Hans Holthausen

Universitätsklinikum Erlangen, Erlangen, Bavaria, Germany

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Publications (18)77.86 Total impact

  • Source
    Article: Neuropathologic measurements in focal cortical dysplasias: validation of the ILAE 2011 classification system and diagnostic implications for MRI.
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    ABSTRACT: Focal cortical dysplasias (FCD) which represent a composite group of cortical malformations are increasingly recognized as morphological substrate for severe therapy-refractory epilepsy in children and young adults. However, presurgical evaluation remains challenging as not all FCD variants can be reliably detected by high-resolution magnetic resonance imaging (MRI). Here, we studied a cohort of 52 epilepsy patients with neuropathological evidence for FCD using the 2011 classification of the International League against Epilepsy (ILAE) and systematically analysed those histopathologic features applicable also for MRI diagnostics. Histopathologic parameters included quantitative measurements of cellular profiles, cortical thickness, heterotopic neurons in white matter, and myelination that were compared between FCD subtypes and age-/localization-matched controls (n = 36) using multivariate analysis. Dysmorphic neurons in both FCD Type II variants showed significantly increased diameter of their cell bodies and nuclei. Cortical thickness was also increased with a distinct loss of myelin content specifying FCD Type IIb from IIa. The data further suggested that myelination deficits in FCD Type IIb result from compromised oligodendroglial lineage differentiation and we concluded that the "transmantle sign" is a unique finding in FCD Type IIb. In contrast, FCD Type Ia was characterized by a smaller cortical ribbon and higher neuronal densities, but these parameters failed to reach statistical significance (considering age- and location-dependent variability in controls). All FCD variants showed abnormal grey-white matter boundaries with increased numbers of heterotopic neurons. Similar results were obtained also at deep white matter location. Thus, many FCD variants may indeed escape visual MRI inspection, but suspicious areas with increased or decreased cortical thickness as well as grey-white matter blurring may be uncovered using post-processing protocols of neuroimaging data. The systematic analysis of well-specified histopathological features could be helpful to improve sensitivity and specificity in MRI detection during pre-surgical work-up of patients with drug-resistant focal epilepsies.
    Acta Neuropathologica 11/2011; 123(2):259-72. · 9.32 Impact Factor
  • Article: A retrospective study of the relation between vaccination and occurrence of seizures in Dravet syndrome.
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    ABSTRACT: Dravet syndrome is a severe epileptic encephalopathy starting in the first year of life. Mutations in SCN1A can be identified in the majority of patients, and epileptic seizures in the setting of fever are a clinical hallmark. Fever is also commonly seen after vaccinations and provocation of epileptic seizures by vaccinations in patients with Dravet syndrome has been reported, but not systematically assessed. In a retrospective evaluation of 70 patients with Dravet syndrome and SCN1A mutations, seizures following vaccinations were reported in 27%. In 58% of these patients vaccination-related seizures represented the first clinical manifestation. The majority of seizures occurred after DPT vaccinations and within 72 h after vaccination. Two-thirds of events occurred in the context of fever. Our findings highlight seizures after vaccinations as a common feature in Dravet syndrome and emphasize the need for preventive measures for seizures triggered by vaccination or fever in these children.
    Epilepsia 01/2011; 52(1):175-8. · 3.96 Impact Factor
  • Article: Clinical functional MRI of the language domain in children with epilepsy.
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    ABSTRACT: Functional MRI (fMRI) for the assessment of language functions is increasingly used in the diagnostic workup of patients with epilepsy. Termed "clinical fMRI," such an approach is also feasible in children who may display specific patterns of language reorganization. This study was aimed at assessing language reorganization in pediatric epilepsy patients, using fMRI. We studied 26 pediatric epilepsy patients (median age, 13.05 years; range, 5.6-18.7 years) and 23 healthy control children (median age, 9.37 years; range, 6.2-15.4 years), using two child-friendly fMRI tasks and adapted data-processing streams. Overall, 81 functional series could be analyzed. Reorganization seemed to occur primarily in homotopic regions in the contralateral hemisphere, but lateralization in the frontal as well as in the temporal lobes was significantly different between patients and controls. The likelihood to find atypical language organization was significantly higher in patients. Additionally, we found significantly stronger activation in the healthy controls in a primarily passive task, suggesting a systematic confounding influence of antiepileptic medication. The presence of a focal cortical dysplasia was significantly associated with atypical language lateralization. We conclude that important confounds need to be considered and that the pattern of language reorganization may be distinct from the patterns seen in later-onset epilepsy.
    Human Brain Mapping 12/2010; 32(11):1882-93. · 5.88 Impact Factor
  • Article: Why one task is not enough: functional MRI for atypical language organization in two children.
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    ABSTRACT: Functional MRI is increasingly used to determine the hemispheric dominance for language. This is especially relevant in children who may not be able to comply with the high demands of a Wada test. We here report on two children in which the full extent of language reorganization was only determined when two fMRI tasks were analyzed; in the first case, the results from the second task corroborated the shifted hemispheric dominance seen in the first task. In the second case, the second task showed an opposite hemispheric dominance, suggesting a hemispheric dissociation of language functions. These cases underline the necessity to use more than one fMRI task for the determination of hemispheric dominance, whenever possible. This is particularly relevant in children as unusual patterns of reorganization may be more likely.
    European journal of paediatric neurology: EJPN: official journal of the European Paediatric Neurology Society 11/2010; 14(6):474-8. · 2.01 Impact Factor
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    Article: A distinct variant of focal cortical dysplasia type I characterised by magnetic resonance imaging and neuropathological examination in children with severe epilepsies.
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    ABSTRACT: Focal Cortical Dysplasias (FCDs) present with a large clinicopathological spectrum. FCDs are believed to relate directly to an epileptogenic condition, although seizure control by surgical resection is variable. This applies in particular to young children with multilobar FCDs, suffering from severe epilepsies and psychomotor retardation. Herein, we performed a comparative analysis of presurgically available data and microscopic inspection of resected cortical specimens to further characterise the pathomorphological spectrum of FCD. Multilobar resection procedures were performed in a consecutive series of 18 young children (mean 7.6 years) with severe pharmaco-resistant epilepsies following extensive presurgical surface-/invasive video-EEG monitoring intraoperative electro-corticography (iECoG), as well as high resolution MRI. In all cases, systematic neuropathological examination of surgical specimens was performed with respect to architectural abnormalities and cell density measurements. These histomorphological data were compared with volumetric MRI analysis. Histopathological examination revealed increased neuronal densities correlating with decreased cortical thickness and abundance of neuronal microcolumns in all cases. Intriguingly, the affected cerebral hemisphere was significantly smaller, relative to the non-epileptogenic contralateral side, in 16 children of our patient series. In conclusion, hypoplastic neocortex and columnar architectural disorganisation point to compromised cortical development, and appear as distinct FCD I subtype in children suffering from severe epilepsies and psychomotor retardation.
    Epileptic disorders: international epilepsy journal with videotape 09/2010; 12(3):172-80. · 1.50 Impact Factor
  • Article: Increased frequency of distinct TSC2 allelic variants in focal cortical dysplasias with balloon cells and mineralization
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    ABSTRACT: Focal cortical dysplasias with balloon cells (FCDIIb) usually present with characteristic imaging and molecular features, that is, a transmantle sign on fluid-attenuated inversion recovery MRI and abundance of allelic variants of the tuberous sclerosis gene 1 (TSC1). Recently, we observed several mineralized lesions (n = 5) lacking this MRI pattern and which surprisingly turned out as FCDIIb upon neuropathological examination. These mineralized FCDIIb revealed an increased frequency of TSC2 allelic variants but not TSC1 (intron 31: 60% vs. 11% in controls; P = 0.0164, exon 41: 40% vs. 6.5% in controls; P = 0.0441). Mineralized FCDIIb have a favorable postsurgical outcome and need consideration in the presurgical differential diagnosis of calcified lesions associated with pharmacoresistant focal epilepsies.
    Neuropathology 04/2009; 29(5):559 - 565. · 2.02 Impact Factor
  • Article: Different presurgical characteristics and seizure outcomes in children with focal cortical dysplasia type I or II.
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    ABSTRACT: Cortical dysplasia (FCD) is a frequent cause of epilepsy in childhood. Two major pathological variants are distinguished, FCD type I and II. The aim of the study was to characterize differences between FCD type I and II with respect to imaging and EEG findings, clinical and neuropsychological presentations, and surgical outcome. Forty children with refractory epilepsy and histopathologically confirmed FCD were retrospectively analyzed. FCD type I was identified in 24 and FCD type II in 16 patients. Characteristic MRI abnormalities in FCD type I included subtle white matter signal changes and regional reduction of the white matter volume. Typical MRI findings in FCD type II were increased cortical thickness, transmantle sign, gray-white matter junction blurring, fluid-attenuated inversion recovery (FLAIR) and proton density (PD) gray matter signal changes as well as T1w, and PD white matter signal changes. Continuous EEG slowing was significantly more common in patients with FCD type I. Children with FCD type I presented with lower levels of intelligence and were suffering more often from maladaptive behavior and behavioral disorders. Surgical outcome was significantly worse in the FCD type I group (seizure freedom was achieved in 21% FCD type I patients and in 75% FCD type II subjects, p < 0.001). Clinically important differences were found in children with distinct histopathological subtypes of FCD. Due to prominent neuropsychological deficits and worse seizure outcome, treatment strategies in FCD type I are more challenging than previously reported and these children should be recognized and specifically addressed within the incoherent group of patients with malformative brain disorders.
    Epilepsia 06/2008; 50(1):125-37. · 3.96 Impact Factor
  • Article: White matter angiopathy is common in pediatric patients with intractable focal epilepsies.
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    ABSTRACT: The blood-brain barrier (BBB) and functional organization of blood vessels is severely affected in many epilepsy disorders. This was repetitively shown with respect to the cause, effect and treatment of seizures. In the present study, we investigated pathomorphological abnormalities of blood vessels in a cohort of young patients with chronic intractable seizures submitted to an epilepsy surgery program. Histopathological examination was performed in surgical specimens obtained from 87 children with intractable epilepsies. Immunohistochemistry was employed to further characterize the basal membrane as well as specific cellular and tissue reactions. Pathological findings were correlated with clinical data including antiepileptic drug prescription. We identified an intriguing pattern of white matter angiopathy in 64.4% of our patient cohort. Major alterations included splitting of the basal membrane into endothelial and parenchymal leaves, which was restricted to arterioles and capillaries of the white matter and resulted in an extensively enlarged perivascular space. These cavities contained numerous blood cells and showed a spongiform appearance at the ultrastructural level. Angiopathic changes occurred independent from specific epilepsy-associated lesions, i.e., dysplasia, neoplasia, or hippocampal sclerosis, and showed no correlation with antiepileptic drug treatment or seizure semiologies. A high frequency of spongiform white matter angiopathy was identified in young patients with chronic epilepsies. The severity of basal membrane pathology and adjacent tissue reaction is compatible with compromised BBB function. Further clinicopathological investigations will be mandatory to clarify its relation to the cause or consequence of seizures in children with intractable seizures.
    Epilepsia 06/2008; 49(5):804-15. · 3.96 Impact Factor
  • Article: Long-term use of zonisamide in refractory childhood-onset epilepsy.
    Gerhard Kluger, Andrea Zsoter, Hans Holthausen
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    ABSTRACT: This open label study examined the long-term efficacy and safety of zonisamide as adjunctive therapy in mentally retarded and multiple-handicapped patients with severe childhood-onset epilepsy. The study included 24 patients (mean age 12.5 years, range 2-40 years) which had different severe epilepsy syndromes (75% focal, 12.5% generalized, 12.5% refractory status epilepticus) refractory to at least 6 (median 10) anti-epileptic drugs. All patients were followed for at least 18 months after beginning of zonisamide treatment. Mean duration of zonisamide therapy was 55 weeks (range 5-168 weeks) and mean maintenance dosage was 7.7 mg/kg/day (range: 4-16 mg/kg/day). The patients received an average of 1.9 (range 1-3) concomitant antiepileptic drugs. The initial response rate defined as a > or =50% reduction of seizure frequency after 8 weeks was 58.3% (14 of 24 patients). Four of 14 initial responders developed loss of efficacy during long-term treatment. The retention rate after 18 months was 41.7% (10 of 24 patients). One patient (4.2%) became completely seizure-free after initiation of zonisamide treatment and remained seizure-free for the entire observation period of 18 months. Overall, zonisamide was well tolerated. Side effects were observed in 46% of patients and were mild to moderate. They mostly occurred during titration and subsided in maintenance dosing. Only in two patients (8.3%) zonisamide therapy was discontinued due to side effects (loss of appetite). No serious side effects were observed. These results are similar to the findings of Japanese studies suggesting that long-term use of adjunctive zonisamide therapy may be beneficial for treating mentally retarded, multiple handicapped patients with highly refractory childhood-onset epilepsy.
    European Journal of Paediatric Neurology 02/2008; 12(1):19-23. · 2.12 Impact Factor
  • Article: Long-term use of Levetiracetam in patients with severe childhood-onset epilepsy.
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    ABSTRACT: To assess the efficacy and tolerability of Levetiracetam (LEV) in children and adolescents with refractory epilepsy with a special interest in the long-term retention rate. One hundred and twenty-nine patients (83 male, 46 female; mean age 10.6 years/range: 6 months-39 years 9 months) were included in a prospective, open-label, add-on trial of LEV for up to 3 years. All patients had severe forms of epilepsy starting before the age of 10 often accompanied by mental retardation. Primary outcome measures were changes in seizure frequency after 6 months on the medication with LEV, with initial responders (>50% seizure reduction). Further objective was the retention rate of LEV therapy after 3 years defined as percentage of patients still taking LEV. Thirty-five patients (27.1%) were initial responders of which 5 became seizure free. The average maximum LEV dosage was 39.8 mg/kg/day (range: 6-70 mg/kg/day) with no difference responders vs. no responders. The retention rate for responders after 3 years was 22.5%. The rate of side effects was 39.8% in all patients, with the most frequent side effects being fatigue (12.5%), aggressiveness (7.8%) and gastrointestinal disorders (13.3%). Our study in patients with refractory epilepsy suggests that our initial responders were very likely to be still taking LEV after 3 years. We therefore consider treatment with LEV in this special group of patients with refractory epilepsy a promising therapeutic option, because of its favourable tolerance profile, the option of fast titration and the absence of drug interactions.
    European Journal of Paediatric Neurology 12/2007; 11(6):341-5. · 2.12 Impact Factor
  • Article: Efficacy and safety of radiosurgical callosotomy: a retrospective analysis.
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    ABSTRACT: Anterior callosotomy is a surgical option for the treatment of generalized tonic or atonic seizures associated with drop attacks. Besides open surgery, a radiosurgical callosal disconnection using the gamma knife (GK) also can be performed, but reliable data about tolerability and efficacy are sparse. Eight patients (three female, five male age range, 5 to 69 years) with severe generalized epilepsy associated with disabling drop attacks underwent GK callosotomy between 1993 and 2004. In six patients, the anterior third of the corpus callosum was radiosurgically disconnected. In one patient a second procedure with GK treatment of the middle third of the corpus callosum was added 17 months later. In two patients posterior GK callosotomy had followed partial hemispherotomy. Drop attacks (DAs) were completely abolished in three patients, and two patients had a marked DA seizure reduction of 60%. Two of four patients with additional generalized tonic-clonic seizures showed a reduction of 100%, and the remaining, a 50% and 60% decrease, respectively. Other seizure types responded less well to the radiosurgical treatment. In both patients with posterior GK callosotomy after hemispherotomy, partial seizures decreased. Beside transient headache in two patients, no immediate or long-term postradiosurgical side effects were observed. Palliative radiosurgical callosotomy is an efficient and safe noninvasive alternative to the open procedure with comparable results. No signs of postradiosurgical side effects were noted within an up to 12-year posttreatment period.
    Epilepsia 08/2006; 47(7):1184-91. · 3.96 Impact Factor
  • Article: Cerebellar Hypometabolism in Focal Epilepsy Is Related to Age of Onset and Drug Intoxication
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    ABSTRACT: Purpose: We wished to investigate the cerebellar depression of regional cerebral glucose metabolism (rCMRGlu) in patients with focal epilepsy.Method: In 170 consecutive patients with medically refractory, focal epilepsy the rCMRGlu was measured in cerebellum and brain.Results: rCMRGlu was markedly decreased in both cerebellar hemispheres and slightly in brain. The cerebellum to brain rCMRGlu ratio was significantly decreased in patients with seizure manifestation in infancy, but was normal due to a progressive decrease in brain rCMRGlu in later age. A subgroup of patients with focal epilepsy involving the frontal lobe had a reduced cerebellum/brain rCMRGlu ratio, whereas in patients with mesiotemporal lobe epilepsy (MTLE), the rCMRGlu was decreased to the same degree in cerebellum and brain. The difference in the cerebellum/brain rCMRGlu ratio between the two groups was accounted for by the younger age of the patients with focal epilepsy involving the frontal lobe, however. In another subgroup of patients with a documented history of critical drug intoxications, the cerebellar rCMRGlu was severely decreased, resulting in a significantly reduced cerebellum/brain rCMRGlu ratio.Conclusion: Our retrospective study suggests that the cerebellum is particularly vulnerable in infancy to ongoing epileptic activity and high dosage of antiepileptic drugs (AEDs).
    Epilepsia 08/2005; 37(12):1194 - 1199. · 3.96 Impact Factor
  • Article: Neuropathological spectrum of cortical dysplasia in children with severe focal epilepsies.
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    ABSTRACT: Cortical dysplasias comprise a variable spectrum of clinical, neuroradiological and histopathological findings. We report about a cohort of 25 pediatric patients (mean age 8.1+/-4.8 years) with severe drug-resistant early onset focal epilepsies (mean duration 2.1+/-0.4 years), mental/psychomotor retardation, and multilobar epileptogenesis. Compared to age-matched biopsy controls, microscopical inspection of neurosurgically resected specimens revealed dysplastic neurons with/without balloon cells in only 7 patients. According to Palmini's classification system, these lesions were categorized as focal cortical dysplasia (FCD) type II. All other patients presented with rather subtle but statistically significant neuroanatomical abnormalities. We identified increased numbers of ectopic neurons in white matter and cortical gliosis. However, most intriguing was our finding of a microcolumnar arrangement of cortical neurons in layer III. These microcolumns can be statistically defined as vertical lining of more than eight neurons (two times standard deviation of cell countings obtained from controls). In addition, neuronal perikarya were significantly smaller in epilepsy patients. Although histological abnormalities occurring during postnatal maturation of the brain challenge any neuropathological classification in this group of young patients, we propose that these findings are classified according to FCD type I. Our observations support a concept compatible with regional loss of high-order brain organization.
    Acta Neuropathologica 08/2005; 110(1):1-11. · 9.32 Impact Factor
  • Article: Distinct allelic variants of TSC1 and TSC2 in epilepsy-associated cortical malformations without balloon cells.
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    ABSTRACT: Epilepsy-associated malformations of cortical development (MCDs) comprise a variety of dysplastic and neoplastic lesions of yet undetermined molecular pathology. Histopathologic similarities between MCDs and dysplastic brain lesions in the autosomal inherited neurocutaneous phacomatosis tuberous sclerosis (TSC), which affects the TSC1 and/or TSC2 genes, suggest common pathogenetic mechanisms. Previous studies revealed different alterations of TSC1 and TSC2 in epilepsy-associated malformations and glio-neuronal tumors despite histopathologic similarities. In order to examine current clinico-pathologic classification systems of cortical malformations on the molecular level, we carried out a mutational analysis of TSC1 and TSC2 in a series of surgical specimens obtained from patients with FCD without Taylor type balloon cells (FCDIIa; n = 20), architectural dysplasias (FCDI; n = 15), nodular cortical heterotopias (NCH; n = 4), and heterotopic white matter neurons (WMNH; n = 19). In FCDIIa, abundant genomic polymorphisms were detected in TSC2 (intron 4) but no allelic variants observed in exon 17 of TSC1. This allelic distribution pattern is in contrast to findings in FCDI and WMNH but also to those previously reported in FCDIIb (Taylor's balloon cell type). The latter revealed increased frequencies of specific alleles only in TSC1. The determination of characteristic molecular genetic alterations in specific epilepsy-associated malformations will support a comprehensive clinico-pathologic classification system and help to identify molecular pathways with potential pathogenetic relevance. Our work is supported by DFG (SFB TR3 [AJB], DFG Bl 421/1-1 [IB]), BONFOR, and Deutsche Krebshilfe.
    Journal of Neuropathology and Experimental Neurology 08/2005; 64(7):629-37. · 4.26 Impact Factor
  • Article: A semiological classification of status epilepticus.
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    ABSTRACT: The classification of status epilepticus (SE) has been a subject of discussion for many years, yet no satisfactory agreement has been reached. Due to their complexity, status episodes often defy classification according to the current international classification scheme. The semiological seizure classification (SSC) has been in use in several epilepsy centers for more than a decade, and has proven to be a valid approach to the classification of epileptic seizures. Based on the detailed analysis of more than 100 episodes of SE documented with video-EEG recordings, the authors now present a proposal for a semiological classification of status epilepticus (SCSE). The SCSE reflects the assumption implied by all modern definitions of SE that "there are as many types of status as there are types of seizures" and relies on the same principles as the SSC, focusing on the main clinical manifestations and the evolution of the status episode. The clinical manifestations of SE are subdivided into semiological components and classified along three axes: the type of brain function predominantly compromised by the seizure activity, the body part involved, and the evolution over time. Each axis contains several subcategories, so that many different levels of accuracy are possible. The SCSE, just like the SSC, is meant to be part of a comprehensive epilepsy classification which classifies as independent variables (epileptogenic zone, ictal semiology, etiology, related medical conditions) the main features of the patient's epilepsy, allowing for each variable maximum flexibility.
    Epileptic disorders: international epilepsy journal with videotape 04/2005; 7(1):5-12. · 1.50 Impact Factor
  • Article: Reorganization in congenital hemiparesis acquired at different gestational ages.
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    ABSTRACT: It is well established that the reorganizational potential of the developing human brain is superior to that of the adult brain, but whether age-dependent differences exist already in the prenatal and perinatal period is not known. We have studied sensorimotor reorganization in 34 patients with congenital hemiparesis (age range, 5-27 years), using transcranial magnetic stimulation and functional magnetic resonance imaging during simple hand movements. Underlying pathologies were brain malformations (first and second trimester lesions; n = 10), periventricular brain lesions (early third trimester lesions; n = 12), and middle cerebral artery infarctions (late third trimester lesions; n = 12). Of this cohort, eight patients with malformations and all patients with periventricular lesions have been published previously. In all three groups of pathologies, transcranial magnetic stimulation identified patients in whom the paretic hand was controlled via ipsilateral corticospinal projections from the contralesional hemisphere (n = 16). In these patients, the motor dysfunction of the paretic hand correlated significantly with the timing period of the underlying brain lesion. This demonstrates that the efficacy of reorganization with ipsilateral corticospinal tracts indeed decreases during pregnancy.
    Annals of Neurology 01/2005; 56(6):854-63. · 11.09 Impact Factor
  • Article: Searching for motor functions in dysgenic cortex: a clinical transcranial magnetic stimulation and functional magnetic resonance imaging study.
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    ABSTRACT: Cortical motor organization/reorganization was studied in patients with malformation of cortical development (MCD) by applying two noninvasive motor mapping techniques: transcranial magnetic stimulation (TMS) and functional magnetic resonance (fMR) imaging. Eight patients (age range 6-22 years), all suffering from congenital hemiparesis of similar severity, were included. Underlying lesions were schizencephalies in four cases, nonschizencephalic polymicrogyria in one, and complex hemispheric malformations in three. All MCDs involved rolandic cortex of the hemisphere contralateral to the hemiparesis. Transcranial magnetic stimulation was used to search, in both hemispheres, for brain regions with corticospinal projections to the paretic hand, and cortical activation during simple repetitive movements of the paretic hand was monitored using fMR imaging. Transcranial magnetic stimulation identified abnormal ipsilateral corticospinal projections from the contralesional hemisphere to the paretic hand in six of eight patients, in all of whom fMR imaging activation of the contralesional hand area was demonstrated during paretic hand movement. In two patients with schizencephaly in this subgroup, additional activation was shown in the affected hemisphere, located in dysgenic cortex lining the schizencephalic clefts but without TMS evidence for corticospinal projections originating from these sites. Corticospinal projections to the paretic hand originating in the MCD were identified in the remaining two patients, one with (nonschizencephalic) polymicrogyria and one with a complex hemispheric malformation. Malformations of cortical development can show various degrees of participation in motor functions, ranging from corticospinal ("primary") motor control, to putative participation as "nonprimary" motor areas, to absence of evidence for any functional participation. This information can be obtained, noninvasively, using a combination of TMS and fMR imaging.
    Journal of Neurosurgery 09/2004; 101(1 Suppl):69-77. · 2.96 Impact Factor
  • Article: Systematic Testing of Medical Intractability for Carbamazepine, Phenytoin, and Phenobarbital or Primidone in Monotherapy for Patients Considered for Epilepsy Surgery
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    ABSTRACT: Purpose: To assess medical intractability in patients considered for restrictive epilepsy surgery.Methods: Seventy-four patients received single drug treatment with carbamazepine (CBZ), phenytoin (PHT), and either phenobarbital (PB) or primidone (PRM). Medical intractability was established if seizure control was not obtained despite maximum tolerable doses of the drug. In all, 120 single drug treatments were administered with the drugs that has not been administered at maximal doses in monotherapy before the study.Results: Complete seizure control was not achieved in any patient. However, 7 patients (9.5%) had significant seizure reduction of at least 80%. In 4 patients, only the third antiepileptic drug (AED) proved effective.Conclusion: The poor result of AED monotherapy in our patients may be attributed to the patients’long-standing chronic epilepsies and high seizure frequencies. Our findings suggest that despite the failure of one or two major AEDs in controlling seizures completely, further single drug treatment may still improve the quality of life in some patients who are candidates for epilepsy surgery.
    Epilepsia 06/1996; 37(7):675 - 679. · 3.96 Impact Factor

Institutions

  • 2010–2011
    • Universitätsklinikum Erlangen
      Erlangen, Bavaria, Germany
  • 2005–2010
    • Eberhard-Karls-Universität Tübingen
      • Department of Neuropaediatrics, Developmental Neurology, Social Paediatrics
      Tübingen, Baden-Wuerttemberg, Germany
  • 2008
    • Friedrich-Alexander Universität Erlangen-Nürnberg
      Erlangen, Bavaria, Germany
    • University Hospital Motol
      Praha, Hlavni mesto Praha, Czech Republic
    • Schön Klinik Vogtareuth
      Vogtareuth, Bavaria, Germany