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ABSTRACT: Progressive supranuclear palsy (PSP) is the most common atypical parkinsonian syndrome and an important differential diagnosis of parkinson's disease (PD). The clinical diagnosis of PSP relies on characteristic symptoms. There is evidence of clinical subgroups within the entity of PSP interfering with making the firm diagnosis. It was the aim of the study to clarify the differences between phenotypical subtypes of PSP and PD focusing on transcallosal inhibition (TI). A systematic chart review of 67 patients supposed to have probable PSP was done in a standardized diagnostic work-up. As only complete data sets were included into further analysis, 26 PSP patients (mean age 68.6 ± 7.1 years) could be evaluated and subdivided into Richardson's syndrome (RS) (n = 15) or PSP of parkinsonian type (PSP-P) (n = 11). Fifteen PD patients served as controls. TI was evaluated by investigation of the ipsilateral silent period (iSP) with transcranial magnetic stimulation (TMS). Cognition was assessed by the Addenbrooke's cognitive examination (ACE-R). TMS revealed a significantly more severe affection of TI in RS patients as compared to PSP-P and PD patients who showed similar neurophysiological findings. 47 % of RS patient displayed an iSP loss, whereas PSP-P and PD did not. There was a significant correlation between iSP latency and ACE-R (Spearman's coefficient -0.369, P = 0.010). In conclusion, RS patients-contrary to PSP-P and PD patients-had pathological TI at least in one hemisphere indicating more severe involvement of transcallosally projecting output neurons in RS.
Acta Neurovegetativa 08/2012; · 2.73 Impact Factor
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ABSTRACT: A 16- year-old boy with long-standing severe Tourette syndrome (TS) and mental retardation, non-responsive to complex pharmocological and behavioural treatment was selected for bilateral deep brain stimulation (DBS) of the globus pallidus internus (GPi). Pre-operative and post-operative Yale Tourette syndrome scale (YTSS) scores and several other scores were used to quantify the effect of DBS up to one year follow-up. Although subscores of the YTSS improved, the overall outcome of chronic GPi-DBS showed no substantial therapeutic effect. This finding is in contrast to markedly improved TS of the only two adolescent TS patients in whom DBS has been performed so far. In this article we discuss possible reasons for the poor therapeutic effect of GPi-DBS in our patient contributing to the on-going debate on DBS inclusion criteria for adolescent TS patients.
Neuropediatrics 10/2009; 40(5):239-42. · 0.94 Impact Factor
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A Wolters
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ABSTRACT: In patients with primary generalized or segmental dystonia controlled studies have shown that bilateral pallidal deep brain stimulation (DBS) can reduce disability scores by 40 to 60 %. Up to now, the data base on the therapeutic effects of DBS in selected patients with focal dystonia is less extensive. Long-term efficacy of DBS in dystonia has been demonstrated, but reports have focused mainly on patients with primary generalized dystonia so far, with a mean observation period of approximately 5 years. Predictors of a favourable long-term efficacy of DBS in primary generalized dystonia patients are young age at surgery, a shorter duration of the disease, a lower severity of disability, and a posteroventrolateral localization of the DBS electrode within the globus pallidus internus (GPi). Controlled studies are needed to identify also the factors determining the best long-term outcome of non-generalized dystonia patients treated with DBS.
Fortschritte der Neurologie · Psychiatrie 08/2009; 77 Suppl 1:S61-3. · 0.74 Impact Factor
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ABSTRACT: Assessment of upper motor neuron (UMN) involvement is essential for the diagnosis of amyotrophic lateral sclerosis (ALS). In a number of ALS cases, mirror movements (MM) suggest an involvement of transcallosal fibre tracts in conjunction with UMN involvement. The present study analysed whether deficient transcallosal inhibition (TI) tested by TMS enables detection of cortical affection in ALS, even at early stages of the disease.
In three patients with definite ALS and 12 patients with early ALS (aged 64.1+/-7.8 years) TMS investigation included analysis of contralateral (cMEP) and ipsilateral (iMEP) motor evoked potentials as well as measurement of TI (latency, duration) with recording from both first dorsal interosseus muscles.
Clinical UMN signs were present in four patients. 83.3% of patients showed a pathological TI (prolongation or loss of TI). Five out of eight ALS patients showing a pathological TI had no clinical UMN signs. Two of these patients showed MM. One patient displayed also pathological findings in TI investigation.
Our findings suggest a functional deficit of transcallosal fibre tracts even at early stages of the disease still lacking clinical UMN signs.
Measurement of TI tested by TMS can detect an involvement of the cortical output system in ALS and may be helpful in an early assessment of the diagnosis.
Clinical Neurophysiology 03/2007; 118(2):301-7. · 3.41 Impact Factor
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ABSTRACT: Urinary dysfunction is very common in idiopathic Parkinson's disease (PD) and manifests primarily with symptoms of overactive bladder (OAB). Affection of central serotonergic systems has been suggested to play a role in OAB. The objective of this study was to evaluate whether in PD patients with OAB symptoms a specific alteration of the brainstem raphe (BR), which contains serotonergic neurons, can be detected with transcranial sonography (TCS). Of 116 PD patients enrolled, 19 had PD-related OAB symptoms (OAB+) unlike remaining 97 patients (OAB-). Patients were examined by a sonographer blinded to the clinical data. Reduced echogenicity of BR was found in 12 (63%) OAB+ patients but only in 18 (19%) of 93 assessable OAB- patients (Mann-Whitney U-test, P < 0.001). In OAB+ patients, lower raphe echogenicity score was associated with longer duration of OAB symptoms (anova, P = 0.033). Other TCS findings such as echogenicity of substantia nigra, thalami, lenticular and caudate nuclei, and widths of third and lateral ventricles did not differ between OAB+ and OAB- patients. TCS findings suggest a pathogenetic role of BR in OAB related to PD. Alterations may reflect disturbance of its central serotonergic system.
European Journal of Neurology 12/2006; 13(12):1291-7. · 3.69 Impact Factor
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ABSTRACT: Motor hyperactivity is one of the most outstanding symptoms of attention deficit hyperactivity disorder (ADHD) which might be caused by a disturbed inhibitory motor control. Using focal transcranial magnetic stimulation (TMS) we tested the cortico-callosal inhibition (duration and latency of the ipsilateral Silent Period, iSP) in 23 children with ADHD (mean age 11+/-2.6 years) before and on treatment with methylphenidate (MPH). iSP latency was age correlated, whereas iSP duration as well as Conners scores were age independent. Analyses of mean differences revealed a significant prolongation of iSP duration (p=0.001), shortening of iSP latency (p=0.027) and reduction of Conners score (p=0.001) under medication. Increase of iSP duration and reduction of Conners score under medication were significantly correlated (t=-9.87, p=0.016). Reduced iSP duration and prolonged iSP latency in ADHD children could be the result of a disturbed transcallosally mediated inhibition, most probable due to a combination of maturation deficits of callosal fiber tracts as well as neuronal synaptical transmission within the neuronal network between ipsilaterally stimulated cortex layer III--the origin of transcallosal motor-cortical fibers--and contralateral layer V, the origin of the pyramidal tract. MPH may indirectly improve the dysbalance between excitatory and inhibitory interneuronal activities of this neuronal network via dopaminergic modulatory effects of the striato-thalamo-cortical loop.
Neuroscience Letters 10/2006; 405(1-2):14-8. · 2.11 Impact Factor
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ABSTRACT: To study the use of brain parenchyma sonography (BPS) in discriminating between patients with corticobasal degeneration (CBD) and progressive supranuclear palsy (PSP).
Thirteen patients with PSP and eight with CBD were studied with BPS according to a standardized protocol.
Seven (88%) of the eight CBD patients showed marked hyperechogenicity of the substantia nigra (SN) but none of eleven PSP patients (Mann-Whitney U test, p < 0.001). This finding indicated CBD with a positive predictive value of 100%. Marked dilatation of the third ventricle (width > 10 mm) was found in 10 (83%) of 12 PSP patients, but in none of the CBD patients (p < 0.005). BPS measurements of ventricle widths closely matched MRI measurements (Pearson correlation, r = 0.90, p < 0.001). The presence of at least one of the BPS findings 1) marked SN hyperechogenicity and 2) third-ventricle width < 10 mm indicated CBD with a sensitivity of 100%, a specificity of 83%, and a positive predictive value of 80%. Other BPS findings such as echogenicity of lentiform and caudate nuclei and widths of the frontal horns did not discriminate between CBD and PSP. One PSP patient could not be assessed because of insufficient acoustic temporal bone windows.
Substantia nigra hyperechogenicity, reported earlier as characteristic brain parenchyma sonography finding in idiopathic Parkinson disease, is also typical for corticobasal degeneration.
Neurology 09/2004; 63(3):504-9. · 8.31 Impact Factor
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ABSTRACT: The aim of this study was to investigate mechanisms of motor-cortical excitability and inhibition which may contribute to motor hyperactivity in children with attention deficit hyperactivity disorder (ADHD).
Using transcranial magnetic stimulation (TMS), involvement of the motor cortex and the corpus callosum was analysed in 13 children with ADHD and 13 sex- and age-matched controls. Contralateral silent period (cSP) and transcallosally mediated ipsilateral silent period (iSP) were investigated.
Resting motor threshold (RMT), amplitudes of motor evoked potentials (MEP) and cSP were similar in both groups whereas iSP-latencies were significantly longer (p<0.05) and their duration shorter (p<0.01) in the ADHD group. For the ADHD group iSP duration tended to increase and iSP latency to decrease with age (n.s.). Conners-Scores did neither correlate with iSP-latencies and -duration nor with children's age.
The shortened duration of iSP in ADHD children could be explained by an imbalance of inhibitory and excitatory drive on the neuronal network between cortex layer III-the projection site of transcallosal motor-cortical fibers-and layer V, the origin of the pyramidal tract. The longer iSP-latencies might be the result of defective myelination of fast conducting transcallosal fibers in ADHD. iSP may be a useful supplementary diagnostic tool to discriminate between ADHD and normal children.
Clinical Neurophysiology 11/2003; 114(11):2036-42. · 3.41 Impact Factor
