011; 37(9):1382-91. · 2.02 Impact Factor
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Christoph Kamm,
Nils Uflacker,
Friedrich Asmus,
Christoph Schrader, Alexander Wolters,
Matthias Wittstock,
Jens Pahnke,
Thomas Gasser,
Jens Volkmann,
Alexander Münchau,
Johann Hagenah,
Reiner Benecke,
Christine Klein,
Katja Lohmann
Movement Disorders 06/2011; 26(11):2136-7. · 4.51 Impact Factor
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ABSTRACT: In Parkinson's disease (PD), substantia nigra hyperechogenicity (SN-h) has been related to both, local iron accumulation and microglia activation. We analysed its relationship in PD patients with serum iron (n = 31) and C-reactive protein (CRP; n = 193). SN-h correlated with lower CRP and iron levels. Also, patients with a first-degree relative with PD had lower iron levels. Microglia activation, if reflected by SN-h, may be therefore unrelated to serum CRP. Findings support the idea that SN-h indicates inherited alteration of iron metabolism.
Acta Neurovegetativa 05/2011; 119(1):53-7. · 2.73 Impact Factor
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ABSTRACT: Amyotrophic lateral sclerosis (ALS) is a progressive motor syndrome with clinical evidence of upper and lower motor neuron dysfunction. Mirror movements (MM) in ALS have been reported and attributed to a disturbed transcallosal inhibition (TI). Hence, occurrence of MM in ALS might be explained by involvement of transcallosal projecting fibre tracts into the degenerative process of the motor system. Twenty-six consecutive ALS patients were studied by clinical investigation of MM and by transcranial magnetic stimulation testing of TI using evaluation of the ipsilateral silent period. MM were observed in 39% of ALS patients. There was a significant correlation between the revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R) and occurrence of MM (correlation coefficient -0.315; p = 0.044). In conclusion, all MM patients had pathological TI at least in one hemisphere, which indicates involvement of transcallosally projecting output neurons in ALS patients, which in turn may be an early feature of the disease process with the potential of a diagnostic biomarker.
Amyotrophic Lateral Sclerosis 05/2011; 12(6):393-7. · 3.40 Impact Factor
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Kathrin Reetz,
Rebekka Lencer,
Johannes M Hagenah,
Christian Gaser,
Vera Tadic,
Uwe Walter, Alexander Wolters,
Susanne Steinlechner,
Christine Zühlke,
Katja Brockmann,
Christine Klein,
Arndt Rolfs,
Ferdinand Binkofski
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ABSTRACT: Spinocerebellar ataxia (SCA17) is a rare genetic disorder characterized by a variety of neuropsychiatric symptoms. Recently, using magnetic resonance imaging (MRI) voxel-based morphometry (VBM), several specific functional-structural correlations comprising differential degeneration related to motor and psychiatric symptoms were reported in patients with SCA17. To investigate gray matter volume (GMV) changes over time and its association to clinical neuropsychiatric symptomatology, nine SCA17 mutation carriers and nine matched healthy individuals underwent a detailed neuropsychiatric clinical examination and a high-resolution T1-weighted volume MRI scan, both at baseline and follow-up after 18 months. Follow-up images revealed a progressive GMV reduction in specific degeneration patterns. In contrast to healthy controls, SCA17 patients showed a greater atrophy not only in cerebellar regions but also in cortical structures such as the limbic system (parahippocampus, cingulate) and parietal precuneus. Clinically, progression of motor symptoms was more pronounced than that of psychiatric symptoms. Correlation with the clinical motor scores revealed a progressive reduction of GMV in cerebellar and cerebral motor networks, whereas correlation with psychiatric scores displayed a more widespread GMV impairment in frontal, limbic, parietal, and also cerebellar structures. Interestingly, changes in global functioning were correlated with bilateral atrophy within the para-/hippocampus. While there was a good temporal association between worsening of motor symptoms and progression in cerebral and cortical neurodegeneration, the progression in psychiatric related neurodegeneration seemed to be more widespread and complex, showing progressive atrophy that preceded the further development of clinical psychiatric symptoms.
The Cerebellum 12/2009; 9(2):210-7. · 3.21 Impact Factor
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ABSTRACT: Callosal dysfunction is known to be evident in a variety of neurodegenerative and inflammatory diseases of the central nervous system. Cerebral microangiopathy (CMA) may also affect callosal pathways by chronic demyelination. The aim of the present study was to investigate callosal function with respect to the extent of CMA. Callosal function was tested by a bimanual tapping task and by analysis of the ipsilateral silent period (iSP) and the transcallosal conduction time (TCT) using transcranial magnetic stimulation. Results were correlated to the extent of CMA measured by cranial magnetic resonance imaging (cMRI) in 44 patients with CMA compared to 10 control subjects. The extent of CMA was quantified by a cMRI score. Additionally, callosal atrophy was quantified by cMRI morphometry. Frequency of pathological iSP findings or disturbed bimanual tapping was significantly correlated to a higher CMA score. Moreover, the extent of CMA was significantly correlated to the degree of callosal atrophy. It is concluded that CMA considerably affects callosal pathways, possibly by chronic demyelination of callosal fibres. As the extent of CMA and atrophy of the corpus callosum is correlated to callosal dysfunction, analysis of the iSP can be used to assess the clinical impact of CMA detected by cMRI.
Journal of Neurology 11/2009; 257(4):590-7. · 3.47 Impact Factor
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ABSTRACT: 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.
Movement Disorders 07/2009; 24(10):1538-41. · 4.51 Impact Factor
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Joerg Mueller,
Inger M Skogseid,
Reiner Benecke,
Andreas Kupsch,
Thomas Trottenberg,
Werner Poewe,
Gerd H Schneider,
Wilhelm Eisner, Alexander Wolters,
J U Müller, [......],
Juliane Vollmer-Haase,
Angela Brentrup,
Martin Krause,
Volker Tronnier,
Alfons Schnitzler,
Jüergen Voges,
Guido Nikkhah,
Jan Vesper,
Markus Naumann,
Jens Volkmann
[show abstract]
[hide abstract]
ABSTRACT: As part of the first randomized, sham-stimulation controlled trial on deep brain stimulation (DBS) in primary segmental or generalized dystonia, health-related quality of life (HRQoL) was assessed by SF-36. After the 3-month sham-controlled phase, significant HRQoL improvement occurred only in the active-stimulation group. The open-label extension phase resulted in a significant improvement in all SF-36 domains following 6 months of neurostimulation. These results demonstrate a favorable impact of DBS on HRQoL in primary dystonia.
Movement Disorders 02/2008; 23(1):131-4. · 4.51 Impact Factor
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ABSTRACT: Previous investigations using transcranial magnetic stimulation (TMS) have shown that neural inhibitory motor circuits are disturbed in ADHD children. We sought to investigate the influence of methylphenidate (MPH) on inhibitory and facilitatory motor circuits of ADHD children with TMS paired pulse protocols using surplus long interval inter-stimulus intervals (ISI) not investigated so far.
Motorcortical modulation was tested with TMS paired pulse protocols employing ISI of 3, 13, 50, 100, 200, and 300 msec in 18 ADHD children before and on treatment with MPH. Clinical improvement by MPH was measured by the Conners score.
Analysis of variance (ANOVA) revealed a significant three-way interaction "Group x Amplitude x ISI," p = .001. Subsequent two-factorial ANOVAs and t-tests showed group specific differences of motor evoked potential (MEP) amplitudes for inhibitory ISIs of 3 and 100 msec, and for facilitatory ISIs of 13 and 50 msec. Compared to controls, an adjustment of these parameters by MPH could be shown. On MPH, a significant bivariate correlation was found between the Conners score reduction and averaged MEP amplitude changes only for inhibitory ISIs (3 and 100 msec).
In ADHD children, MPH modulates disturbed facilitatory and inhibitory motor circuits, which for the latter is associated with clinical improvement.
Biological Psychiatry 12/2007; 62(9):963-9. · 8.28 Impact Factor
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ABSTRACT: In several pilot studies, transcranial brain sonography findings of substantia nigra and lenticular nucleus discriminated between idiopathic Parkinson disease (PD) and atypical parkinsonian disorders.
To study the use of transcranial brain sonography in excluding the diagnosis of idiopathic PD in patients with sporadic parkinsonism.
All patients with parkinsonism admitted to our movement disorder clinic from January 1, 2003, through December 31, 2005, who fulfilled clinical diagnostic criteria for definite PD, probable parkinsonian variant of multiple-system atrophy (MSA-P), or probable progressive supranuclear palsy (PSP) were prospectively studied with transcranial brain sonography by an investigator blinded to clinical diagnoses. Patients Eligible patients included 138 with sporadic idiopathic PD (82 men and 56 women; mean +/- SD age, 67.1 +/- 9.8 years; mean +/- SD disease duration, 7.5 +/- 6.3 years; mean +/- SD motor score on the Unified Parkinson Disease Rating Scale, 32.6 +/- 18.1), 21 with MSA-P (10 men and 11 women; mean +/- SD age, 65.4 +/- 9.5 years; mean +/- SD duration of disease, 3.1 +/- 2.0 years; mean +/- SD motor score, 33.5 +/- 16.1), and 22 with PSP (13 men and 9 women; mean +/- SD age, 71.2 +/- 5.5 years; mean +/- SD duration of disease, 3.4 +/- 2.4 years; mean +/- SD motor score, 46.2 +/- 18.9). In 7 patients, transcranial brain sonography was not possible owing to insufficient temporal acoustic bone windows.
Sensitivity, specificity, and predictive value of transcranial brain sonography in indicating an atypical parkinsonian syndrome rather than idiopathic PD in patients with sporadic parkinsonism.
Normal echogenic substantia nigra indicated MSA-P rather than PD (sensitivity, 90%; specificity, 98%; positive predictive value, 86%), whereas third-ventricle dilatation of more than 10 mm in combination with lenticular nucleus hyperechogenicity indicated PSP rather than PD (sensitivity, 84%; specificity, 98%; positive predictive value, 89%). Normal echogenic substantia nigra combined with lenticular nucleus hyperechogenicity indicated MSA-P or PSP (sensitivity, 59%; specificity, 100%; positive predictive value, 100%). In parkinsonism with age at onset younger than 60 years, normal echogenic substantia nigra alone indicated MSA-P or PSP (sensitivity, 75%; specificity, 100%; positive predictive value, 100%).
Distinct transcranial brain sonography findings can exclude the diagnosis of PD in patients with sporadic parkinsonism. Sonographic discrimination of atypical parkinsonian syndromes from PD is clearer in patients with onset of parkinsonism at younger than 60 years.
Archives of Neurology 12/2007; 64(11):1635-40. · 7.58 Impact Factor
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ABSTRACT: For patients presenting predominantly or purely with tremor, the correct diagnosis of tremor-dominant Parkinson's disease (PD) versus essential tremor (ET) is very important for prognosis and effective therapy. ET tremor is usually characterized by symmetric bilateral postural and kinetic tremor, which may respond to low alcohol consumption. Many patients have a family history of ET tremors. Medical treatment with primidone or beta-blockers effectively controls ET tremor, but in many cases no treatment is needed at all. The typical tremor form of PD is an asymmetric rest tremor, which is treated with dopaminergic agents such as levodopa. Differential diagnosis of ET and PD may be difficult in a subset of PD patients who present with additional postural and kinetic tremor and in a minority of ET patients who show a clear asymmetry of their postural and kinetic tremor. In some patients with ET, the tremor can later become severe and even require treatment with deep brain stimulation.
MMW Fortschritte der Medizin 06/2007; 149 Suppl 2:94-6.
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ABSTRACT: To investigate whether transcranial brain sonography (TCS) discriminates different courses of idiopathic Parkinson's disease (PD), 101 patients with clinically definite PD were studied. In four patients, TCS was not possible due to insufficient acoustic temporal bone windows. Substantia nigra (SN) hyperechogenicity was found in 96% of assessable patients. Larger SN echogenic size correlated with younger age at PD onset (Spearman correlation, r = -0.383; P < 0.001), but not with age, PD duration, or severity. Marked bilateral SN hyperechogenicity indicated early-onset rather than late-onset PD, and akinetic-rigid (AR) or mixed-type (MX) PD rather than tremor-dominant PD. SN echogenic sizes were larger contralateral to the clinically more affected side in AR PD and MX PD patients. Reduced echogenicity of brainstem raphe was associated with depression (RR = 1.61; 95% CI = 1.05-2.46; P = 0.044) but not with other clinical features. Caudate nucleus hyperechogenicity was, independently from PD duration, related to drug-induced psychosis (RR = 2.40; CI = 1.36-4.22; P = 0.001), but not to motor fluctuations. Lenticular nucleus hyperechogenicity indicated AR PD rather than tremor-dominant PD (RR = 1.44; CI = 1.11-1.86; P = 0.040). Frontal horn dilatation > 15.4 mm (mean of bilateral measurements) indicated increased risk of dementia (RR = 4.11; CI = 1.51-11.2; P = 0.001). We conclude that TCS displays characteristic changes of deep brain structures in different clinical manifestations of PD.
Movement Disorders 01/2007; 22(1):48-54. · 4.51 Impact Factor
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Andreas Kupsch,
Reiner Benecke,
Jörg Müller,
Thomas Trottenberg,
Gerd-Helge Schneider,
Werner Poewe,
Wilhelm Eisner, Alexander Wolters,
Jan-Uwe Müller,
Günther Deuschl, [......],
Juliane Vollmer-Haase,
Angela Brentrup,
Martin Krause,
Volker Tronnier,
Alfons Schnitzler,
Jürgen Voges,
Guido Nikkhah,
Jan Vesper,
Markus Naumann,
Jens Volkmann
[show abstract]
[hide abstract]
ABSTRACT: Neurostimulation of the internal globus pallidus has been shown to be effective in reducing symptoms of primary dystonia. We compared this surgical treatment with sham stimulation in a randomized, controlled clinical trial.
Forty patients with primary segmental or generalized dystonia received an implanted device for deep-brain stimulation and were randomly assigned to receive either neurostimulation or sham stimulation for 3 months. The primary end point was the change from baseline to 3 months in the severity of symptoms, according to the movement subscore on the Burke-Fahn-Marsden Dystonia Rating Scale (range, 0 to 120, with higher scores indicating greater impairment). Two investigators who were unaware of treatment status assessed the severity of dystonia by reviewing videotaped sessions. Subsequently, all patients received open-label neurostimulation; blinded assessment was repeated after 6 months of active treatment.
Three months after randomization, the change from baseline in the mean (+/-SD) movement score was significantly greater in the neurostimulation group (-15.8+/-14.1 points) than in the sham-stimulation group (-1.4+/-3.8 points, P<0.001). During the open-label extension period, this improvement was sustained among patients originally assigned to the neurostimulation group, and patients in the sham-stimulation group had a similar benefit when they switched to active treatment. The combined analysis of the entire cohort after 6 months of neurostimulation revealed substantial improvement in all movement symptoms (except speech and swallowing), the level of disability, and quality of life, as compared with baseline scores. A total of 22 adverse events occurred in 19 patients, including 4 infections at the stimulator site and 1 lead dislodgment. The most frequent adverse event was dysarthria.
Bilateral pallidal neurostimulation for 3 months was more effective than sham stimulation in patients with primary generalized or segmental dystonia. (ClinicalTrials.gov number, NCT00142259 [ClinicalTrials.gov].).
New England Journal of Medicine 12/2006; 355(19):1978-90. · 53.30 Impact Factor
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ABSTRACT: Neuronal plasticity is to be kept within operational limits to serve its purpose as a safe memory system that shapes and focuses sensory and motor representations. Temporal and spatial properties of motor cortical plasticity were assessed in patients with writer's cramp using a model of long-term potentiation (LTP) and long-term depression (LTD) of synaptic efficacy. Paired associative stimulation (PAS) combined repetitive electric stimulation of the median or ulnar nerve (MN or UN) with subsequent transcranial magnetic stimulation of the contralateral dominant motor cortex at 21.5 ms (MN-PAS21.5; UN-PAS21.5) or 10 ms (MN-PAS10). Motor-evoked potentials were recorded from abductor pollicis brevis (APB) muscle and abductor digiti minimi (ADM) muscles in 10 patients with writer's cramp and 10 matched healthy control subjects. Following MN-PAS21.5 or UN-PAS21.5 in non-dystonic subjects, motor responses increased if the afferent PAS-component came from a homologous peripheral region and remained stable with a non-homologous input. In contrast, following either MN-PAS21.5 or UN-PAS21.5, both APB- and ADM-amplitudes increased in patients. Compared with controls, this increase started earlier, its magnitude was larger and its duration longer. Following MN-PAS10 in controls, APB-amplitudes decreased, while ADM-amplitudes increased. In writer's cramp, the decrease of APB-amplitudes started earlier and lasted longer. Of note, ADM-amplitudes were decreased, too. LTP-like as well as LTD-like plasticity is abnormal with respect to both gain and spatial organization. These findings may help to develop a pathophysiological model explaining core features of focal dystonia.
Brain 11/2006; 129(Pt 10):2709-21. · 9.46 Impact Factor
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ABSTRACT: To study the use of transcranial sonography (TCS) in discriminating between patients with dementia with Lewy bodies (DLB) and Parkinson's disease with dementia (PDD).
Fourteen patients with DLB, 31 with PDD and 73 with PD without dementia (PDnD) were studied with TCS.
All assessable patients with DLB, 97% with PDD, and 94% with PDnD showed at least unilateral hyperechogenicity of substantia nigra (SN). However, bilateral marked SN hyperechogenicity was present in 80% of DLB patients but only in one third of PDD and PDnD patients, and was associated with younger age at disease onset in PD but not in DLB. An asymmetry index > or = 1.15 of bilateral SN echogenic sizes, estimated by division of larger size by smaller size, was found in 69% of PDD patients but only 20% of DLB patients. Combination of SN echogenic sizes, asymmetry indices and onset age discriminated PDD from DLB with a sensitivity of 96%, a specificity of 80% and a positive predictive value of 93%. TCS of brainstem raphe, thalami, lenticular nuclei, caudate nuclei and ventricle widths did not discriminate between DLB and PDD. Compared with PDnD patients, DLB and PDD patients exhibited significantly larger widths of third ventricle and of frontal horns. In PDD patients, scores on the Unified Parkinson's Disease Rating Scale correlated with widths of third ventricle and of frontal horns.
SN hyperechogenicity is typical for PDD and DLB. However, size, asymmetry and relation of SN hyperechogenicity to age at disease onset discriminate PDD from DLB.
Journal of Neurology 04/2006; 253(4):448-54. · 3.47 Impact Factor
