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Featured researches published by Norfrid Klug.


Surgical Neurology | 1997

Chronic subdural hematoma: Surgical treatment and outcome in 104 patients

Ralf-Ingo Ernestus; Piotr Beldzinski; Heinrich Lanfermann; Norfrid Klug

BACKGROUND The common occurrence of chronic subdural hematoma (CSDH) in older patients raises some diagnostic and therapeutic difficulties. Despite general agreement about the indication of operation, the extent of surgery is still discussed controversially. We have, therefore, reviewed operative findings and outcome in 104 patients with CSDH. METHODS Retrospective analysis was performed by differentiating age < or = 60 years (n = 28) versus age > 60 years (n = 76) and burr hole craniostomy with a size range from 12-30 mm (n = 94) versus larger craniotomy (n = 10). All patients received closed-system drainage of the subdural space for 2-4 days. RESULTS Four patients older than 60 years died within 30 days after surgery, two in each operative group. Excluding these postoperative deaths, 17 out of 92 patients (18.5%) after burr hole trepanation and one out of eight patients (12.5%) after craniotomy required reoperation due to rebleeding (n = 6), residual subdural fluid (n = 4), and residual thick hematoma membranes (n = 8). Eight patients, who had been initially treated by burr hole craniostomy despite preoperative detection of neomembranes by contrast-enhanced computed tomography (CT) or magnetic resonance imaging (MRI), recovered without further intervention. Clinical outcome was good in both operative groups. The percentage of patients without or with only mild neurologic deficits at the time of discharge from the hospital was 72.3% in the burr hole and 70.0% in the craniotomy group, respectively. CONCLUSIONS The clinical data of the present study suggest that burr hole craniostomy with closed-system drainage should be the method of choice for the initial treatment of CSDH, even in cases with preoperative detection of neomembranes. Craniotomy should be carried out only in patients with reaccumulating hematoma or residual hematoma membranes, which prevent reexpansion of the brain.


Neuroscience Letters | 2001

Age related signal decrease in functional magnetic resonance imaging during motor stimulation in humans

Volker Hesselmann; Olivier Zaro Weber; Christoph Wedekind; Timo Krings; Oliver Schulte; Harald Kugel; Barbara Krug; Norfrid Klug; K. Lackner

Right handed healthy volunteers underwent functional magnetic resonance imaging (fMRI) examinations on a 1.5 Tesla MRI-scanner (Gyroscan ACS NT; Philips, Best, NL). Blood oxygen level dependent (BOLD) images were obtained using a three dimensional multi-shot echo planar imaging sequence employing a shifted echo technique (Principles of echo shifting with a train of observations). Finger tapping of the right hand was used as a task for motor stimulation. A total of 86 subjects was included into statistical analysis. Absolute and relative signal differences and cluster sizes of activation for the left motor cortex were obtained. In addition, Z-score, pooled Z-score and cross correlation activation maps were calculated and matched with high resolution anatomic images. A significant decrease with age could be detected for absolute and relative signal intensity differences for the whole group and for the male subgroup. Correlation analysis for the female subgroup also bore negative albeit non-significant correlation coefficients. An age-related decline of BOLD-contrast can be assumed to explain signal decrease. This age-related effect should be considered in clinical fMRI applications.


Spine | 1998

Acute nontraumatic spinal epidural hematomas : An important differential diagnosis in spinal emergencies

Chariklia Alexiadou-Rudolf; Ralf-Ingo Ernestus; Kimon Nanassis; Heinrich Lanfermann; Norfrid Klug

Study Design. The clinical data of five patients with spontaneous spinal epidural hematoma (SSEH) were reviewed. Objectives. To assess the clinical outcome of patients with SSEH after surgical decompression. Summary of Background Data. The outcome in SSEH is essentially determined by the timing of the operation. Therefore, early and precise diagnosis is necessary. Methods. A retrospective analysis of five patients with SSEH was performed. The clinical data were stratified according to the Frankel Score. Special interest was given to the relevance of rapid and exact diagnosis and immediate therapeutic intervention. Results. Diagnosis of SSEH was established preoperatively by means of computed tomography (one case) or magnetic resonance imaging (three patients) and intraoperatively in one case. Lumbar myelography had been false negative in one patient, computed tomography false‐negative in two patients. Surgical decompression was performed in four patients within 24 hours after the onset of symptoms. Favorable postoperative functional results were found only in one patient whose symptoms had been present for less than 12 hours and in the case of an incomplete cauda equina syndrome. Conclusions. The results of the current series demonstrate both the superiority of magnetic resonance imaging for diagnosis of SSEH as well as the necessity of early decompressive surgery in cases of sensorimotor paralysis after SSEH.


Neurosurgery | 2000

Multiple Interstitial Substances Measured by Microdialysis in Patients with Subarachnoid Hemorrhage

Frank Staub; Rudolf Graf; Paula Gabel; Matthias Köchling; Norfrid Klug; Wolf-Dieter Heiss

OBJECTIVEIntracerebral microdialysis is a tool to monitor metabolic disturbances in the brains of patients with severe head injuries or subarachnoid hemorrhage (SAH). In the search for putative indicators of primary and secondary brain damage, we measured multiple metabolites in the dialysates of patients with SAH, to elucidate their significance for the outcomes of the patients as well as their temporal profiles of liberation after the insult. METHODSMicrodialysis probes were placed, with a ventriculostomy catheter for drainage of cerebrospinal fluid, into a frontal lobe of 10 patients with aneurysmal SAH, for 4.6 ± 0.5 days. Amino acids, metabolites of glycolysis, purines, catecholamines, and nitric oxide oxidation byproducts were measured by high-performance liquid chromatography. Spearman’s correlation coefficient and Student’s t test were used to compare the levels of the metabolites with the outcomes of the patients, as assessed using the Glasgow Outcome Scale, 3 months after the ictus. RESULTSFor patients with unfavorable outcomes (Glasgow Outcome Scale scores of 1–3), which were primarily associated with the development of large infarctions, dialysate levels of excitatory amino acids increased up to 30-fold, those of lactate up to 10-fold, and those of nitrite up to 5-fold, compared with normal levels observed for patients with favorable outcomes (Glasgow Outcome Scale scores of 4 or 5). When average peak concentrations in the dialysates of patients with favorable and unfavorable outcomes were compared, significantly higher levels of excitatory amino acids, taurine, lactate, and nitrite, but not of purines and catecholamines, were observed for those with poor outcomes (P < 0.05). With respect to the temporal profiles of the average metabolite concentrations, the significantly increased levels of amino acids observed for patients with poor outcomes followed a biphasic course, with maximal concentrations on the first and second days or the seventh day after the insult (P < 0.01). CONCLUSIONThese data confirm the usefulness of excitatory amino acids and lactate as major parameters for neurochemical monitoring for patients threatened by acute cerebral disorders. Other substances, such as taurine and nitrite, were also demonstrated to be potentially predictive. Release of these substances into the extracellular fluid of the brain might be particularly relevant for the development of secondary brain damage after SAH, e.g., infarction or brain swelling.


NeuroImage | 1998

Localization of Language-Related Cortex with15O-Labeled Water PET in Patients with Gliomas

Alexander Thiel; Karl Herholz; Hans-Martin von Stockhausen; Karin van Leyen-Pilgram; U. Pietrzyk; Josef Kessler; Klaus Wienhard; Norfrid Klug; Wolf-Dieter Heiss

Measurement of relative cerebral blood flow (CBF) with 15O-labeled water PET has been widely used for brain mapping experiments on language functions in normal volunteers and patients with epilepsy. We focused on the question of whether PET during speech activation is an appropriate method for noninvasive determination of language-related cortex in patients with brain tumors. Furthermore, the suitability of the method for determination of hemispheric language dominance was examined and compared to the results of the Edinburgh Handedness Inventory. Ten right-handed and six left-handed patients with gliomas were examined prior to surgery while repeatedly performing word repetition and verb generation tasks. A set of volumes of interest (VOIs) was drawn on coregistered MRI in order to account for anatomic variability as well as anatomical alterations due to tumor mass effect. Repetition of nouns did not produce significant hemispheric differences. During stimulation by verb generation, reliable lateralized activations of Brocas area and supplementary motor area were detected in all right-handed patients. Of the left-handed patients, two showed clear right lateralization, two activated Brocas area bilaterally, and two had a pattern similar to that of right-handers. Patients with bilateral activations showed the strongest tendency toward bihandedness according to the handedness inventory. Lateralization of supplementary motor area in left-handers corresponded to lateralized activity in Brocas area. Tumors in the vicinity of language-related regions did not alter activation responses. In conclusion, measurement of CBF changes during verb generation permits identification of language-related areas in patients with gliomas with strong lateralization related to hemispheric dominance. These findings may be of particular clinical interest for left-handed patients.


Brain Injury | 2007

Health-related quality of life during the first year after severe brain trauma with and without polytrauma.

Marcela Lippert-Grüner; Marc Maegele; Heinz Haverkamp; Norfrid Klug; Christoph Wedekind

Objective: The increasing number of patients surviving severe traumatic brain injury (sTBI) but with significant sensorimotor and neuropsychological deficits is a challenge to rehabilitation medicine. So far, most research initiatives have focused on mortality rates, physiological or economic parameters to estimate therapeutic effects of rehabilitation strategies. Investigations on health-related quality of life (HRQoL) after TBI with and without concomitant polytrauma are rare compared to other disorders. Design/patients: A prospective study was conducted to investigate HRQoL using the SF-36 questionnaire in 49 patients with sTBI (Glasgow Coma Scale < 9 for more than 24 hours) with and without concomitant polytrauma 6 and 12 months after injury. Results: The SF-36 score profiles 6 and 12 months after trauma were similar. Scores 12 months after trauma, however, were higher in 7/8 dimensions indicating an improvement over time. Similar observations were made for physical and mental sum scores. There was no difference in the SF-36 scoring pattern between the patients with isolated TBI and the patients with concomitant polytrauma, except for physical functioning after 12 months. Conclusion: While there is significant overall improvement of HRQoL over time, sTBI appears to bear major influence on post-traumatic HRQoL and outcome.


Childs Nervous System | 1996

Prognostic relevance of localization and grading in intracranial ependymomas of childhood.

Ralf-Ingo Ernestus; Roland Schröder; Hartmut Stützer; Norfrid Klug

Intracranial ependymomas represent one of the most frequent brain tumors in childhood. Their preferred midline localization and their often controversially discussed classification prompted the present study of 67 intracranial ependymomas in children less than 15 years of age who were operated on from 1951 to 1990. Clinical data and follow-up of all children were retrospectively analyzed by calculation and statistical comparison of progression-free survival (PFS). According to the WHO classification as revised in 1993, 1 grade I subependymoma, 38 grade II ependymomas, and 28 grade III anaplastic (malignant) ependymomas were differentiated. Grade II ependymomas were predominantly located in the IV ventricle and in the supratentorial midline, which often made complete tumor resection impossible. In contrast, the majority of grade III tumors, most often situated in the cerebral hemispheres, could be totally removed. Operative mortality was higher in grade II than in grade III tumors. After recovery from operation, PFS was mainly determined by the histological grading. Median postoperative PFS was 120 months in grade II, but only 18 months in grade III ependymomas (P = 0.1417). Thus, despite varying therapeutic concepts, analysis of this 40-year collective study confirms the prognostic relevance of localization and WHO grading in the case of intracranial ependymoma in children.


Acta Neurochirurgica | 2005

Spinal epidural abscess: prognostic factors and comparison of different surgical treatment strategies.

M. Löhr; Thomas Reithmeier; Ralf-Ingo Ernestus; Heinrich Ebel; Norfrid Klug

SummaryBackground. Spinal epidural abscess (SEA) is a rare but potentially devastating disease requiring immediate surgical intervention and appropriate antibiotic treatment. The standard approach to decompress SEA is laminectomy. No report covers comprehensively the indications for the less invasive interlaminar approach, the usefulness of intra-operative ultrasonography and the suspected benefit of inserting a suction-irrigation drainage.Method. A retrospective evaluation of the medical and radiological data was undertaken in 27 consecutive patients with SEA operated on during a period of 10 years by a dorsal approach. Factors influencing outcome were evaluated with special regard to different surgical strategies concerning the invasiveness of the operative approach, the use of intra-operative ultrasound and the use of different drainage systems.Findings. Outcome was mainly determined by the pre-operative neurological condition and the localization of the abscess. Recurrence rate was dependent on the longitudinal extent of the mass and the intra-operative finding of granulation tissue, but not on the administration of a postoperative suction-irrigation drainage. An interlaminar approach was equally matched to a decompression by laminectomy in lumbar SEA concerning the incidence of residual/recurrent abscess formation. In concomitant spondylodiscitis, laminectomy bore the risk of the formation of a postoperative kyphotic deformity. The use of intra-operative ultrasound allowed the visualization of hidden inflammatory masses and, thus, reduced the rate of residual abscess formation.Conclusion. An interlaminar approach should be considered instead of laminectomy in lumbar SEA and in impending anterior column instability due to spondylitis. Intra-operative ultrasound is a beneficial aid for the determination of the extent of decompression during surgery and is practicable even through a narrow interlaminar bony window. The insertion of postoperative suction-irrigation drainage had no beneficial effect on outcome but bore the risk of epidural fluid congestion.


Brain Injury | 2006

Neurobehavioural deficits after severe traumatic brain injury (TBI)

Marcella Lippert-Grüner; Johannes Kuchta; Martin Hellmich; Norfrid Klug

Objectives: Debilitating neurobehavioural sequalae often complicate traumatic brain injury (TBI). Cognitive deficits, particularly of attention, memory, information-processing speed and problems in self-perception, are very common following severe TBI. Method: The Neurobehavioural Rating Scale (NRS) is a multi-dimensional clinical-based assessment instrument designed and validated to measure neurobehavioural disturbances following TBI. This study examined 41 patients who were admitted to the intensive care unit of the Department of General Neurosurgery at Cologne University Hospital after severe TBI between January 1995 and July 2003. All 27 items of the NRS were assessed 6 and 12 months post-injury. Results: Subjects after severe TBI (GCS<9) showed relatively high overall scores on the NRS, reflecting a high degree of overall neurobehavioural dysfunction. NRS items did not change significantly between 6 and 12 months post-trauma for anxiety, expressive deficit, emotional withdrawal, depressive mood, hostility, suspiciousness, fatigability, hallucinatory behaviour, motor retardation, unusual thought content, liability of mood and comprehension deficit. There was a tendency of improvement for inattention, somatic concern, disorientation, guilt feelings, excitement, poor planning and articulation deficits. For conceptual disorganization, disinhibition, memory deficit, agitation, inaccurate self-appraisal, decreased initiative, blunted affect and tension even a tendency for further deterioration in the post-traumatic follow-up was detected. Changes between 6 and 12 months post-TBI were statistically significant for disorientation (improvement), inattention/reduced alertness (improvement) and excitement (deterioration). Conclusion: The data shows that neurobehavioural deficits after TBI do not show a general tendency to disappear over time. Some aspects related to self-appraisal, conceptual disorganization and affect may even deteriorate, thereby presenting a challenging problem for both the patients and relatives. This is in contrast to the parallel improvement of post-traumatic sensomotoric deficits.


European Journal of Neuroscience | 2005

Multimodal early onset stimulation combined with enriched environment is associated with reduced CNS lesion volume and enhanced reversal of neuromotor dysfunction after traumatic brain injury in rats

Marc Maegele; Marcela Lippert-Gruener; Thorsten Ester-Bode; Janika Garbe; Bertil Bouillon; E. Neugebauer; Norfrid Klug; Rolf Lefering; Wolfram F. Neiss; Doychin N. Angelov

This study was designed to determine whether exposure to multimodal early onset stimulation (MEOS) combined with environmental enrichment (EE) after traumatic brain injury (TBI) would improve neurological recovery and to elucidate its morphological correlates. Male Sprague–Dawley rats were subjected to lateral fluid percussion (LFP) brain injury or to sham operation. After LFP, one‐third of the animals (injured and sham) were placed under conditions of standard housing (SH), one‐third were kept in EE only, and one‐third received EE + MEOS. Assessment of neuromotor function 24 h post‐injury using a standardized composite neuroscore test revealed an identical pattern of neurological impairment in all animals subjected to LFP. Neuromotor dysfunction in SH animals remained on a similar level throughout the experiment, while improvements were noted in both other groups 7 days post‐injury (dpi). On 15 dpi, reversal of neuromotor dysfunction was significantly better in EE + MEOS animals vs. SH‐ and EE‐only groups. In parallel, the comparison of lesion volume in EE + MEOS‐ vs. EE‐only vs. SH rats revealed that animals exposed to EE + MEOS had consistently the lowest values (mm3, mean ± SD; n = 6 rats in each group) as measured in serial brain sections immunostained for neuron‐specific enolase (5.2 ± 3.4 ≤ 5.5 ± 4.1 < 9.5 ± 1.9), caspase 3‐active/C3A (5.9 ± 4.0 ≤ 6.4 ± 3.9 < 10.3 ± 1.8) and glial fibrillary acidic protein (6.0 ± 3.4 ≤ 6.5 ± 4.3 < 10.7 ± 1.2). This first report on the effect of EE + MEOS treatment strongly indicates that the combined exposure reduces CNS scar formation and reverses neuromotor deficits after TBI in rats.

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Ebel H

University of Cologne

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M. Löhr

University of Cologne

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