PubMed Health⌕ Search

Biomedical subjects

H Lüders

Publications and source records attributed to H Lüders.

At least 19 recordsLinked to original sources
PubMed2003

Importance of F18-fluorodeoxy-D-2-glucose positron emission tomography (FDG-PET) for staging and therapy control of Hodgkin's lymphoma in childhood and adolescence - consequences for the GPOH-HD 2003 protocol.

The prognosis for children and adolescents with Hodgkin's lymphoma is excellent. However, many patients will show secondary malignancies 15-30 years after the initial diagnosis, which appears to be connected with the intensity of treatment during primary disease. In the GPOH-HD 95 trial, the indication for radiotherapy was limited to patients who did not show a complete remission after chemotherapy, as determined radiographically. In the future protocol, the indication for radiotherapy in patients with early-stage Hodgkin's lymphoma should be further refined by using FDG-PET for evaluating the response to chemotherapy. Furthermore, in patients at an advanced stage of the disease, it should be determined if sequential FDG-PET research during chemotherapy can separate patients into subgroups with an excellent or a poor prognosis. This article gives a review of the current literature on FDG-PET in patients with Hodgkin's lymphoma and outlines the consequences for future protocols.

Adolescent↗
PubMed2001

The localizing value of ictal EEG in focal epilepsy.

OBJECTIVE: To investigate the lateralization and localization of ictal EEG in focal epilepsy. METHODS: A total of 486 ictal EEG of 72 patients with focal epilepsy arising from the mesial temporal, neocortical temporal, mesial frontal, dorsolateral frontal, parietal, and occipital regions were analyzed. RESULTS: Surface ictal EEG was adequately localized in 72% of cases, more often in temporal than extratemporal epilepsy. Localized ictal onsets were seen in 57% of seizures and were most common in mesial temporal lobe epilepsy (MTLE), lateral frontal lobe epilepsy (LFLE), and parietal lobe epilepsy, whereas lateralized onsets predominated in neocortical temporal lobe epilepsy and generalized onsets in mesial frontal lobe epilepsy (MFLE) and occipital lobe epilepsy. Approximately two-thirds of seizures were localized, 22% generalized, 4% lateralized, and 6% mislocalized/lateralized. False localization/lateralization occurred in 28% of occipital and 16% of parietal seizures. Rhythmic temporal theta at ictal onset was seen exclusively in temporal lobe seizures, whereas localized repetitive epileptiform activity was highly predictive of LFLE. Seizures arising from the lateral convexity and mesial regions were differentiated by a high incidence of repetitive epileptiform activity at ictal onset in the former and rhythmic theta activity in the latter. CONCLUSIONS: With the exception of mesial frontal lobe epilepsy, ictal recordings are very useful in the localization/lateralization of focal seizures. Some patterns are highly accurate in localizing the epileptogenic lobe. One limitation of ictal EEG is the potential for false localization/lateralization in occipital and parietal lobe epilepsies.

Adolescent↗
PubMed2001

Response-adapted radiotherapy in the treatment of pediatric Hodgkin's disease: an interim report at 5 years of the German GPOH-HD 95 trial.

PURPOSE: A multinational trial on pediatric Hodgkin's disease (HD) with the aim to reduce the risk of long-term toxicity of combined modality treatment by restricting dose and volume of radiation therapy (RT) while maintaining the excellent treatment results of previous German multicenter trials (DAL-HD82-90). METHODS AND MATERIALS: Patients were treated according to stage of disease (CS) and defined risk factors in three treatment groups (TG) with 2, 4, or 6 cycles of combination chemotherapy. When a complete remission (CR) had been achieved, treatment was terminated without RT independent of initial stage or tumor bulk. Patients with a partial remission (PR) of >75% tumor regression were irradiated with 20 Gy using modified involved fields; in the case of PR <75% RT dose was 30 Gy, residual masses >50 mL received 35 Gy. RESULTS: From August 1995 to July 2000 a total of 956 patients have been registered, 830 as trial patients, 39% in TG1, 27% in TG2, 34% in TG3. 827 patients were evaluable by June 2001 with a median follow-up of 38 months. Chemotherapy (CTx) resulted in CR in 22%, PR >75% in 62%, PR <75% in 12%. Event-free survival (EFS) for the entire group is 90% (SD 0.01), for TG1 94%, TG2 91%, and TG3 84%; the overall survival is 97% in Kaplan-Meier-analysis. Relapse-free survival (RFS) is superior for patients with RT after PR (93%) than for those without RT after CR (89%); the difference is significant (p = 0.01) for advanced stages, however not in TG1. Seventy-two events were observed by June 2001: 28 progressions during the initial therapy or within the first 3 months, 38 relapses, 3 second malignancies, three fatal accidents or infections; 18 patients have died. CONCLUSION: Treatment results of the GPOH-HD 95 trial are excellent thus far. The reduction of RT dose and volume in PR has not caused a significant impairment of overall and event-free survival in comparison to the previous German trials; however, failure rates are higher in advanced stages when RT is omitted after achieving a CR. It is too early to tell whether the HD 95 protocol will be successful in reducing late toxicity.

Adolescent↗
PubMed2001

Painful auras in focal epilepsy.

The authors studied the localizing or lateralizing value of painful epileptic auras in 25 patients with focal epilepsy. Painful auras were seen in 4.1% patients with focal epilepsy arising from temporal, frontal, perirolandic, or parieto-occipital regions. Abdominal pain was present in 5% of all abdominal auras in temporal lobe epilepsy and 50% of all abdominal auras in frontal lobe epilepsy. In perirolandic epilepsy, painful somatosensory auras were lateralized contralateral to the epileptic hemisphere but not consistently in temporal lobe epilepsy.

Abdominal Pain↗
PubMed2001

Temporal lobe epilepsy due to hippocampal sclerosis in pediatric candidates for epilepsy surgery.

OBJECTIVE: To characterize the clinical, EEG, MRI, and histopathologic features and explore seizure outcome in pediatric candidates for epilepsy surgery who have temporal lobe epilepsy (TLE) caused by hippocampal sclerosis (HS). METHODS: The authors studied 17 children (4 to 12 years of age) and 17 adolescents (13 to 20 years of age) who had anteromesial temporal resection between 1990 and 1998. RESULTS: All patients had seizures characterized by decreased awareness and responsiveness. Automatisms were typically mild to moderate in children and moderate to marked in adolescents. Among adolescents, interictal spikes were almost exclusively unilateral anterior temporal, as opposed to children in whom anterior temporal spikes were associated with mid/posterior temporal, bilateral temporal, extratemporal, or generalized spikes in 60% of cases. MRI showed hippocampal sclerosis on the side of EEG seizure onset in all patients. Fifty-four percent of children and 56% of adolescents had significant asymmetry of total hippocampal volumes, whereas the remaining patients had only focal atrophy of the hippocampal head or body. Subtle MRI abnormalities of ipsilateral temporal neocortex were seen in all children and 60% of adolescents studied with FLAIR images. On histopathology, there was an unexpectedly high frequency of dual pathology with mild to moderate cortical dysplasia as well as HS, seen in 79% of children and adolescents. Seventy-eight percent of patients were free of seizures at follow-up (mean, 2.6 years). A tendency for lower seizure-free outcome was observed in patients with bilateral temporal interictal sharp waves or bilateral HS on MRI. The presence of dual pathology did not portend poor postsurgical outcome. CONCLUSIONS: TLE caused by HS similar to those in adults were seen in children as young as 4 years of age. Focal hippocampal atrophy seen on MRI often was not reflected in total hippocampal volumetry. Children may have an especially high frequency of dual pathology, with mild to moderate cortical dysplasia as well as HS, and MRI usually, but not always, predicts this finding. Postsurgical seizure outcome is similar to that in adult series.

Adolescent↗
PubMed2001

Presurgical evaluation of epilepsy.

An overview of the following six cortical zones that have been defined in the presurgical evaluation of candidates for epilepsy surgery is given: the symptomatogenic zone; the irritative zone; the seizure onset zone; the epileptogenic lesion; the epileptogenic zone; and the eloquent cortex. The stepwise historical evolution of these different zones is described. The current diagnostic techniques used in the definition of these cortical zones, such as video-EEG monitoring, MRI and ictal single photon emission computed tomography, are discussed. Established diagnostic tests are set apart from procedures that should still be regarded as experimental, such as magnetoencephalography, dipole source localization and spike-triggered functional MRI. Possible future developments that might lead to a more direct definition of the epileptogenic zone are presented.

Electroencephalography↗
PubMed2000

Seizure outcome after surgery for epilepsy due to malformation of cortical development.

PURPOSE: To explore seizure outcome after surgery for focal epilepsy due to malformation of cortical development (MCD), with focus on the role of MRI. METHODS: Thirty-five patients who had surgery for intractable focal epilepsy due to MCD identified by preoperative MRI and confirmed by histopathologic analysis of resected tissue were studied. Patients were aged 3 months to 47 years (median, 14 years) at the time of surgery. Duration of follow-up was 1 to 7.9 (mean, 3.4) years. RESULTS: At latest follow-up, 17 patients (49%) had Engel Class I outcome with no seizures or auras only; eight patients (23%) had Class II outcome, with rare disabling seizures; seven patients (20%) had worthwhile improvement; and three patients (9%) had no improvement. Seizure-free outcome tended to be more frequent among patients who had complete resection of unilateral MCD (excluding hemimegalencephaly) based on postoperative MRI (7/12; 58%), compared with patients with unilateral MCD who had incomplete resection (3/11; 27%), but the difference was not significant. The frequency of seizure-free outcome did not differ significantly between children (8/14; 57%), adolescents (7/15; 47%) or adults (2/6; 33%); between patients who had daily (12/24; 50%), weekly (4/9; 44%), or monthly (1/2; 50%) seizures preoperatively; between patients who had temporal (2/6; 33%) or extratemporal or multilobar resections (14/28; 50%); or between patients who were (9/16; 56%) or were not (8/19; 42%) studied with subdural electrodes. Results for all analyses were similar when analyzed at latest available follow-up or at 1 year after surgery. CONCLUSIONS: Surgery can offer seizure-free outcome for approximately one half of carefully selected patients with intractable focal epilepsy due to MCD. Complete resection of the MRI-apparent lesion may improve the likelihood for favorable outcome. MRI evidence of hemimegalencephaly or bilateral MCD suggests a low likelihood for postoperative freedom from seizures.

Adolescent↗
PubMed1999

Hippocampal volumetry in children 6 years or younger: assessment of children with and without complex febrile seizures.

PURPOSE: To study the relationship of complex febrile seizures (CFS) in the evolution of mesial temporal sclerosis. METHODS: We studied five children 22-68 (mean 44) months old with MRI volumetry 2 days-46 months after their first CFS, and compared total hippocampal volumes and right to left hippocampal volume ratios to those of 11 controls, 15-83 (mean 55) months old, who had MRI for complaints which turned out to be neurologically insignificant. RESULTS: In control children, total hippocampal volumes increased linearly with age, while right to left hippocampal volume ratios tended to decrease with age. In children with CFS total hippocampal volumes tended to be smaller than in controls. Right to left ratios were greater than 1 in all five children with CFS compared to seven of 11 controls. Hippocampal asymmetry was noted in only one child, with the right to left volume ratio exceeding two standard deviations from the control mean. The MRI of this child also demonstrated a subarachnoid cyst in the left frontocentral region, ipsilateral to the smaller hippocampus. Visual inspection of the remaining patients revealed no definite structural cortical abnormalities. None of the children developed subsequent afebrile seizures during the brief follow-up period. CONCLUSIONS: Hippocampal volumetry in controls revealed a linear increase in total hippocampal volumes and a statistically nonsignificant trend toward reduced right larger than left hippocampal ratios between 17 and 83 months old. The tendency for smaller total hippocampal volumes and larger right to left hippocampal volume ratios in children with CFS compared to controls could suggest a developmental abnormality, injury during CFS, or be age-related. The significant hippocampal asymmetry in a single child with CFS suggests that age may not be a factor in every case. Further studies are needed to collect control data in young children as well as prospectively follow children with CFS with serial imaging to better understand the relationship between CFS and the evolution of hippocampal atrophy.

Aging↗
PubMed1999

A new epileptic seizure classification based exclusively on ictal semiology.

Historically, seizure semiology was the main feature in the differential diagnosis of epileptic syndromes. With the development of clinical EEG, the definition of electroclinical complexes became an essential tool to define epileptic syndromes, particularly focal epileptic syndromes. Modern advances in diagnostic technology, particularly in neuroimaging and molecular biology, now permit better definitions of epileptic syndromes. At the same time detailed studies showed that there does not necessarily exist a one-to-one relationship between epileptic seizures or electroclinical complexes and epileptic syndromes. These developments call for the reintroduction of an epileptic seizure classification based exclusively on clinical semiology, similar to the seizure classifications which were used by neurologists before the introduction of the modern diagnostic methods. This classification of epileptic seizures should always be complemented by an epileptic syndrome classification based on all the available clinical information (clinical history, neurological exam, ictal semiology, EEG, anatomical and functional neuroimaging, etc.). Such an approach is more consistent with mainstream clinical neurology and would avoid the current confusion between the classification of epileptic seizures (which in the International Seizure Classification is actually a classification of electroclinical complexes) and the classification of epileptic syndromes.

Electroencephalography↗
PubMed1998

Semiological seizure classification.

We propose an epileptic seizure classification based exclusively on ictal semiology. In this semiological seizure classification (SSC), seizures are classified as follows: a. Auras are ictal manifestations having sensory, psychosensory, and experiential symptoms. b. Autonomic seizures are seizures in which the main ictal manifestations are objectively documented autonomic alterations. c. "Dialeptic" seizures have as their main ictal manifestations an alteration of consciousness that is independent of ictal EEG manifestations. The new term "dialeptic" seizure has been coined to differentiate this concept from absence seizures (dialeptic seizures with a generalized ictal EEG) and complex partial seizures (dialeptic seizures with a focal ictal EEG). d. Motor seizures are characterized mainly by motor symptoms and are subclassified as simple or complex. Simple motor seizures are characterized by simple, unnatural movements that can be elicited by electrical stimulation of the primary and supplementary motor area (myoclonic, tonic, clonic and tonic-clonic, versive). Complex motor seizures are characterized by complex motor movements that resemble natural movements but that occur in an inappropriate setting ("automatisms"). e. Special seizures include seizures characterized by "negative" features (atonic, astatic, hypomotor, akinetic, and aphasic seizures). The SSC identifies in detail the somatotopic distribution of the ictal semiology as well as the seizure evolution. The advantages of a pure SSC, as opposed to the current classification of the International League Against Epilepsy (ILAE), which is actually a classification of electroclinical syndromes, are discussed.

Electroencephalography↗
PubMed1998

Olfactory epileptic auras.

BACKGROUND: Olfactory epileptic auras are rare, constituting about 0.9% of all auras, and are typically described as unpleasant. They have usually been associated with tumors, but in some recent studies they have not. METHODS: We identified 13 patients (7 male, 6 female) with olfactory epileptic auras from 1423 patients with partial epilepsy evaluated for intractable seizures between 1991 and 1996. All had routine EEGs and MRI. Twelve underwent prolonged video-EEG monitoring. RESULTS: Olfactory sensations were of various types but unpleasant in only seven. Auras evolved to complex partial seizures (automotor, hypermotor, or dialeptic seizures) in 12 patients, with further evolution to generalized tonic-clonic seizures in three and aphasic seizures in one patient. The EEG focus was localized to the mesial temporal region in all. Ten patients had a mesial temporal tumor; in one patient, it extended to the superior temporal gyrus, and in another, the frontal lobe. The tumor involved only the amygdala in two patients and both amygdala and hippocampus in six; none had hippocampal involvement alone. Surgery was performed in nine patients. All except one with partial tumor resection had a seizure-free outcome. This patient also became seizure-free after repeat surgery to remove residual tumor tissue in the amygdala. CONCLUSIONS: Olfactory auras are not necessarily unpleasant. The amygdala is the most likely symptomatogenic zone of olfactory auras. Tumors are the commonest etiology; mesial temporal sclerosis is a relatively rare cause.

Adolescent↗
PubMed1997

Ictal motor signs and interictal regional cerebral hypometabolism.

Early motor manifestations are the main components of focal seizures involving the frontal lobe. We examined the relationship between the initial ictal motor manifestations and interictal abnormalities of cerebral glucose consumption (rCMRGlc) as assessed by PET in 48 consecutive patients with focal seizures of neocortical origin. Group data analysis revealed that patients with predominantly unilateral clonic seizures had a significant contralateral perirolandic hypometabolism and to a lesser degree a contralateral frontomesial hypometabolism. Patients with predominantly focal tonic manifestations showed a hypometabolism within the frontomesial and perirolandic regions that was unilateral in all patients with lateralized tonic seizures. Patients with versive seizures had mainly contralateral metabolic depressions without a consistent regional pattern. Patients with hypermotor seizures had metabolic depressions involving frontomesial, anterior cingulate, perirolandic, and anterior insular/frontal operculum areas. In all patient groups, bilateral and symmetric hypometabolism of the thalamus and cerebellum was observed. We propose that this pattern of distinctly abnormal metabolic brain regions demonstrates not only possible epileptogenic zones but also symptomatogenic brain regions as shown by the associations between clinical manifestations and sets of abnormal brain regions, particularly if epileptogenic zones are in a clinically silent neocortical brain region. The detection and possible differentiation of symptomatogenic and epileptogenic zones might improve the effectiveness of presurgical noninvasive studies.

Adult↗
PubMed1996

Brain-stem auditory evoked potentials (BAEPs) from basal surface of temporal lobe recorded from chronic subdural electrodes.

BAEPs were recorded from the basal surface of the temporal lobe by subdural electrodes chronically implanted in 6 patients who were evaluated for surgical management of intractable partial seizures. Near-field recordings were obtained by recording between the subdural electrode closest and most distant to the brain-stem. Far-field recordings were obtained by recording between the subdural electrodes and an indifferent electrode over the spinal process of the seventh cervical vertebrae. The recordings were compared with standard ear-vertex recordings. After ipsilateral ear stimulation, the subdural electrode closest to the brain-stem recorded large amplitude waves I and II followed by less well-defined waves of longer latencies. Recordings to contralateral stimulation showed no clearly defined waves I and II and a large amplitude wave Vn. Waves III, IV, V, Vn and VI were of opposite polarity after ipsi- and contralateral stimulation. These findings indicate that waves I and II are generated ipsilaterally to the stimulation side, whereas wave Vn has a contralateral origin. Wave Vn may be generated in the brachium of the inferior colliculus, as suggested from dipole configuration studies. This conclusion is consistent with the classical anatomical observations that the supracollicular auditory pathways are predominantly crossed.

Acoustic Stimulation↗
PubMed1996

Topography of interictal glucose hypometabolism in unilateral mesiotemporal epilepsy.

We mapped the regional cerebral glucose metabolism (rCMRGlu) in 20 patients suffering from medically refractory focal epilepsy of either left or right mesiotemporal origin (mTLE) during resting wakefulness. After temporal lobectomy, histology demonstrated hippocampal sclerosis in 18 patients. Pixel-by-pixel comparisons with healthy control subjects showed significant (p < 0.001) depressions of the mean rCMRGlu ipsilateral to the epileptic focus in the mesiotemporal region, including the hippocampus and the parahippocampal gyrus and middle temporal gyrus. Additional remote rCMRGlu depressions occurred bilaterally in the fronto-orbital cortex and ipsilaterally in the posterior insula and the thalamus. Patients with left-sided mTLE had additional rCMRGlu depressions in the left inferior frontal gyrus (Broca's region) and superior temporal gyrus at the parietotemporal junction, whereas corresponding rCMRGlu depressions were not present in patients with right mTLE. Neuropsychological testing showed impaired verbal fluency, verbal intelligence, and verbal memory in the left mTLE patients. Correlations of the specific mean rCMRGlu depressions and the neuropsychological deficits suggest that impaired language functions in patients with left mTLE could result from functional changes beyond the temporal lobe.

Adolescent↗
PubMed1995

[Classification of epileptic seizures. Comparison of two systems].

In spite of its universal acceptance, the international classification of epileptic seizures suffers from certain limitations. The fundamental divisions between partial and generalized seizures on the one hand, and between partial simple and complex seizures on the other, are not always practical, nor useful. The terminology is often cumbersome, and does not contain essential localizing information. Finally, the seizure classification is sometimes dependent on ancillary testing, particularly the EEG. We propose a different seizure classification, which answers the above shortcomings of the international classification, and which has been used for years in major epilepsy centers. In this system, the seizure classification is based exclusively on seizure symptomatology. The terms are generally more concise than those of the international classification, and yet convey more precise information. For example, the term left visual aura-->automotor seizure-->generalized tonic clonic seizure would be equivalent to simple partial seizure with visual symptom evolving into complex partial seizure evolving into generalized tonic clonic seizure. The international classification is longer and omits essential later-alizing information. This classification is easy to apply, and can be an extremely useful complement to the international seizure classification, especially for centers whose emphasis is on surgical treatment of epilepsy.

Behavior↗
PubMed1995

Frontal lobe seizures: electroclinical syndromes.

To define further the electroclinical manifestations of frontal lobe epilepsy (FLE), we studied 150 seizures manifested by 24 patients; 18 patients had subdural electrode arrays (SEA). The findings in these patients clearly overlapped presumably reflecting the interconnections between functionally related frontal zones; yet the manner in which the symptoms clustered and the sequence in which they occurred generally indicated the anatomic site of the epileptogenic zone. We divided the patients into three major groups: (a) those with supplementary motor seizures, (b) those with focal motor seizures, and (c) those with complex partial seizures (CPS, psychomotor seizures). Supplementary motor seizures began with tonic posturing of the extremities. Focal motor seizures generally began with conscious contralateral version or unilateral clonic focal motor activity; tonic posturing was noted only late in the seizure. CPS (psychomotor) began with unresponsiveness at onset, followed by staring or unconscious contraversion. We compared frontal lobe seizures with temporal lobe seizures reported previously; oral-alimentary automatisms, repetitive hand movements, or looking around, were more common in temporal lobe seizures, whereas tonic posturing and bicycling movements were more common in frontal lobe psychomotor seizures.

Adolescent↗
PubMed1995

Propagation of interictal epileptic activity in temporal lobe epilepsy.

We recorded interictal spikes with closely spaced scalp electrodes and sphenoidal electrodes in four patients with temporal lobe epilepsy. We used multiple dipole modeling to study the number, three-dimensional intracerebral location, time activity, and functional relationship of the neuronal sources underlying the epileptic spike complexes. In all patients, we found two significant sources generating the interictal spikes which showed considerable overlap in both space and time. Source 1 was located in the mesiobasal temporal lobe and generated a restricted negativity at the ipsilateral sphenoidal electrode and a widespread positivity over the vertex. Source 2 could be attributed to the lateral temporal neocortex and was associated with a relatively restricted negativity at the ipsilateral temporal electrodes and a more widespread positivity over the contralateral hemisphere. The sources were well separated in space, with an average distance of 45 mm between them. The time activities of both sources showed similar biphasic patterns, with the mesial source leading the lateral source by approximately 40 msec, suggesting propagation of interictal epileptic activity from the mesiobasal to the lateral temporal lobe.

Adult↗