H. Arnold
University of Lübeck
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Acta Neurochirurgica | 1994
Georg Nowak; Rolf Schwachenwald; H. Arnold
SummaryAneurysm surgery began in Lübeck only in 1986 when the department was completely reorganized. Early operation in the good grade patients (I–III, according to Hunt and Hess) was performed. In every case we also discussed the feasibility of operating on the poor grade patients (Hunt and Hess IV and V).During a five-year period (1986–1991) a total of 277 SAH patients were admitted to the department. 109 (39%) patients arrived in a poor grade (Hunt and Hess IV or V), 12 of these patients died within hours of admission. 25 patients, who presented with a large intracerebral and/or subdural haematoma, were urgently operated upon by haematoma evacuation and aneurysm clipping. An external ventricular drainage was performed on 72 patients. Of the ventriculostomy group 33 patients improved and 27 were operated upon. In 17 of the 39 patients without improvement after CSF-drainage we decided to operate.Overall 69 patients were surgically treated (craniotomy, aneurysm clipping) and 40 were not. The mortality rate in the surgical cases was 16 (23%) compared with 30 (75%) without operation.It is concluded that poor grade aneurysm patients can achieve a better outcome with active treatment based on immediate ventriculostomy and optimal haemodynamic parameters after haematoma evacuation and early occlusion of the aneurysm.
British Journal of Neurosurgery | 1989
Athanase J. A. Terzis; Georg Nowak; Oliver Rentzsch; H. Arnold; Joachim Diebold; Gustavo Baretton
The water jet cutting system allows transaction and dissection of biological structures with little bleeding. Structures of higher tissue rigidity remain unchanged while softer tissues are mechanically dissected. In brain tissue, all vessels larger than 20 microns are left intact after the passage of the jet stream with a pressure of up to 5 bar, and therefore vessels can be isolated selectively from the surrounding tissue. Oedema is present adjacent to the cut and no increase of temperature occurs.
Neurosurgical Review | 1998
Georg Nowak; Daniela Schwachenwald; Rolf Schwachenwald; Uwe Kehler; Harald Müller; H. Arnold
During a six-year period (1986–1992) 334 patients with subarachnoid hemorrhage (SAH) were admitted to the Department of Neurosurgery, Medical University of Lübeck, Germany. In 281 patients the SAH was caused by rupture of an intracranial arterial aneurysm, verified by angiography, postmortem examination, or at emergency operation without angiography. In 67 (23.8 %) of the 281 aneurysmal SAH patients the initial computerized tomography (CT) demonstrated an intracerebral hematoma (ICH). An ICH localized in the temporal lobe due to the rupture of a middle cerebral artery (MCA) aneurysm was found in 47 patients (70.2 %). Forty-three patients were considered for surgery with a surgical mortality of 8 (18.6 %). In the group of 19 ICH patients not operated upon, 16 individuals died (84.2%).We therefore advocate active surgical management of ICH patients: hematoma evacuation and aneurysm clipping at the same operation. Emergency surgery in younger patients (grade V) with temporal ICH suggesting the rupture of a MCA or internal carotid artery (ICA) aneurysm can be done without angiography.
Acta Neurochirurgica | 2003
W. Günther; Kai-Ove Skaftnesmo; H. Arnold; A. J. A. Terzis
Summary¶In glioma cells, the stimulatory input of extracellular matrix components and an increased sensitivity to growth factors result in a high proliferative and migratory behaviour. Cell surface receptor interactions play pivotal roles in converging information about conditions in the environment immediately outside the cell. The transduced signal, in turn induces a response within the cell that provokes a specific behaviour.Cellular migration and cell proliferation are interwoven processes that share several common intracellular pathways. The major cross-links are the phosphoinositol phosphate regulating enzymes, PI-3 kinase and PTEN, the focal adhesion kinase (FAK) and the tumour suppressor p53. An understanding of the interaction between the molecular participants involved in migration and proliferation will promote the design of new treatments.A full understanding of the basis of the invasiveness of tumour cells remains elusive. Gene and protein expression are being studied, using modern techniques such as microarray analysis, SAGE and 2-D protein gels. Transient and permanent protein–protein interactions and recruitment of proteins to specialised cellular domains are equally important in regulating cellular invasion and presumably will attract more attention in future.
Clinical Neurology and Neurosurgery | 1999
Jan Gliemroth; Georg Nowak; H. Arnold
Two cases of dural arteriovenous malformation (AVM) at the base of the anterior cranial fossa are described. In both cases an intracerebral hematoma following the rupture of the AVM was the first indication of the disease. In one case, the malformation was supplied both by the anterior ethmoidal artery and frontopolar artery draining into the superior sagittal sinus. In the second case, the right anterior ethmoidal artery with draining veins into the superior sagittal sinus and sphenoparietal sinus was the feeding vessel. Surgical evacuation of the hematoma and excision of the malformation was performed on both patients. The typical clinical signs and radiological findings are described. A review of the pertinent literature is given.
Neurosurgical Review | 1993
H. Arnold; Feldmann U; Ulrich Missler
In the past, chronic spondylogenic cervical myelopathy has been thought of being a disease often resistent to neurosurgical therapy. 56 out of 70 patient treated by laminectomy or different ventral fusion procedures improved immediately following operation. Only 36, however, continued to be improved at follow-up 5 to 8 years later, whereas additional 8 had worsened again, and another 5 mean-while had died due to myelopathy. Laminectomy turned out to be the least succesful procedure of treatment. Nevertheless, early diagnosis, early operation, appropriate and individual surgical procedures, careful re-evaluation at follow-up, and — if needed — an early decision for a second-step operation can impressively improve the prognosis.
Acta Neurochirurgica | 1995
Georg Nowak; S. Schwachenwald; Uwe Kehler; Harald Müller; H. Arnold
SummaryAcute subdural haematoma (SDH) secondary to a raptured intracranial aneurysm is a rare event. Out of a total of 292 patients with a verified aneurysm (period 1986–1992) in five cases SDH was the diagnosis on CT-evaluation. One patient was in such a bad condition that no treatment was indicated. The remaining four patients were operated on: craniotomy and haematoma evacuation in two cases, craniotomy for haematoma evacuation and aneurysm-clipping in the other two cases. Two patients died and two achieved a good outcome.
Neurosurgical Review | 1990
Uwe Kehler; H. Arnold; Harald Müller
We present the data of 99 patients operated on for infratentorial pilocytic astrocytoma from 1955 to 1980 at the Neurosurgical Department of the University of Hamburg/West Germany. Twenty-two patients had died. From 56 patients long-term follow-up was obtained. A comparison was done for patients either operated on until 1969 or since 1970, the time when microscopes had been introduced into the operation theatre. The mortality rate clearly dropped with the beginning of the “microsurgical era”, certainly due to other improvements as well, e. g. neurosurgical intensive care. The drop in mortality was not accompanied by an improvement in outcome. Future perspectives of possibly further improving the therapy of pilocytic astrocytomas are outlined.
Neuropathology and Applied Neurobiology | 1994
K. Marienhagen; Paal-Henning Pedersen; A. J. A. Terzis; Ole Didrik Laerum; H. Arnold; Rolf Bjerkvig
Fetal as well as mature neural cells were homografted into the right cerebral hemisphere of adult BD–IX rats. The animals were sacrificed 7 d after implantation, and the localization of implanted cells was visualized by fluorescence and light microscopy. The cell implants were prestained with the fluorescent vital dye 1,1′‐Dioctadecyl –3,3,3′3′‐tetramethylindocarbocyanine perchlorate (Dil) to discriminate between implanted cells and host brain tissue. At the implantation site, the fetal brain cells as well as the cells from immature brain cell aggregates showed diffuse infiltration into the surrounding host brain tissue of up to 0.5 mm. Extensive cell migration along the corpus callosum for up to 5 mm in the coronal and to a lesser extent in the sagittal plane was also observed. In addition, fetal cells were distributed in the subarachnoid space of both cerebral hemispheres and showed a distinct association with larger blood vessels. Cells from mature brain aggregates did not migrate as far as fetal cells and showed only a local infiltration into the host neuropil. Fluorescent microspheres as well as fixed fetal brain cells were implanted, either alone or in combination with vital cells to distin guish between active cell migration and passive cell displacement. The microspheres and the fixed cells were found either localized to the implantation pathway or distributed in the corpus callosum for up to 2 mm in the coronal plane without any dispersion in the sagittal plane. The microspheres also showed an extensive displacement in the subarachnoid space. In vitro co–culture experiments between two immature aggregates showed a complete fusion of the two aggregates during a 96 h culture period. In co–cultures between two mature aggregates complete fusion was not prominent, although the confrontation zone appeared diffuse. Confrontations between a mature and an immature aggregate showed the same pattern of interaction as seen for the two mature aggregates. It is concluded that carbocyanine dyes may be used as a tracer for transplanted cells. Cells from fetal rat brain cell aggregates, opposed to those from mature aggregates, showed extensive migration along well defined anatomical structures in the mature brain. Some of the spread of cells following implantation is probably due to passive movement since inert microspheres will spread into certain areas of the CNS.
Journal of Neuro-oncology | 1998
A-Jorge A. Terzis; Paal-Henning Pedersen; Burt G. Feuerstein; H. Arnold; Rolf Bjerkvig; Dennis F. Deen
The polyamine inhibitor DL-α-difluoromethylornithine (DFMO) is a specific irreversible inhibitor of ornithine decarboxylase which is a rate-limiting enzyme in the polyamine bio-synthesis pathway. The present study describes the effects of DFMO on glioma cell proliferation, migration and invasion using multicellular spheroids from three glioma cell lines (GaMg, U-251 Mg and U-87 Mg). 10 mM DFMO reduced cell migration in the three cell lines by about 30–50%. 1 mM putrescine, added together with DFMO inhibited the DFMO effect. A stronger effect was observed in the growth assay where 10 mM DFMO reduced the spheroid growth, for all cell lines, by 90%. This effect was also reversed by adding 1 mM of putrescine. In vitro tumor cell invasion experiments indicated after 3 days of confrontation, an extensive invasion also after 10 mM DFMO treatment. The brain aggregate volumes were reduced to about the same extent as in the absence of drug, suggesting essentially no effects of DFMO on the invasive process. It is concluded that the tumor spheroids retained their ability to invade normal brain tissue even after DFMO exposure. However, DFMO inhibited spheroid growth and cell migration which supports the notion that cell growth, migration and invasion are biological properties that are not necessarily related to each other.