[Midline and vertex epidural hematomas: clinical aspects, surgical indications and therapy]

Within a group of 315 epidural haematomas treated surgically 8 (2.5%) were located within the midline or at the vertex. The clinical symptoms may be small in frontally located haematomas. Paraparesis is caused by a haematoma localized at the vertex. The latter may be misinterpreted as a spinal trauma. The recognition of the hyperdense blood within the last slices of normal CT scans needs experience. It has been misinterpreted as hyperostosis of the skull. We present a group of eight personal cases. The sagittal skull suture was fractured in seven patients. One patient already had an 11-month history. Four cases were primary and had not been recognized. The prognosis depends on concomitant primary brain injuries. Early diagnosis with operative treatment given the best chance. Polytraumatized patients with concomitant injuries die. Slowly developing haematomas do not require acute surgery by in experienced surgeons. Sagittal sinus laceration must be treated by experienced neurosurgeons. It can be closed by suturing the dura to the bone with implanted collagen. In subacute cases the stiffness of the dura allows no normalization of the dura position. A dural graft is necessary for repositioning.

The role of N-actylglucosaminyl-1,6 anhydro N-acetylmuramyl-L-alanyl-D-glutamyl-meso-diaminopimelic acid-D-alanine for the induction of beta-lactamase in Enterobacter cloacae

The mechanism of beta-lactamase induction in Enterobacter cloacae which is linked to the peptidoglycan recycling, was investigated by HPLC analysis of cell wall fragments in genetically defined cells. It is demonstrated here that the transmembrane protein AmpG transports not only the precursor muropeptide of M-tripeptide (N-acetylmuramyl-L-alanyl-D-glutamyl-meso-diaminopimelic acid), the D-tripeptide (N-actylglucosaminyl-1,6 anhydro N-acetylmuramyl-L-alanyl-D-glutamyl-meso-diaminopimelic acid), but also that of M-tetra-peptide (N-acetylmuramyl-L-alanyl-D-glutamyl-meso-diaminopimelic acid-D-alanine), the D-tetrapeptide (N-actylglucosaminyl-1,6 anhydro N-acetylmuramyl-L-alanyl-D-glutamyl-meso-diaminopimelic acid-D-alanine), into the cytoplasm. These findings indicate that probably also M-tetrapeptide and D-tetrapeptide are signal muropeptides for beta-lactamase induction. In fact, D-tetrapeptide, not D-tripeptide, increases upon imipenem treatment.

A proposed modification of the Wada test for presurgical assessment in temporal lobe epilepsy

We report experience with a modification of the Wada test used before temporal lobe resection in patients with drug-resistant epilepsy. Our procedure consists of injection of amytal via a microcatheter into the anterior choroidal artery or the P2 segment of the posterior cerebral artery and simultaneous presentation of verbal and figural memory test material before, during and after the injection. Pros and cons of the modification and inherent shortcomings of the amytal test are discussed on the basis of the results in ten patients.

Primary structure of cyclohydrolase (Mch) from Methanobacterium thermoautotrophicum (strain Marburg) and functional expression of the mch gene in Escherichia coli

The gene mch encoding N5,N10-methenyltetrahydromethanopterin cyclohydrolase (Mch) in Methano-bacterium thermoautotrophicum (strain Marburg) was cloned and sequenced. The gene, 963 bp, was found to be located at the 3' end of a 3.5-kbp BamHI fragment. Upstream of the mch gene two open reading frames were recognized, one encoding for a 25-kDa protein with sequence similarity to deoxyuridylate hydroxymethylase and the other encoding for a 34.6-kDa protein with sequence similarity to cobalamin-independent methionine synthase (MetE). The N-terminal amino acid sequence deduced for the deoxyuridylate hydroxymethylase was identical to that previously published for thymidylate synthase (TysY) from M. thermoautotrophicum. The 3' end of the tysY gene overlapped by 8 bp with the 5' end of the mch gene. Despite this fact, the mch gene appeared to be transcribed monocistronically as evidenced by Northern blot analysis and primer-extension experiments. The mch gene was overexpressed in Escherichia coli yielding an active enzyme of 37 kDa with a specific activity of 30 U/mg cell extract protein.

[Inhibition of angiogenesis and growth of malignant gliomas in the athymic nude rat model: immunotherapy against "basic fibroblast growth factor"]

An important feature of malignant progression in human gliomas is increased polymorphism of tumor cells associated with karyotypic heterogenity and a variety of secondary changes, one of which is increased angiogenesis. The capability of brain tumors for angiogenesis most probably is the earliest sign for malignancy in 95% of cases and occurs before typical changes of histology appear. Malignant brain tumors are known to produce several angiogenic growth factors. One of the most potent of these factors is the basic fibroblast growth factor (bFGF). In an experimental study human U87 MG glioma cells (2.10(5) cells/50 microliters) were implanted through a burrhole into the cerebral cortex in a group of 25 nude rats. After 3 weeks we found a reproducible extensive tumor growth with extensive neovascularization. Immunohistochemical evaluations proved a high expression of bFGF in the tumor. A parallel group of xenotransplanted rats were treated with 33 micrograms of rabbit anti-bFGF antibodies during tumor cell implantation. Thereafter, the same dosages of antibodies were administrated intracranially twice a week for 3 weeks. We found a significant inhibition of tumor vascularization and growth compared to other groups who had no treatment or who received irrelevant immunoglobulins or saline as a control. Our results indicate that inhibition of tumor angiogenesis might contribute to inhibition of tumor growth in malignant gliomas.

Ultrastructural changes in the blood-brain barrier in rats after treatment with nimodipine and flunarizine. A comparison

The idea of using induced hypertension to treat the symptomatic ischaemia resulting from vasospasm after subarachnoidal hemorrhage, and the effect of this therapy on the blood-brain barrier, is checked in animal experiments. This therapy is combined with the application of nimodipine, which is recognised as the standard medication for prophylaxis of vasospasm. The effects of the induced hypertension combination with Nimodipine and in combination with another calcium antagonist, Flunarizine are compared. Seventy-four narcotised rats, one group with 22 animals treated with Nimodipine and 22 with placebo, and a second group 20 animals treated with Flunarizine and 10 with placebo, are evaluated. The blood pressure is raised to 150-180 mmHg by i.v. application of norfenephrine and measured continuously. The standard tracer, horseradish peroxidase, is applied as indicator for the blood-brain barrier function. 15 minutes later the experimental animals are exsanguinated by perfusion with saline, then perfused with Karnovsky's solution. After removal, the brains are stained for peroxidase to visualise extravasation of the horseradish peroxidase, and after evaluation of the results each brain is assigned to its experimental group. In the Nimodipine group, a significant accumulation (p < 0.001) of perivascular deposits of peroxidase reaction product were found, these were not found in the placebo group. The Flunarizine group does not differ from its placebo group in the number of extravasates, and thus, with respect to protein extravasation, appears better than the Nimodipine group. In electron micrographs of the extravasates one sees intact tight junctions and a neuroendothelial transport, and also vesicles, filled with horseradish peroxidase in the endothelium, the muscle cells, and the brain parenchyma, which arise from pinocytosis. The vesicles, which transport the high-molecular-weight protein, horseradish peroxidase, also transport other proteins and can, therefore, cause a brain edema. It follows from these morphological results that Nimodipine can disrupt the blood brain barrier function and can, therefore, also interfere with cerebral autoregulation, which depends on the resistance of vessels.

In vivo inhibition of angiogenesis and growth of the human U-87 malignant glial tumor by treatment with an antibody against basic fibroblast growth factor

The effectiveness of in vivo suppression of neovascularization and growth of malignant glial tumors by in situ administration of an antibody directed against basic fibroblast growth factor (bFGF), a strong mitogen for cells of mesodermal origin, was tested. One hundred fifty congenitally athymic nude rats (han rnu/rnu) were implanted intracerebrally with U-87MG tumor cells, known constitutive producers of bFGF. The animals were randomly assigned to six groups of 25 animals each. Animals were treated by in situ application of saline (Group F), control antibody (Group D), or polyclonal anti-bFGF antibody (Group B). In additional groups a putative effect on tumor growth caused by the treatment application device itself (between growth control Groups A and E), and the effect of heat-inactivated tumor cells (negative control Group C) were tested. After 3 weeks of treatment, tumor progression and degree of neovascularization were morphometrically recorded. In the untreated Groups A and E massive tumor growth was recorded, consisting of 19.9% +/- 0.4% and 27.1% +/- 0.5%, respectively, of the total brain cross-sectional area. In Group C, no tumor growth occurred. In control Groups D and F tumor progression consisted of 18.6% +/- 0.4% and 18.5% +/- 0.4%, respectively, of the total brain cross-sectional area; whereas in the anti-bFGF treated Group B, significantly smaller tumor masses measuring 7.2% +/- 0.1% were recorded. New blood vessels were located both peritumorally and intratumorally and defined as numerical density and area fraction (number/area and area/area). Significantly more new blood vessels were found in Groups A, D, E, and F, ranging from 41,380/mm2 +/- 464/mm2 to 53,442/mm2 +/- 150/mm2 peritumorally and 51,846/mm2 +/- 495/mm2 to 64,660/mm2 +/- 183/mm2 intratumorally than in the anti-bFGF treated Group B, which numbered 8220/mm2 +/- 225/mm2 peritumorally and 16,554/mm2 +/- 236/mm2 intratumorally. The authors conclude that treatment with anti-bFGF antibody is effective in inhibiting tumor-induced angiogenesis and correlated tumor progression. However, owing to the character of the experimental system used, one cannot exclude the possibility that application of the specific anti-bFGF antibody also counteracts device-induced neovascularization. The authors suggest that combined surgical excision and adjuvant immunotherapy of tumors such as glioblastoma and other malignant brain tumors that express bFGF might prevent tumor recurrence.

Cefotaxime. Unchanged antibacterial activity over years?

During recent years new mechanisms of beta-lactam resistance have developed with the genetic origin on the chromosome or plasmids. Nevertheless, most multicenter studies can demonstrate that cefotaxime has retained its antibacterial activity toward the relevant species. However, it is important to follow the development of resistance closely in hospitals, where epidemic outbreaks of bacterial strains with extended-spectrum beta-lactamases can create difficulties in the treatment of infectious diseases.

[Spinal seeding metastasis of a WHO grade III oligo-astrocytoma]

3 1/2 years after two operations and radiation therapy of a biparietally, parasagittaly localised grade III oligoastrocytoma, a 34-year-old patient developed symptoms of the spinal cord. By performing magnetic resonance tomography and laminectomy, multiple metastases of the anaplastic part of the primary tumour could be identified. Spinal seedings of a tumour of this grading are even rarer than those sporadically reported on corresponding complications of a multiform glioblastoma. Risk factors for the development of such a complication are youth of the patient, primary site of the tumour near the midline and anaplastic parts of the tumour in adults. If such a constellation exists, one should definitely consider the possibility of a spinal seeding in a grade III glioma, especially because in these younger patients thus would be of greater relevance for therapy than in patients with multiform glioblastoma.

[Morphologic characteristics and ATPase activity in permeabilized epididymal bull sperm]

The treatment of bull spermatozoa from epididymal cauda with 5 micrograms digitonin per microliters cells led to the destruction of the plasma membrane which was shown by electron microscopy. Structural changes of mitochondria and of the axoneme were not found. The functional intactness was maintained. The plasma membranes of hypotonically treated spermatozoa were permeable for succinate and the mitochondria showed a diminished functional intactness. For the total ATPase activity of digitonin-treated cells, mainly representing the dynein ATPase, a maximal activity of 20.3 nmol ATP x min-1 x microliters cells-1 (mean +/- S.D.; n = 8) and an apparent half saturation constant of 0.29 mM ATP were determined. The portions of Na(+)-K(+)-ATPase and mitochondrial ATPase in the total ATP-splitting activity were found to be less than 15%. In comparison to the capacity of mitochondrial ATP production, the maximal activity of ATP consuming reactions amounted to about 70%. These results support findings that the ATP turnover of spermatozoa is more limited by the ATP consumption than by the ATP production.

[Multiple meningiomas in different compartments of the cerebrospinal axis]

Multiple meningeomas in the absence of Recklinghausen's disease are rare and usually occur in a single compartment of the neuroaxis. Multiple meningeomas in different neuroaxial compartments are an even rarer condition, only a few cases having been reported. We describe four cases, each with two meningeomas in different compartments of the neuroaxis. Their peculiarity consists in the fact that the different tumours developed at different times and locations in the supratentorial and spinal regions. The radiological and operative findings are described. The possibility of dissemination via the cerebrospinal fluid or blood or of a multifocal origin or genetic predisposition is discussed.

[Initial experiences with a new cerebrospinal fluid collection system]

Due to clinical requirements and to improve the handling of CSF drainage set we developed a new concept, consisting of an arrangement of constructions, which are already available. Besides other advantages, the set provides an ICP monitoring, a pump device and a protection of the air filter of the collecting tank for safer transport. Opening the system for the performance of diagnostic or therapeutic manoeuvres can therefore be avoided. This new equipment has been tested in 28 patients having a ventricular or lumbar CSF drainage with good results and has been quickly accepted by the medical staff. The construction is described in detail.

Grading of supratentorial arteriovenous malformations on the basis of multivariate analysis of prognostic factors

The case histories and angiograms of 93 consecutive patients who underwent surgery for arteriovenous malformations were analyzed retrospectively to find clinical and radiological prognostic factors influencing the outcome. A stepwise multiple regression was performed as follows. All radiological data such as size, location, and feeding and draining vessels as well as the clinical data such as age, sex, clinical grade on admission were introduced into the model and tested whether they contributed significantly to the prediction of the outcome which was the target variable. If so they were retained, otherwise eliminated. By this procedure the following features were identified as significant prognostic factors which adversely influence the outcome: poor clinical grade, feeding vessels from the A 1-segment and the anterior communicating artery, feeders from the M 1-segment, feeders from the Rolandic branches of the middle cerebral artery, a shunt through the anterior communicating artery. Neither the presence of a particular draining vein nor the type of the venous drainage when divided into superficial or deep had an influence on the outcome. Nor was the size of the lesion of significant importance. The bearing of these findings on the value of established grading systems is discussed and a new grading system is proposed.

Combined orbito-frontal, sub- and infratemporal fossa approach to skull base neoplasms. Surgical technique and clinical application

Neoplasms located along the antero-lateral skull base, with probable involvement of the orbit and with extension into the pterygoid and/or infratemporal fossa can usually not be sufficiently exposed using standard neurosurgical or otosurgical approaches, which is why combined approaches to these skull base targets have been developed in the recent past. In this report we describe our experience, using a combined orbito-frontal, sub- and infratemporal fossa approach which, starting with a pre-auricular incision and a standard pterional craniotomy, is extended to an extensive osteoplastic enbloc resection of the orbito-zygomatic area allowing for direct visualisation of the antero-temporo-lateral skull base from the orbital cavity to the depth of the infratemporal and pterygoid fossa. The surgical technique as well as the clinical experiences accumulated with this approach are described.

Subacute hydrocephalus after experimental subarachnoid hemorrhage: its prevention by intrathecal fibrinolysis with recombinant tissue plasminogen activator

It is investigated whether intrathecal fibrinolysis may prevent subacute hydrocephalus after subarachnoid hemorrhage (SAH). In 19 cats, SAH was induced by the intracisternal infusion of 1 ml/kg body weight of fresh autologous blood at a rate of 0.6 ml/min. Eleven of those animals were treated by intrathecal fibrinolysis performed 24 hours after experimental SAH by intracisternal infusion of 3 mg of recombinant tissue plasminogen activator. Included were eight animals suffering from experimental SAH and four healthy animals retained for control. A computed tomographic scan performed 24 hours after the SAH displayed an acute hydrocephalus from the experimental procedure. Cerebrospinal fluid outflow resistance was 71 +/- 5.0 mm Hg/ml/min in the healthy animals, 265 +/- 19.8 mm Hg/ml/min in the nontreated animals 7 days after SAH, and 151 +/- 6.4 mm Hg/ml/min in the recombinant tissue plasminogen activator-treated animals 7 days after SAH (mean +/- standard deviation; changes significant with P less than 0.01). Postmortem planimetry of both lateral ventricles gives a mean of 3.7 +/- 2.7 mm2 in the healthy animals, 11.1 +/- 3.9 mm2 in the nontreated group after SAH (P less than 0.01), and 3.5 +/- 1.1 mm2 in the animals treated with recombinant tissue plasminogen activator. Intracranial pressure monitoring demonstrated marked intracranial pressure waves only in the nontreated animals after SAH. It is concluded that intrathecal fibrinolysis may prevent subacute hydrocephalus after experimental SAH.

The results of surgery for intracerebral hematomas

Our retrospective study included 104 patients (28 female and 76 male) with intracerebral bleeding, treated between 1978 and 1988 in the Neurosurgical Clinic of the Medical University in Hannover. The average age was 43 years. 53 patients presented with traumatic intracerebral bleedings, and 51 with spontaneous hematomas. 31 patients with spontaneous hematomas were operated: among these a good or satisfactory result was obtained in 19 patients, and 12 died. Of the 20 non-operated patients, a good or satisfactory result was achieved in 10. 31 patients were operated in the group with traumatic hematoma, of these 22 had a good or satisfactory outcome and 9 patients died or had an unsatisfactory result. Of the 22 non-operated patients, 13 died and 9 achieved a good or satisfactory result. In the stratified Chi2-Test the effects of the operation were not found to be significant, with 0.1 less than p less than 0.25 for spontaneous, and 0.25 less than p less than 0.05 for the traumatic hematomas. There is a trend in favor of the operation in certain cases.

Cerebral blood flow and intracranial pressure during experimental subarachnoid haemorrhage

The relationships of intracranial pressure (ICP), systemic blood pressure (SBP) and cerebral blood flow (CBF) during experimental subarachnoid haemorrhage were investigated in cats. Continuous monitoring of regional cerebral blood flow (rCBF) was done by a thermal diffusion method using a Peltier stack. During haemorrhage ICP rose within 5.4 +/- 0.97 minutes from 10.5 +/- 4.9 to 176.1 +/- 27.8 mmHg. This strong increase of ICP resulted in a temporary arrest of cerebral circulation. The Cushing response during the haemorrhage could not improve the cerebral circulation, but in contrast caused a further increase of ICP. After the haemorrhage the cerebral blood flow normalised within minutes. It is concluded, that the Cushing response during a subarachnoid haemorrhage should be regarded as a deleterious rather than a beneficial mechanism.

Ultrastructural changes in the blood-brain barrier after nimodipine treatment and induced hypertension

Fourty-four narcotized rats were split into two equal groups, one being treated with nimodipine and the other with a placebo. By use of norfenefrine the blood pressure was raised to values of 150 and 180 mm Hg within the limits of the autoregulation of brain perfusion and under continuous measurement. Fifteen minutes after application of the standard tracer, horseradish peroxidase, the animals were exsanguinated using a saline perfusion and then perfusion-fixed with Karnovsky's solution. After development of the peroxidase staining the brain sections were evaluated and then allocated to their respective groups. In brain tissues from the experimental group significantly more frequent perivascular accumulations of horseradish peroxidase reaction product were found (P less than 0.001). In electron micrographs it could be seen that the tight junctions were intact and that there was a neuroendothelial transport, with horseradish peroxidase-filled vesicles, in the endothelium, muscle cells, and brain parenchyma. These vesicles represent a medium of transport for all proteins of high molecular weight and can therefore result in brain edema. It is concluded that nimodipine damages the blood-brain barrier by disturbance of the autoregulation of the cerebral blood flow.

Effects of 33% stable xenon/O2 mixture on somatosensory evoked potentials

The influences of 30% stable xenon/O2 mixture on somatosensory evoked potentials were investigated in 8 patients with and without Diamox application. Changes of the amplitude of the primary cortical response occurred frequently and correlated well with the psychotropical effect of xenon. They usually normalized within 2 to 3 minutes after ending xenon inhalation. There were no significant changes of the latency of the N20.

Influence of type and extent of surgery on early results and survival time in glioblastoma multiforme

We studied the influence of the type of surgery (microsurgery or macrosurgery) and extent (complete resection with lobectomy, complete resection alone, partial resection with lobectomy or partial resection alone) on early postoperative results and survival time in 118 consecutive patients who underwent surgery for glioblastoma multiforme. Early results were assessed by the Karnofsky score at 4 weeks postoperatively. Survival was compared using Kaplan-Meier curves and Mantel statistics. The median survival time (MST) after microsurgery (12.1 months) was significantly longer than that after macrosurgery (7.3 months). The longer survival after microsurgery was, however, largely attributable to better early results and a consequently higher proportion of patients who could undergo radiotherapy. Complete resection was superior to partial resection. Additional lobectomy did not appreciably influence the early results and the MST in completely resected tumours. So the MST after complete resection in the microsurgical group without lobectomy was 12.6 months, with lobectomy 12.9 months. In the macrosurgical group the respective values were 7.4 months without and 8.2 months with lobectomy. In incompletely resected tumours lobectomy worsened the early results compared to incomplete resection alone and led to a shorter MST.