U Walter

Universität Rostock, Rostock, Mecklenburg-Vorpommern, Germany

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Publications (12)53.39 Total impact

  • Article: Sonographic detection of basal ganglia abnormalities in spasmodic dysphonia.
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    ABSTRACT: BACKGROUND AND PURPOSE: Abnormalities of the lenticular nucleus (LN) on transcranial sonography (TCS) are a characteristic finding in idiopathic segmental and generalized dystonia. Our intention was to study whether TCS detects basal ganglia abnormalities also in spasmodic dysphonia, an extremely focal form of dystonia. METHODS: Transcranial sonography of basal ganglia, substantia nigra and ventricles was performed in 14 patients with spasmodic dysphonia (10 women, four men; disease duration 16.5 ± 6.1 years) and 14 age- and sex-matched healthy controls in an investigator-blinded setting. RESULTS: Lenticular nucleus hyperechogenicity was found in 12 spasmodic dysphonia patients but only in one healthy individual (Fisher's exact test, P < 0.001) whilst other TCS findings did not differ. The area of LN hyperechogenic lesions quantified on digitized image analysis correlated with spasmodic dysphonia severity (Spearman test, r = 0.82, P < 0.001). CONCLUSION: Our findings link the underlying pathology of spasmodic dysphonia to that of more widespread forms of dystonia.
    European Journal of Neurology 04/2013; · 3.69 Impact Factor
  • Article: Interhemispheric inhibition in different phenotypes of progressive supranuclear palsy.
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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
  • Article: [Experience with Levetiracetam in the Treatment of Status Epilepticus.]
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    ABSTRACT: Non-convulsive status epilepticus and epilepsia partialis continua are common epileptic conditions for which straightforward recommendations based on controlled randomised trials for treatment of therapy refractory courses are lacking. Therefore in these conditions sometimes antiepileptic drugs that are not approved by governmental authorities for the treatment of status epilepticus (SE) are used. Here we review all case reports and case series concerning the treatment of SE with levetiracetam (LEV), that had been listed in pub-med up to December 12th 2011. Additionally we analysed abstracts and papers in peer reviewed journals, that were listed in the references of the primarily reviewed papers. Furthermore we looked for LEV treatments in papers on the use of lacosamide (LCM) in SE. LEV was given in dosages ranging from 500 mg to 9000 mg per day. Side effects were especially sedation and irritability. Estimated on the basis of the case series the overall success-rate of LEV in terminating status epilepticus may be set in a range between 53.7 % and 58.1 %. Therefore LEV may be a useful alternative for the treatment of SE when the approved drugs are contraindicated or when these drugs have been taken without success.
    Fortschritte der Neurologie · Psychiatrie 08/2012; · 0.74 Impact Factor
  • Article: Insular stroke is associated with acute sympathetic hyperactivation and immunodepression.
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    ABSTRACT: BACKGROUND AND PURPOSE: Post-stroke immunodepression has been related to brain lesion size but not a specific lesion location. Here, we studied the influence of lesion location within middle cerebral artery (MCA) territory on parameters related to activation of sympathetic adrenomedullar pathway, immunodepression, and associated infection. METHODS: We analyzed clinical, brain imaging, and laboratory data of 384 patients (174 women; mean age 70.8 ± 12.9 years) consecutively admitted to the stroke unit no later than 24 h after onset of acute ischaemic stroke involving the MCA territory. RESULTS: Patients with lesion affecting >33% of MCA territory had increased serum metanephrine and normetanephrine levels, elevated neutrophil counts but decreased eosinophil, helper T lymphocyte, and cytotoxic T lymphocyte counts compared to patients with lesion in <33% of MCA territory. Patients with large infarctions had increased frequency of infections within 14 days after stroke, especially chest infections (P < 0.001). Considering only patients with non-lacunar infarction in <33% of MCA territory, those with insular lesion had significantly higher normetanephrine levels, higher neutrophil but lower eosinophil and helper T lymphocyte counts than those with non-insular lesion, despite similar lesion diameters. This coincided with an increased frequency of chest infections (P < 0.01) in patients with insular lesion. Whilst patients with right insular lesion showed decreased heart rate variability, lesion laterality had no impact on laboratory findings or infection frequency. CONCLUSION: These findings suggest a specific role of insular lesion in the pathogenesis of stroke-induced sympathetic hyperactivation and immunodepression. Neuroimaging studies applying lesion volume calculation techniques are warranted to confirm these findings.
    European Journal of Neurology 07/2012; · 3.69 Impact Factor
  • Article: Recurrent aphasic status epilepticus after prolonged generalized tonic-clonic seizures versus a special feature of Todd's paralysis.
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    ABSTRACT: Postictal aphasia may be a feature of Todd's paralysis or the presentation of aphasic nonconvulsive status epilepticus (NCSE). We describe a 74-year-old woman with three episodes of aphasic status epilepticus after prolonged generalized tonic-clonic seizures. In the first episode, the NCSE was not definitively diagnosed, but an increase in the epileptic medication led to resolution of the epileptic activity within 2 weeks. During the second episode, NCSE was terminated within 7 days under intensified antiepileptic treatment. In the third episode, phenytoin treatment led to intoxication and resulted in further treatment on an intensive care unit. The patient required several months to recover from this episode. NCSE in the elderly is difficult to recognize, especially when it presents as a prolonged postictal deficit like aphasia. Once diagnosed it has to be treated carefully, because in the elderly, aggressive treatment strategies may be associated with a high risk of adverse events.
    Epilepsy & Behavior 01/2011; 20(1):132-7. · 2.34 Impact Factor
  • Article: Transcranial brain sonography findings predict disease progression in multiple sclerosis.
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    ABSTRACT: In multiple sclerosis (MS), an early neurodegenerative affection of subcortical gray matter has been suggested. Transcranial sonography (TCS) shows hyperechogenic lesions of substantia nigra (SN) and basal ganglia, thought to reflect iron accumulation, in a number of primary neurodegenerative diseases. The present study deals with the question of whether TCS can also display deep gray matter lesions in patients with MS and whether sonographic findings relate to severity and progression of MS. We prospectively studied 75 patients with different courses of MS and 55 age-matched healthy subjects clinically and with TCS. Twenty-three patients additionally had 1.5-T MRI at the time of TCS. Disease progression was assessed clinically 2 years after TCS. Abnormal hyperechogenicity of SN, lenticular nucleus (LN), caudate nucleus, and thalamus was found in 41%, 54%, 40%, and 8% of the patients with MS, with similar frequency in patients with relapsing-remitting and primary or secondary progressive MS if corrected for disease duration, but only in 13%, 13%, 5% (each, p < 0.001), and none (p = 0.028) of the control subjects. Hyperechogenicity of SN and LN correlated with more pronounced MRI T2 hypointensity, thought to reflect iron deposition. Larger bilateral SN echogenic area was related to higher rate of disease progression, whereas small SN echogenic area (SN hypoechogenicity) predicted a disease course without further progression within 2 years. Neurodegenerative disease-like deep gray matter lesions can be frequently detected by transcranial sonography (TCS) in patients with multiple sclerosis (MS). Findings suggest that TCS shows changes of brain iron metabolism which correlate with future progress of MS.
    Neurology 08/2009; 73(13):1010-7. · 8.31 Impact Factor
  • Article: Overactive bladder in Parkinson's disease: alteration of brainstem raphe detected by transcranial sonography.
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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
  • Article: Sonographic detection of basal ganglia lesions in asymptomatic and symptomatic Wilson disease.
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    ABSTRACT: To investigate whether transcranial brain parenchyma sonography (TCS) detects basal ganglia abnormalities in asymptomatic and symptomatic patients with Wilson disease (WD) and whether findings correlate with disease severity. Twenty-one patients with WD with (n = 18) or without (n = 3) neurologic symptoms were investigated. Disease severity was assessed by three independent neurologists using a WD rating scale (WDRS) with the items dysarthria, akinesia, ataxia, tremor, and dystonia; the raters' median score was used for further analysis. Basal ganglia TCS was performed according to a standardized protocol. TCS revealed lenticular nucleus (LN) hyperechogenicity in all assessable neurologically symptomatic and in two of the three asymptomatic patients. Size of LN hyperechogenic area correlated with the WDRS score (Spearman correlation, rho = 0.604, p = 0.006), as did the size of thalamus hyperechogenic area (n = 7, rho = 0.891, p = 0.007), the width of third ventricle (n = 21, rho = 0.613, p = 0.003), and the width of lateral ventricles (n = 20, rho = 0.642, p < 0.001). Substantia nigra hyperechogenicity, detected in 10 patients, did not correlate with disease severity. There was no correlation between age at disease onset or disease duration and any TCS finding. Of the 19 patients with LN hyperechogenicity, only 12 showed abnormal LN on MRI. Transcranial brain parenchyma sonography (TCS) detects lenticular nucleus hyperechogenicity, likely to be caused by copper accumulation, in neurologically symptomatic and asymptomatic Wilson disease (WD). TCS findings correlate with disease severity. TCS appears a promising tool for disease monitoring in WD.
    Neurology 05/2005; 64(10):1726-32. · 8.31 Impact Factor
  • Article: Sonographic discrimination of corticobasal degeneration vs progressive supranuclear palsy.
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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
  • Article: [Anticoagulation in stroke. Evidence-based and empirical indications].
    DMW - Deutsche Medizinische Wochenschrift 11/2003; 128(42):2200-5. · 0.53 Impact Factor
  • Article: Brain parenchyma sonography discriminates Parkinson's disease and atypical parkinsonian syndromes.
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    ABSTRACT: To study the use of brain parenchyma sonography (BPS) in discriminating between patients with idiopathic PD (IPD) and atypical parkinsonian syndromes (APS). Twenty-five patients with APS, 9 with progressive supranuclear palsy (PSP) and 16 with multiple-system atrophy (MSA), and 25 age-matched patients with IPD were prospectively studied with BPS according to a standardized protocol. Twenty-four of the 25 (96%) IPD patients exhibited hyperechogenicity of the substantia nigra (SN) but only 2 of 23 (9%) APS patients (Mann-Whitney U test, p < 0.001). In those two APS patients, SN hyperechogenicity was moderate only, whereas the remaining 21 APS patients had normal SN echogenicity. The specificity of SN hyperechogenicity in detection of clinically diagnosed IPD patients was 96%, and the sensitivity was 91%. If SN hyperechogenicity was marked, APS could be excluded because of a positive predictive value of 100% for IPD. Nucleus lentiformis hyperechogenicity was found in 17 of 22 (77%) APS patients but in only 5 of 22 (23%) IPD patients (Mann-Whitney U test, p < 0.001). Nucleus caudatus and thalamus echogenicity and widths of the third ventricle and of the frontal horns of the lateral ventricles did not discriminate between IPD and APS. Two patients with PSP could not be assessed because of an insufficient bone window. BPS is a novel and noninvasive method to differentiate highly specifically between IPD and APS. Therefore, BPS might become a standard investigation in parkinsonian disorders.
    Neurology 01/2003; 60(1):74-7. · 8.31 Impact Factor
  • Article: Substantia nigra echogenicity is normal in non-extrapyramidal cerebral disorders but increased in Parkinson's disease.
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    ABSTRACT: Transcranial sonography (TCS) revealed substantia nigra (SN) hyperechogenicity in idiopathic Parkinson's disease (IPD). To further evaluate specificity of this finding, we examined 30 IPD patients and 30 age-matched subjects with non-extrapyramidal cerebral disorders (NED). All IPD patients showed a SN hyperechogenicity, in 17 it was bilateral and in 13 unilateral. 7 NED patients had a SN hyperechogenicity, in all it was unilateral, confirming previous results in healthy subjects. Bilateral SN hyperechogenicity indicates IPD and normal SN echogenicity indicates NED. In 30% of patients TCS does not distinguish between IPD and NED. Data further support the assumption that bilateral SN hyperechogenicity is specific for IPD.
    Acta Neurovegetativa 03/2002; 109(2):191-6. · 2.73 Impact Factor