H Lüders

Kyushu University, Hukuoka, Fukuoka, Japan

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Publications (258)1085.44 Total impact

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    ABSTRACT: Electrical brain stimulation is used in a variety of clinical situations, including cortical mapping for epilepsy surgery, cortical stimulation therapy to terminate seizure activity in the cortex, and in deep brain stimulation therapy. However, the effects of stimulus parameters are not fully understood. In this study, we systematically tested the impact of various stimulation parameters on the generation of motor symptoms and afterdischarges (ADs). Focal electrical stimulation was delivered at subdural cortical, intracortical, and hippocampal sites in a rat model. The effects of stimulus parameter on the generation of motor symptoms and on the occurrence of ADs were examined. The effect of stimulus irregularity was tested using random or regular 50Hz stimulation through subdural electrodes. Hippocampal stimulation produced ADs at lower thresholds than neocortical stimulation. Hippocampal stimulation also produced significantly longer ADs. Both in hippocampal and cortical stimulation, when the total current was kept constant with changing pulse width, the threshold for motor symptom or AD was lowest between 50 and 100Hz and higher at both low and high frequencies. However, if the pulse width was fixed, the threshold did not increase above 100Hz and it apparently continued to decrease through 800Hz even if the difference did not reach statistical significance. There was no significant difference between random and regular stimulation. Overall, these results indicate that electrode location and several stimulus parameters including frequency, pulse width, and total electricity are important in electrical stimulation to produce motor symptoms and ADs.
    Epilepsy research 11/2012; · 2.48 Impact Factor
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    ABSTRACT: Diffusion tensor imaging (DTI) provides information about magnitude (diffusivity) and directionality (fractional anisotropy, FA) of water diffusion and allows visualization of major white matter tracts. The arcuate fasciculus (AF) connects anterior (Broca's) and posterior (Wernicke's) language areas. We hypothesized that essential language areas identified by direct cortical stimulation would colocalize with areas revealing subcortical connectivity via the AF. Fourteen patients with pharmacoresistant left hemispheric epilepsy and left hemisphere language dominance underwent invasive evaluations for localization of epileptogenicity and functional mapping. DTI and T1-weighted volumetric magnetic resonance imaging (MRI) scans were coregistered, and subdural grid electrodes identified on postimplantation computed tomography (CT) scans were also coregistered to the MRI scans. The AF was reconstructed from a region lateral to the corona radiata on the FA map. Colocalization, defined as <1 cm between the AF and the electrode positions delineating language cortex, was visually assessed with excellent reliability (Cronbach's alpha = 0.98). A total of 71 subdural grid contacts were overlying language cortex. Nineteen contacts in eight patients were over Broca's area, 16 of which (84.2%) colocalized with the AF. Fifty-two contacts in 10 patients were over Wernicke's area, with colocalization in 29 patients (55.8%). Colocalization was significantly greater in anterior regions than in posterior regions [chi(2)(1) = 4.850, p < 0.05]. The AF, as visualized with DTI, colocalized well with anterior language areas, but less so with posterior language areas, inferring that the latter are more spatially dispersed.
    Epilepsia 12/2009; 51(4):639-46. · 3.96 Impact Factor
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    ABSTRACT: Describe an ictal EEG pattern of paradoxical lateralization in children with unilateral encephaloclastic hemispheric lesion acquired early in life. Of 68 children who underwent hemispherectomy during 2003-2005, scalp video-EEG and brain MRI of six children with an ictal scalp EEG pattern discordant to the clinical and imaging data were reanalyzed. Medical charts were reviewed for clinical findings and seizure outcome. Age of seizure onset was 1 day-4 years. The destructive MRI lesion was an ischemic stroke in 2, a post-infectious encephalomalacia in 2, and a perinatal trauma and hemiconvulsive-hemiplegic syndrome in one patient each. Ictal EEG pattern was characterized by prominent ictal rhythms with either 3-7 Hz spike and wave complexes or beta frequency sharp waves (paroxysmal fast) over the unaffected (contralesional) hemisphere. Scalp video-EEG was discordant, however, other findings of motor deficits (hemiparesis; five severe, one mild), seizure semiology (4/6), interictal EEG abnormalities (3/6), and unilateral burden of MRI lesion guided the decision for hemispherectomy. After 12-39 months of post-surgery follow up, five of six patients were seizure free and one has brief staring spells. We describe a paradoxical lateralization of the EEG to the "good" hemisphere in children with unihemispheric encephaloclastic lesions. This EEG pattern is compatible with seizure free outcome after surgery, provided other clinical findings and tests are concordant with origin from the abnormal hemisphere.
    Epileptic disorders: international epilepsy journal with videotape 10/2009; 11(3):215-21. · 1.17 Impact Factor
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    ABSTRACT: Electrophysiological studies in primates indicate that the eye fields of the cerebral hemispheres control gaze in three-dimensional space, and contain neurons that encode both conjugate (versive) and vergence eye movements. Two patients with epilepsy who exhibited disconjugate contraversive horizontal eye movements are described, one during electrical stimulation of the frontal eye fields and the other during focal seizures. We postulate that these eye movements resulted from combined contralateral version and vergence, and suggest that human cortical eye fields also govern visual search in a three-dimensional world, shifting the point of fixation between targets lying in different directions and at different depths.
    Journal of neurology, neurosurgery, and psychiatry 07/2009; 80(6):683-5. · 4.87 Impact Factor
  • Neuroscience Research - NEUROSCI RES. 01/2009; 65.
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    ABSTRACT: Dejerine and Benson and Geschwind postulated disconnection of the dominant angular gyrus from both visual association cortices as the basis for pure alexia, emphasizing disruption of white matter tracts in the dominant temporooccipital region. Recently functional imaging studies provide evidence for direct participation of basal temporal and occipital cortices in the cognitive process of reading. The exact location and function of these areas remain a matter of debate. To confirm the participation of the basal temporal region in reading. Extraoperative electrical stimulation of the dominant hemisphere was performed in three subjects using subdural electrodes, as part of presurgical evaluation for refractory epilepsy. Pure alexia was reproduced during cortical stimulation of the dominant posterior fusiform and inferior temporal gyri in all three patients. Stimulation resulted in selective reading difficulty with intact auditory comprehension and writing. Reading difficulty involved sentences and words with intact letter by letter reading. Picture naming difficulties were also noted at some electrodes. This region is located posterior to and contiguous with the basal temporal language area (BTLA) where stimulation resulted in global language dysfunction in visual and auditory realms. The location corresponded with the visual word form area described on functional MRI. These observations support the existence of a visual language area in the dominant fusiform and occipitotemporal gyri, contiguous with basal temporal language area. A portion of visual language area was exclusively involved in lexical processing while the other part of this region processed both lexical and nonlexical symbols.
    Neurology 12/2008; 71(20):1621-7. · 8.25 Impact Factor
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    Tim Wehner, Hans Lüders
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    ABSTRACT: A significant minority of patients with focal epilepsy are candidates for resective epilepsy surgery. Structural and functional neuroimaging plays an important role in the presurgical evaluation of theses patients. The most frequent etiologies of pharmacoresistant epilepsy in the adult population are mesial temporal sclerosis, malformations of cortical development, cavernous angiomas, and low-grade neoplasms. High-resolution multiplanar magnetic resonance imaging (MRI) with sequences providing T1 and T2 contrast is the initial imaging study of choice to detect these epileptogenic lesions. The epilepsy MRI protocol can be individually tailored when considering the patient's clinical and electrophysiological data. Metabolic imaging techniques such as positron emission tomography (PET) and single photon emission tomography (SPECT) visualize metabolic alterations of the brain in the ictal and interictal states. These techniques may have localizing value in patients with a normal MRI scan. Functional MRI is helpful in non-invasively identifying areas of eloquent cortex.Developments in imaging technology and digital postprocessing may increase the yield for imaging studies to detect the epileptogenic lesion and to characterize its connectivity within the epileptic brain.
    Journal of Clinical Neurology 04/2008; 4(1):1-16. · 1.89 Impact Factor
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    ABSTRACT: Subdural electrodes play a very important role in the evaluation of a percentage of patients being considered for epilepsy surgery. Electrical activity at very low and very high frequencies, beyond the practical range of scalp EEG, can be recorded subdurally and may contain considerable information not available non-invasively. The recording and stimulating procedures for using chronically implanted subdural electrodes to localize the epileptogenic zone and map eloquent functions of the human cortex are well established, and complication rates are low. Complications include infections, CSF leak, and focal neurologic deficits, all of which tend to be increased with a higher number of electrodes and longer duration of recordings. Careful consideration of the risks and benefits should be coupled with a firm hypothesis about the epileptogenic zone derived from the non-invasive components of the epilepsy workup to guide the decision about whether and where to implant subdural electrodes. When they are employed to answer a specific question in an individual patient, subdural electrodes can optimize the clinical outcome of a candidate for epilepsy surgery.
    Clinical Neurophysiology 02/2008; 119(1):11-28. · 3.14 Impact Factor
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    ABSTRACT: In evaluation of patients with complex partial seizures who are candidates for surgical treatment, exact definition of the epileptogenic focus is essential for a good surgical outcome. We report a new technique which permits detailed mapping of the epileptogenic activity in the basal temporal lobe and the convexity of the temporal lobe. The technique consists of placement of at least 16 basal temporal electrodes and an additional 64 electrodes covering the temporal convexity. This extensive coverage permits accurate definition of the limits of the epileptogenic focus and also of adjacent functional areas and therefore allows more significant determination than have previous techniques of the ideal extent of the surgical resection. This accuracy cannot be achieved with depth electrodes or the limited coverage provided by previously reported epidural or subdural electrode techniques.RÉSUMÉDans le bilan de patients présentant des crises partielles complexes et qui sont candidats à un traitement chirurgical, une définition exact du foyer épileptogène est essentielle dans la perspective d'un bon résultat post-opératoire. Les auteurs rappor-tent une nouvelle technique qui permet d'établir une topographie détaillée de l'activité paroxystique dans la région basale et la convexité du lobe temporal. Cette technique consiste à placer un minimum de 16 électrodes temporales basales et 64 électrodes supplémentaires sur la convexité temporale. Cette large couverture permet de défiinir précisément les limites du foyer ṕileptogene et des régions fonctionnelles adjacentes; elle permet done de déterminer avec une précision supérieure à celle des techniques antérieures l'extension idéale de la résection chirurgicale. Cette précision ne peut être obtenue par des électrodes pro-fondes ou par la couverture limitée fournie par les techniques antérieurement décrites utilisant des électrodes épi- ou sous-durales.RESUMENEn la evaluación de enfermos con ataques parciales comple-jos, considerados como candidates para tratamiento quirúrgico, resulta esencial la definicióm del foco epileptogénico para consequir unos resultados quirúrgicos de buena calidad. Se presenta una técnica nueva que permite conseguir un mapa detallado de la actividad epileptogénica en la región basal y en la convexidad del lóbulo temporal. Esta técnica consiste en la colocación de, al menos, 16 electrodos basales temporales y de 64 electrodos que cubren la convexidad del lóbulo temporal. Esta ámplia cobertura permite una válida definición de los límites de los focos epilep-togénicos y también de las áreas funcionales adyacentes que, por lo tan to, permite determinar con precisión, más fiable que con técnicas previas, la amplitud ideal de la resección quirúrgica. Esta exactitud no puede consequirse con electrodos profundos ni con el emplazamiento de electrodos epi o subdurales como ha sido previamente publicado.ZUSAMMENFASSUNGBei der Untersuchung der Patienten mit komplexen Partialan-fllen, die möglicherweise für eine chirurgische Behandlung in Frage kommen, ist eine genaue Abgrenzung des epileptogenen Fokus' unabdingbar für einen guten Operationserfolg. Wir be-richten über eine neue Technik, welche ein detailliertes Mapping der epileptogenen Aktivitt über der Basis und der Konvexitt des Temporallappens erlaubt. Die Technik umfaβt die Plazierung von wenigstens 16 basalen Elektroden und Weiteren 64 Konvex-ittselektroden. Diese dichte Besetzung erlaubt die akkurate Abgrenzung der Fokusregion sowie angrenzender funktioneller Ge-biete. Damit lβt sich mit signifikant besserer Zuverlssigkeit das Ausmaβ der vorgesehenen Resektion fest bestimmen. Die Genauigkeit kann weder mit Tiefenelektroden noch mit be-grenzten Ableitungen–wie kürzhch berichtet–durch epi- oder subdurale Elektroden-Technik erreicht werden.
    Epilepsia 11/2007; 30(2):131 - 142. · 3.96 Impact Factor
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    ABSTRACT: The extent of resection was assessed in 45 temporal lobectomies for medically intractable epilepsy with mapped temporal lobe foci. Postoperative magnetic resonance imaging (MRI) in the coronal plane was used to quantify the extent of resection of superior lateral, inferior lateral, basal, and medial structures, including the amygdalohippocampal complex. A new 20-compartment model of the temporal lobe was used for this assessment. Blinded interobserver variability was minimal. Intraoperative measurements and maps routinely overestimated the actual extent of resection, especially of medial structures. One year after surgery, 70% of patients remained seizure-free (except for auras). Seizure-free outcome was accomplished despite varying degrees of resection, but was more likely achieved with more extensive resections in all compartments. Among patients with mesiobasal foci, seizure-free outcome correlated significantly with extent of resection of amygdalohippocampal complex. We conclude that assessment of extent of resection by postoperative MRI provides an objective basis of evaluating outcome after temporal lobectomy. It allows a rational approach to understanding of operative failures and is potentially useful in comparing efficacy of various surgical approaches.RÉSUMÉL'étendue de la résection a étéévaluée chez 45 patients ayant subi une lobectomie temporale pour épilepsie rebelle au traitement médical, dans laquelle une carte des foyers temporaux avaient étéétablie. La RMN post-opératoire en plan coronal a été; utilisée pour quantifier extension de la résection au niveau des structures supérieure, latérale, infdrieure laterale, basale et médiane incluant le complexe amygdalo-hippocampique. Un nouveau modèle à 20 compartiments du lobe temporal a été utilisé pour cette étude. La variabilité interobservateur en aveugle a étéétudiée, les résultats ont montré qu'elle était minime. Les mesures intraopératoires et les cartographies ont trés habituelle-ment surestimé extension réelle de la résection, en particulier au niveau des structures médianes. Une année après la chirurgie, 70% des patients restaient libres de toute crise (en dehors des auras). Une évolution sans crise a été obtenue malgré diftérents degrés de résection, elle était cependant plus probable lors de résection plus étendue dans tous les compartiments. Parmi les patients présentant des foyers mésio-basio, évolution sans crise a été corrélée significativement avec étendue de la résection du complexe amygdalohippocampique. Les auteurs concluent que évaluation de extension une résection par la RMN post-opératoire procure une base objective évaluation pour Involution post-chirurgicale. Il s'agit une approche rationnelle en vue une comprehension des mauvais résultats opératoires, et cette approche peut être utile pour comparer efficacité de diverses attitudes chirurgicales.ZUSAMMENFASSUNGDas Ausmaß der Resektion wurde bei 45 temporalen Lobektomien ausgewertet, die bei therapeiresistenten Epilepsien mit einem Temporallappenfokus (Mapping) durchgeführt wurden. Postoperative MR's in coronarer Einstellung wurden benutzt, um das Ausmaß der Resektion im superior-lataralen, inferiorlateralen, basalen und medialen Anteil einschließlich dem amygdalo-hippocampalen Bereich zu quantifizieren. Ein neues 20-Compartment-Modell des Temporallappens wurde für diese Auswertung benutzt. Die Interobserver-Variabilitt wurde blind untersucht und als minimal gefunden. Intraoperative Messungen und EEG-Maps überschtzen regelmßig das aktuelle Ausmaß der Resektion speziell der medialen Strukturen. Ein Jahr nach der Operation waren 70% der Patienten anfallsfrei (bis auf Auren). Die Anfallsfreiheit wurde ungeachtet des unterschiedlichen Ausmaßes der Resektion erzielt, aber sie war bei einer extensiven Resektion in alien Anteilen wahrscheinlicher. Bei Patienten mit mesio- basalen Foci korrelierte das Ergebnis “anfallsfrei” significant mit dem Ausmaß der Resektion des amygdalo-hippocampalen Komplexes. Es wird geschlossen, daß die Auswertung des Außmaßes von Resektionen mit Hilfe eines postoperativen MR's eine objektive Grundlage liefert, um das Ergebnis nach temporaler Lobektomie zu bewerten. Es ermöglicht einen rationalen Zugang zum Verstndnis von operativen Mißerfolgen und ist möglicherweise nützlich beim Vergleich ver-schiedener chirurgischer Vorgehensweisen.
    Epilepsia 11/2007; 30(6):756 - 762. · 3.96 Impact Factor
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    ABSTRACT: We present correlations of extent of temporal lobectomy for intractable epilepsy with postoperative memory changes (20 cases) and abnormalities of visual field and neurologic examination (45 cases). Postoperative magnetic resonance imaging (MRI) in the coronal plane was used to quantify anteroposterior extent of resection of various quadrants of the temporal lobe, using a 20-compartment model of that structure. The Wechsler Memory Scale-Revised (WMS-R) was administered pre-operatively and postoperatively. Postoperative decrease in percentage of retention of verbal material correlated with extent of medial resection of left temporal lobe, whereas decrease in percentage of retention of visual material correlated with extent of medial resection of right temporal lobe. These correlations approached but did not reach statistical significance. Extent of resection correlated significantly with the presence of visual field defect on perimetry testing but not with severity, denseness, or congruity of the defect. There was no correlation between postoperative dysphasia and extent of resection in any quadrant. Assessment of extent of resection after temporal lobectomy allows a rational interpretation of postoperative neurologic deficits in light of functional anatomy of the temporal lobe.RÉSUMÉLes auteurs présentent les corrélations entre extension une lobectomie temporale pour épilepsie rebelle et des troubles mnésiques post-opératoires (20 cas) et des anomalies du champ visuel et de examen neurologique (45 cas). Une RMN post-opératoire en plan coronal a été utilisée pour quantifier extension antéro-postérieure de la résection de divers quadrants du lobe temporal, au moyen un modèle à vingt compartiments de cette structure. échelle de mémoire de Wechsler révisée (VMS-R) a été administrée avant et après intervention. Une diminution post-opératoire du pourcentage de rétention du matériel verbal a été corrélée avec extension de la résection médiane du lobe temporal gauche, alors qu'une diminution du pourcentage de rétention de matériel visuel a été corrélée avec extension de la résection médiane du lobe temporal droit. Ces corrélations n'atteignaient pas tout à fait le seuil de signification statistique. étendue de la résection a été corrélée de façon significative avec la présence un déficit du champ visuel à examen campimétrique, mais non avec la sévérité la densité ou lacongruance de ce déficit. Il n'y avait pas de corrélation entre une dysphasie post-opératoire et étendue de la résection en quelque quadran que ce soit. évaluation de étendue de la résection après lobectomie temporale permet interpréter de façon rationnelle les déficits neurologiques post-opératoires, à la lumière de la neuro-anatomie fonctionnelle du lobe temporal.RESUMENPresentamos las correlaciones de una lobectomía temporal amplia como tratamiento de la epilepsía incontrolable con los trastornos de la memoria postoperatorios (20 casos), anormal-idades de los campos visuales y de la exploración neurológica (45 casos). Una RM postoperatoria en el piano coronal se utilizó para cuantificar la extensión anteroposterior de la resección de varios cuadrantes del lóbulo temporal usando un modelo de 20 compartimentos de esta estructura. La escala de memoria re-visada de Wechsler (WMS-R) se aplicó preoperatoria y postoperatoriamente. La reducción postoperatoria del porcentaje de retención de material verbal correlacionó bien con la extensión de la resección medial del lóbulo temporal izquierdo mientras que la reducción del porcentaje del material de retención visual correlacionó con la extensión de la resección medial del lóbulo temporal derecho. Estas correlaciones se acercaron pero no alcanzaron significado estadistico. La extensión de la reseccion correlacionó significativamente con la presencia de defectos del campo visual en la perimetría pero no con la severidad, densidad o congruencia de estos defectos. No se observó correlatión entre la disfasia postoperatoria y la extensión de la resección de ningún cuadrante. La determinatión de la extensión de la resección después de la lobectomia temporal permite una interpretatión racional de los deficits neurológicos postoperatonos de acuerdo con la anatomía funcional del lóbulo temporal.ZUSAMMENFASSUNGEs werden Korrelationen zwischen dem Ausmaß der temporalen Lobektomie bei therapeirefraktärer Epilepsie mit Gedächtnisänderungen (20 Fälle) und Abnormalitäten des Gesichtsfeld und des neurologischen Status (45 Fälle) gezeigt. Postoperative MR-Coronarschnitte wurden zur Quantifizierung des anterior-posterioren Ausmaßes der Resektion verschiedener Temporallappen- Quadranten unter Zuhilfenahme eines 20-Compartment-Modells dieser Struktur benutzt. Prae- und postoperativ wurde die überarbeitete Wechseler-Gedächtnis-Skala benutzt. Die postoperative Abnahme im verbalen Gedächtnis korrelierte mit dem Ausmaß der medialen Resektion des li. Temporeallappens, die Abnahme des visuellen Gedächtnisses mit dem Ausmaß einer medialen Resektion des rechten Temporallappens. Diese Korrelationen kamen in die Nähe einer statistischen Signiflkanz. Das Ausmaß der Resektion korrelierte signifikant mit dem Auftreten von Gesichtsfelddefekten in der Perimetric jedoch nicht mit der Schwere, der Dichte oder Deckungsgleichheit des Defektes. Es gab keine Korrelation zwischen einer postoperativen Dysphasie und dem Resektionsausmaßjedes Quandranten. Die Auswertung des Resektionsaumaßes nach temporaler Lobektomie erlaubt eine rationale Interpretation von postoperativen neurologischen Defiziten in Bezug auf die funktionelle Anatomie des Temporallappens.
    Epilepsia 11/2007; 30(6):763 - 771. · 3.96 Impact Factor
  • Clinical Neurophysiology. 10/2007; 118(10):e204.
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    ABSTRACT: Frontal lobe epilepsy (FLE) surgery is the second most common surgery performed to treat pharmacoresistant epilepsy. Yet, little is known about long-term seizure outcome following frontal lobectomy. The aim of this study is to investigate the trends in longitudinal outcome and identify potential prognostic indicators in a cohort of FLE patients investigated using modern diagnostic techniques. We reviewed 70 patients who underwent a frontal lobectomy between 1995 and 2003 (mean follow-up 4.1 +/- 3 years). Data were analysed using survival analysis and multivariate regression with Cox proportional hazard models. A favourable outcome was defined as complete seizure-freedom, allowing for auras and seizures restricted to the first post-operative week. The estimated probability of complete seizure-freedom was 55.7% [95% confidence interval (CI) = 50-62] at 1 post-operative year, 45.1% (95% CI = 39-51) at 3 years, and 30.1% (95% CI = 21-39) at 5 years. Eighty per cent of seizure recurrences occurred within the first 6 post-operative months. Late remissions and relapses occurred, but were rare. After multivariate analysis, the following variables retained their significance as independent predictors of seizure recurrence: MRI-negative malformation of cortical development as disease aetiology [risk ratio (RR) = 2.22, 95% CI = 1.40-3.47], any extrafrontal MRI abnormality (RR = 1.75, 95% CI = 1.12-2.69), generalized/non-localized ictal EEG patterns (RR = 1.83, 95% CI = 1.15-2.87), occurrence of acute post-operative seizures (RR = 2.17, 95% CI = 1.50-3.14) and incomplete surgical resection (RR = 2.56, 95% CI = 1.66-4.05) (log likelihood-ratio test P-value < 0.0001). More than half of patients in favourable prognostic categories were seizure-free at 3 years, and up to 40% were seizure-free at 5 years, compared to <15% in those with unfavourable outcome predictors. These data underscore the importance of appropriate selection of potential surgical candidates.
    Brain 03/2007; 130(Pt 2):574-84. · 9.92 Impact Factor
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    ABSTRACT: We present correlations of extent of temporal lobectomy for intractable epilepsy with postoperative memory changes (20 cases) and abnormalities of visual field and neurologic examination (45 cases). Postoperative magnetic resonance imaging (MRI) in the coronal plane was used to quantify anteroposterior extent of resection of various quadrants of the temporal lobe, using a 20-compartment model of that structure. The Wechsler Memory Scale-Revised (WMS-R) was administered preoperatively and postoperatively. Postoperative decrease in percentage of retention of verbal material correlated with extent of medial resection of left temporal lobe, whereas decrease in percentage of retention of visual material correlated with extent of medial resection of right temporal lobe. These correlations approached but did not reach statistical significance. Extent of resection correlated significantly with the presence of visual field defect on perimetry testing but not with severity, denseness, or congruity of the defect. There was no correlation between postoperative dysphasia and extent of resection in any quadrant. Assessment of extent of resection after temporal lobectomy allows a rational interpretation of postoperative neurologic deficits in light of functional anatomy of the temporal lobe.
    Epilepsia 01/2007; 30(6):763-71. · 3.91 Impact Factor
  • Clinical Neurophysiology - CLIN NEUROPHYSIOL. 01/2007; 118(9).
  • Dileep R Nair, Hans Lüders
    Nature Clinical Practice Neurology 12/2006; 2(11):594-5. · 7.64 Impact Factor
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    ABSTRACT: The recent proposal by the ILAE Task Force for Epilepsy Classification is a multiaxial, syndrome-oriented approach. Epilepsy syndromes--at least as defined by the ILAE Task Force--group patients according to multiple, usually poorly defined parameters. As a result, these syndromes frequently show significant overlap and may change with patient age. We propose a five-dimensional and patient-oriented approach to epilepsy classification. This approach shifts away from syndrome orientation, using independent criteria in each of the five dimensions similarly to the diagnostic process in general neurology. The main dimensions of this new classification consist of (1) localizing the epileptogenic zone, (2) semiology of the seizure, (3) etiology, (4) seizure frequency, and (5) related medical conditions. These dimensions characterize all information necessary for patient management, are independent parameters, and include information more pertinent than the ILAE axes with regard to patient management. All cases can be classified according to this five-dimensional system, even at initial encounter when no detailed test results are available. Information from clinical tests such as MRI and EEG are translated into the best possible working hypothesis at the time of classification, allowing increased precision of the classification as additional information becomes available.
    Der Nervenarzt 09/2006; 77(8):961-9. · 0.80 Impact Factor
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    ABSTRACT: Pharmacoresistant epilepsy arising from the dominant temporal region in patients with intact memory and normal anatomical imaging, presents major challenges in the preoperative definition of the epileptogenic zone, and the planning of the extent of the surgical resection. We report on the case of a 42-year-old, right-handed male who presented with recurrent daily seizures that were resistant to antiepileptic drugs. Multiple, non-invasive (scalp) video-EEG evaluations revealed focal epilepsy arising from the left fronto-temporal region. Multiple high resolution MRIs that were performed at multiple Epilepsy Centers failed to show any abnormality. Fluoro-deoxyglucose PET scan showed extensive, left antero-mesial temporal hypometabolism, and ictal SPECT showed increased perfusion in the left insula in addition to the left mesial and anterior temporal pole. Neuropsychological testing and intracarotid methohexital testing revealed excellent memory to the left, dominant side. A two-stage invasive evaluation with subdural grid electrodes followed by depth electrode recordings allowed the localization of the epileptogenic region to the temporal pole. A selective resection of the left temporal pole (that spared the hippocampal formation) resulted in a seizure-free outcome (one year follow-up) with no significant consequences on memory function. We conclude that targeted, invasive recording techniques should be used for the accurate localization and delineation of the extent of the epileptogenic zone in cases of suspected, non-lesional, dominant hemisphere, temporal lobe epilepsy with preserved memory function. The use of the staged invasive approach may increase the chances for memory (function) sparing through tailored, temporal resection.
    Epileptic disorders: international epilepsy journal with videotape 08/2006; 8 Suppl 2:S27-35. · 1.17 Impact Factor
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    ABSTRACT: Der krzlich erschienene Vorschlag der ILAE-Taskforce zur Epilepsieklassifikation ist ein multiaxialer, syndromorientierter Ansatz. Hierbei werden die Patienten unterschiedlichen und oftmals unzureichend definierten Kriterien zugeordnet. Die resultierenden Syndrome haben hufig keine tiologische oder pathophysiologische Relevanz, berlappen und wechseln je nach Alter des Patienten. Wir schlagen einen 5-dimensionalen, patientenorientierten Ansatz zur Klassifikation der Epilepsien vor. Dieser Ansatz wendet sich von der Orientierung an Syndromen ab und basiert stattdessen auf dem methodologischen Ansatz der allgemeinen Neurologie, in dem einerseits das klinische Bild des einzelnen Patienten im Mittelpunkt steht und andererseits in jeder Dimension voneinander unabhngige und mglichst operationalisierbare Kriterien angewandt und schlielich zusammengefhrt werden. Die Dimension dieser Klassifikation sind: (1) Lokalisation der epileptogenen Zone, (2) Semiologie der epileptischen Anflle, (3) tiologie, (4) Anfallshufigkeit und (5) sonstige relevante medizinische Faktoren. Diese Dimensionen enthalten alle fr das Management eines Patienten notwendige Information und sind voneinander unabhngige Parameter. Alle Patienten knnen selbst beim initialen Patientenkontakt sinnvoll in das System eingeordnet werden, auch wenn noch keine apparativen Untersuchungen durchgefhrt wurden. Die Information aller Untersuchungen (z. B. MRT, EEG) fliet zum jeweiligen Zeitpunkt der Klassifikation in die Zuordnung des Patienten ein und erlaubt mit jeder neu verfgbaren Information eine Zunahme der Przision und Validitt der Klassifikation.The recent proposal by the ILAE Task Force for Epilepsy Classification is a multiaxial, syndrome-oriented approach. Epilepsy syndromes – at least as defined by the ILAE Task Force – group patients according to multiple, usually poorly defined parameters. As a result, these syndromes frequently show significant overlap and may change with patient age. We propose a five-dimensional and patient-oriented approach to epilepsy classification. This approach shifts away from syndrome orientation, using independent criteria in each of the five dimensions similarly to the diagnostic process in general neurology. The main dimensions of this new classification consist of (1) localizing the epileptogenic zone, (2) semiology of the seizure, (3) etiology, (4) seizure frequency, and (5) related medical conditions. These dimensions characterize all information necessary for patient management, are independent parameters, and include information more pertinent than the ILAE axes with regard to patient management. All cases can be classified according to this five-dimensional system, even at initial encounter when no detailed test results are available. Information from clinical tests such as MRI and EEG are translated into the best possible working hypothesis at the time of classification, allowing increased precision of the classification as additional information becomes available.
    Der Nervenarzt 07/2006; 77(8):961-969. · 0.80 Impact Factor
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    ABSTRACT: To assess short- and long-term seizure freedom, the authors reviewed 371 patients who underwent anterior temporal lobectomy to treat pharmacoresistant epilepsy. The mean follow-up duration was 5.5 years (range 1 to 14.1 years). Fifty-three percent of patients were seizure free at 10 years. The authors identified multiple predictors of recurrence. Results of EEG performed 6 months postoperatively correlated with occurrence and severity of seizure recurrence, in addition to breakthrough seizures with discontinuation of antiepileptic drugs.
    Neurology 07/2006; 66(12):1938-40. · 8.25 Impact Factor

Publication Stats

8k Citations
1,085.44 Total Impact Points

Institutions

  • 2012
    • Kyushu University
      Hukuoka, Fukuoka, Japan
  • 2008–2012
    • Case Western Reserve University School of Medicine
      • Department of Neurology
      Cleveland, Ohio, United States
    • Barrow Neurological Institute
      Phoenix, Arizona, United States
  • 2009
    • Universidade Federal de São Paulo
      San Paulo, São Paulo, Brazil
    • The Bracton Centre, Oxleas NHS Trust
      Дартфорде, England, United Kingdom
    • Cleveland State University
      Cleveland, Ohio, United States
  • 1982–2007
    • Cleveland Clinic
      • • Neurological Institute
      • • Center for Epilepsy
      • • Department of Neuroradiology
      Cleveland, OH, United States
  • 2003–2006
    • University of Münster
      • Department of Neurology
      Münster, North Rhine-Westphalia, Germany
  • 2005
    • Baylor College of Medicine
      • Department of Neurology
      Houston, TX, United States
  • 2001–2002
    • Philipps University of Marburg
      • Klinik für Neurologie (Marburg)
      Marburg, Hesse, Germany
  • 2000
    • National Institutes of Health
      Maryland, United States
    • Tottori University
      • Division of Urology
      Tottori, Tottori-ken, Japan
  • 1998–2000
    • Ludwig-Maximilian-University of Munich
      • • Department of Neurology
      • • Department of Urology
      München, Bavaria, Germany
  • 1999
    • Texas Tech University Health Sciences Center
      • Department of Neurology
      Lubbock, TX, United States
  • 1996–1997
    • Heinrich-Heine-Universität Düsseldorf
      • Neurologische Klinik
      Düsseldorf, North Rhine-Westphalia, Germany
    • New York Medical College
      New York City, New York, United States
    • Singapore General Hospital
      • Department of Neurology
      Tumasik, Singapore
    • Mediterranean University of Reggio Calabria
      Reggio di Calabria, Calabria, Italy
  • 1995
    • Medical College of Wisconsin
      • Department of Neurology
      Milwaukee, WI, United States
  • 1989
    • Emory University
      Atlanta, Georgia, United States
  • 1980
    • Columbia University
      • Department of Neurology
      New York City, NY, United States