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Due to their infiltrative growth behavior, gliomas have, even after surgical resection, a high recurrence tendency. The approach of intracavitary radioimmunotherapy (RIT) is aimed at inhibiting tumor re-growth by directly administering drugs into the resection cavity (RC). Direct application of the radioconjugate into the RC has the advantage of bypassing the blood-brain barrier, which allows the administration of higher radiation doses than systemic application. Carbonic anhydrase XII (CA XII) is highly expressed on glioma cells while being absent from normal brain and thus an attractive target molecule for RIT. We evaluated a CA XII-specific 6A10 Fab (fragment antigen binding) labelled with6A10 Fab fragment was modified and radiolabelled withThe in vitro CA XII binding capacity of the modified Fab was confirmed. Radiochemical purity was determined to be90% after 72 h of incubation under physiological conditions. Autoradiography experiments proved the specific binding of the Fab to CA XII on tumor cells. Biodistribution studies revealed a tumor uptake of 3.0%ID/g after 6 h and no detectable brain uptake. The tumor-to-contralateral ratio of 10/1 was confirmed by quantitative planar scintigraphy.The radiochemical stability in combination with a successful in vivo tumor uptake shows the potential suitability for future RIT applications with the 6A10 Fab.

Summary Aim: None of the established treatments (surgery, radiotherapy, chemotherapy) for malignant glioma has improved its very poor prognosis. Adjuvant locoregional radioimmunotherapy (RIT) represents a new therapeutic approach. We present our initial experience with this therapeutic tool with respect to adverse effects, biokinetics and clinical follow-up. Methods: Following surgery and radiotherapy, 12 patients with glioma (4, WHO stage III; 8, WHO stage IV) underwent 1-5 RIT-cycles (average dose 1100 MBq 131labelled monoclonal BC-4 antibodies) at six week intervals. Follow-up included serial FDG-PET and MRI investigations. Evaluation of biokinetics included whole body scans, together with analysis of blood, urine and fluid from the tumor cavity. Results: Following RIT, four patients experienced temporary seizures, which, in one case, were associated with temporary aphasia. Eight patients developed HAMA (human anti-mouse antibodies) during follow-up. Mean biologic half-life of the radiopharmaceutical in the resection cavity was 3.9 d (range: 1.0-10.2 d) and remained stable intraindividually during further RIT-cycles. The antibody/radionuclide conjugate remained stable in the tumor cavity for at least 5 d. Median survival presently stands at 18.5 months compared to 9.7 months in a historical patient group (n = 89) undergoing conventional therapeutic strategies. Five patients show no signs of recurrence. In three patients with post-surgical evidence of residual tumor, one patient showed partial remission, one stable disease, and one progressive disease during RIT. Four patients without evidence of residual tumor mass at the beginning of RIT developed recurrence during therapy. Conclusions: Initial experience demonstrates that locoregional RIT is a well tolerated treatment modality that may represent a promising new approach in the management of patients with malignant glioma. Advantages of local application include passage of the blood-brain barrier, high concentration of activity within the resection cavity and low systemic toxicity.

In einer halb retro- und halb prospektiven multizentrischen Studie in der Region Munchen im Jahre 1992 wurden 80% von 104 Patienten mit schwerem SHT von einem Notarzt am Unfallort versorgt. Die mittlere Eintreffzeit betrug 8,2 Minuten. 70% der Patienten wurden direkt vom Unfallort in ein Zentrum mit neurochirurgischer Fachabteilung transportiert, weit mehr als die Halfte hiervon innerhalb der ersten Stunde. Die Dokumentation der Versorgung durch den Notarzt zeigte erhebliche Mangel. Aus den vorhandenen Daten geht aber hervor, das im Vergleich zu fruheren Arbeiten ein Trend zur haufigeren Intubation am Unfallort durch Notarzte zu verzeichnen ist. Insgesamt last sich, von wenigen Ausnahmen abgesehen, ein hoher Standard in der praklinischen Versorgung (schnelles Eingreifen, fruhzeitige aggressive Kreislauf- und Atemstabilisierung) verzeichnen. Weitere Studien sind nun notwendig, die Effizienz dieser praklinischen Versorgung fur das Outcome von Patienten mit SHT naher zu untersuchen.

72 patients with isthmic spondylolisthesis have been analyzed prospectively with respect to their clinical presentation, radiological and intraoperative findings, operative techniques and surgical results. Excellent, good and satisfactory results have been obtained in 59 (82%), 10 (14%) and 3 patients (4%), respectively, by use of microsurgical techniques in combination with Louis-plate-fixation in Grade I and double arthrodesis/Cotrel-Dubousset-instrumentation in Grade II spondylolisthesis.

It is strongly recommended that general guidelines and internal regulations be laid down in written form by the department. The guidelines regulate the general workflow and related trainee duties and responsibilities, education and research, special procedures for particular diseases and conditions (standards of care). Regarding general workflow of the department, the following items should be laid down once in written form: time table of department, working hours, admission procedures, medical records directives, responsibilities on wards and in the emergency unit, patient information, discharge procedures, outpatient consultations, call schedule and on-call duty plan, as well as week-end and holiday regulations for rounds on wards and ICU. Regarding education and research, the following items should be written down: conferences and teaching rounds, policies on presentations and publications, policies regarding meetings and courses, research leave and vacation plan. The written definition of standards of care is still considered optional in neurosurgery at the present time.

Treatment of patients suffering from severe head injury is so far restricted to general procedures, whereas specific pharmacological agents of neuroprotection including hypothermia have not been found to improve the outcome in clinical trials. Albeit effective, symptomatic measures of the preclinical rescue of patients (i.e. stabilization or reestablishment of the circulatory and respiratory system) or of the early clinical care (e.g. prompt diagnosis and treatment of an intracranial space occupying mass, maintenance of a competent circulatory and respiratory system, and others) by and large constitute the current treatment based on considerable organizational and logistical efforts. These and other components of the head injury treatment are certainly worthwhile of a systematic analysis as to their efficacy or remaining deficiencies, respectively. Deficits could be associated with delays of providing preclinical rescue procedures (e.g. until intubation of the patient or administration of fluid). Delays could also be associated in the hospital with the diagnostic establishment of intracranial lesions requiring prompt neurosurgical intervention. By support of the Federal Ministry of Education and Research and under the auspices of the Forschungsverbund Neurotraumatology, University of Munich, a prospective system analysis was carried out on major aspects of the pre- and early clinical management at a population based level in patients with traumatic brain injury. Documentation of pertinent data was made from August 1998 to July 1999 covering a catchment area of Southern Bavaria (5.6 mio inhabitants). Altogether 528 cases identified to suffer from severe head injury (GCSor = 8 or deteriorating to that level within 48 hrs) were enrolled following admission to the hospital and establishment of the diagnosis. Further, patients dying on the scene or during transport to the hospital were also documented, particularly as to the frequency of severe head injury as underlying cause of mortality. The analysis included also cases with additional peripheral trauma (polytrauma). The efficacy of the logistics and organization of the management was studied by documentation of prognosis-relevant time intervals, as for example until arrival of the rescue squad at the scene of an accident, until intubation and administration of fluid, or upon hospital admission until establishment of the CT-diagnosis and commencement of surgery or transfer to the intensive care unit, respectively. The severity of cases studied in the present analysis is evident from a mortality of far above 40% of cases admitted to the hospital, which was increased by about 20% when including prehospital mortality. The outcome data notwithstanding, the emerging results demonstrate a high efficacy of the pre- and early clinical management, as indicated by a prompt arrival of the rescue squad at the scene, a competent prehospital and early clinical management and care, indicative of a low rate of avoidable complications. It is tentatively concluded on the basis of these findings that the patient prognosis is increasingly determined by the manifestations of primary brain damage vs. the development of secondary complications.

Treatment of patients suffering from severe head injury is so far restricted to general procedures, whereas specific pharmacological agents of neuroprotection including hypothermia have not been found to improve the outcome in clinical trials. Albeit effective, symptomatic measures of the preclinical rescue of patients (i.e. stabilization or reestablishment of the circulatory and respiratory system) or of the early clinical care (e.g. prompt diagnosis and treatment of an intracranial space occupying mass, maintenance of a competent circulatory and respiratory system, and others) by and large constitute the current treatment based on considerable organizational and logistical efforts. These and other components of the head injury treatment are certainly worthwhile of a systematic analysis as to their efficacy or remaining deficiencies, respectively. Deficits could be associated with delays of providing preclinical rescue procedures (e.g. until intubation of the patient or administration of fluid). Delays could also be associated in the hospital with the diagnostic establishment of intracranial lesions requiring prompt neurosurgical intervention. By support of the Federal Ministry of Education and Research and under the auspices of the Forschungsverbund Neurotraumatology, University of Munich, a prospective system analysis was carried out on major aspects of the pre- and early clinical management at a population based level in patients with traumatic brain injury. Documentation of pertinent data was made from August 1998 to July 1999 covering a catchment area of Southern Bavaria (5.6 mio inhabitants). Altogether 528 cases identified to suffer from severe head injury (GCS < or = 8 or deteriorating to that level within 48 hrs) were enrolled following admission to the hospital and establishment of the diagnosis. Further, patients dying on the scene or during transport to the hospital were also documented, particularly as to the frequency of severe head injury as underlying cause of mortality. The analysis included also cases with additional peripheral trauma (polytrauma). The efficacy of the logistics and organization of the management was studied by documentation of prognosis-relevant time intervals, as for example until arrival of the rescue squad at the scene of an accident, until intubation and administration of fluid, or upon hospital admission until establishment of the CT-diagnosis and commencement of surgery or transfer to the intensive care unit, respectively. The severity of cases studied in the present analysis is evident from a mortality of far above 40% of cases admitted to the hospital, which was increased by about 20% when including prehospital mortality. The outcome data notwithstanding, the emerging results demonstrate a high efficacy of the pre- and early clinical management, as indicated by a prompt arrival of the rescue squad at the scene, a competent prehospital and early clinical management and care, indicative of a low rate of avoidable complications. It is tentatively concluded on the basis of these findings that the patient prognosis is increasingly determined by the manifestations of primary brain damage vs. the development of secondary complications.

Radical resections of contrast-enhancing tumour in patients with malignant gliomas may be pertinent for survival but are often difficult to achieve due to uncertainties in distinguishing tumour margins intra-operatively. In this respect a number of novel methods are being examined which aim at enhancing resections. Among these methods, resections that exploit the accumulation of fluorescent porphyrins within malignant glioma tissue in response to exogenous administration of a metabolic percursor, 5-aminolevulinic acid, may offer particular advantages. This article summarises the clinical background and current status of 5-ALA drug development for fluorescence-guided resections of malignant gliomas and analyses the available literature with regard to possible mechanisms that govern the highly specific accumulation of fluorescent porphyrins in malignant glioma tissue in response to 5-ALA administration.

In the last two decades radioimmunotherapy has been used as an additional treatment option for malignant glioma in several centers. More than 400 patients have been reported, who were treated in the framework of different studies. Most of them received labelled antibodies to tenascin, an extracellular matrix-glycoprotein, which is expressed in high amounts in malignant gliomas. We report side effects and survival time of 46 patients, treated after surgical resection and conventional radiotherapy with intralesionally injected labelled (131-Iodine) antibodies to tenascin. Despite the fact, that many treatments have been performed, little is known about the distribution properties of labelled antibodies after injection in the tumour cavity. For an optimal effect labelled antibodies should be able to reach tumour cells, which have migrated into the surrounding tissue. We investigated the propagation velocity and area of distribution of labelled antibodies and their considerably smaller fragments after the injection in C6-gliomas of Wistar rats. Propagation increased with time and was significantly greater after injection of labelled fragments than after injection of labelled antibodies. According to our results labelled fragments might be better able to reach distant tumour cells in the peritumoural tissue of malignant gliomas than labelled antibodies.

Prognosis of malignant glioma is very unfavourable mainly due to minimal tumour remnants in the peritumoural tissue. Intralesionally applied radioimmunotherapy is a possible therapeutical option with the potential to improve survival of patients with malignant glioma. We investigated side effects and survival after surgery, conventional radiotherapy and additional radioimmunotherapy with labelled tenascin-antibodies in patients with malignant glioma.Since 1995, 37 patients were treated with radioimmunotherapy after resection and radiotherapy of a malignant glioma. Patients received antibodies labelled with yttrium-90 and iodine-131 in different doses into the tumour cavity via a previously implanted ommaya-reservoir. Treatment was applied in up to 8 cycles (mean 2.96 cycles) in time intervals of 6-8 weeks. Mean age was 46 years, histology was anaplastic astrocytoma in 13 patients and glioblastoma in 24 patients.For the whole group median survival time has not yet been reached. For glioblastoma the median survival time is 17 months, 5-year survival probability for anaplastic astrocytoma is 85% approximately. Quality of life was acceptable. Acute side effects following treatment were headache, seizures and worsening of pre-existing neurological symptoms. Late side effects were skin necrosis and, in 1 case, a delayed aphasia probably due to a vascular lesion.Radioimmunotherapy prolonged survival time in a selected group of patients with malignant gliomas as compared to a historical control group. Patients with anaplastic astrocytomas seem to have more benefit from this therapy than patients with glioblastomas.

Research rotation is an important component in the education of a neurosurgical resident. The selection of the area of research is essential. There are many arguments in favour of selecting research projects to be close to the individual trainee's clinical interest. Studies far away from the individual's clinical interest in most cases are less productive and will not be pursued later. There are also many advantages if a cooperation is planned with other institutions. The programme director or staff members play an important role in the selection of the research project, of an appropriate laboratory or institution, and in the process of financing a research rotation.

None of the established treatments (surgery, radiotherapy, chemotherapy) for malignant glioma has improved its very poor prognosis. Adjuvant locoregional radio-immunotherapy (RIT) represents a new therapeutic approach. We present our initial experience with this therapeutic tool with respect to adverse effects, biokinetics and clinical follow-up.Following surgery and radiotherapy, 12 patients with glioma (4, WHO stage III; 8, WHO stage IV) underwent 1-5 RIT-cycles (average dose 1100 MBq 131labelled monoclonal BC-4 antibodies) at six week intervals. Follow-up included serial FDG-PET and MRI investigations. Evaluation of biokinetics included whole body scans, together with analysis of blood, urine and fluid from the tumor cavity.Following RIT, four patients experienced temporary seizures, which, in one case, were associated with temporary aphasia. Eight patients developed HAMA (human anti-mouse antibodies) during follow-up. Mean biologic half-life of the radiopharmaceutical in the resection cavity was 3.9 d (range: 1.0-10.2 d) and remained stable intraindividually during further RIT-cycles. The antibody/radionuclide conjugate remained stable in the tumor cavity for at least 5 d. Median survival presently stands at 18.5 months compared to 9.7 months in a historical patient group (n = 89) undergoing conventional therapeutic strategies. Five patients show no signs of recurrence. In three patients with post-surgical evidence of residual tumor, one patient showed partial remission, one stable disease, and one progressive disease during RIT. Four patients without evidence of residual tumor mass at the beginning of RIT developed recurrence during therapy.Initial experience demonstrates that locoregional RIT is a well tolerated treatment modality that may represent a promising new approach in the management of patients with malignant glioma. Advantages of local application include passage of the blood-brain barrier, high concentration of activity within the resection cavity and low systemic toxicity.

The periodic evaluation of the progress made by the trainees is an adequate means for quality control of a training programme. The combination of the Neurosurgical Log-book and the new Evaluation Sheet allows a comprehensive assessment of the knowledge, progress, as well as the personal and professional development of the individual resident. Upcoming problems can be recognised at an early time point and be corrected immediately. With such periodic supervision the quality of training will improve with time and with experience.

Aim of the current study was to investigate the influence of intracranial hypertension on the resolution of vasogenic brain edema following intracerebral hemorrhage. An intracerebral hematoma was induced by 500 microliters of blood injected into the left frontal lobe of rabbits (n = 25). Na(+)-fluorescein (MW376) and Texas-Red-albumin (MW67.000) were administered intravenously as edema markers. By using a closed cranial window for superfusion of the brain surface and a ventriculo-cisternal perfusion the clearance of both fluorescence markers was measured in the CSF-effluates up to 8 hours using spectrophotometry. ICP was adjusted between 2-6 mmHg (low pressure, n = 10), 8-12 mmHg (moderate pressure, n = 10) or 14-20 mmHg (high pressure, n = 5). In all groups Na(+)-fluorescein started to accumulate at 60 min after induction of the hematoma in the subarachnoid space, while at 90 min in the ventricular system. In the low intracranial pressure group Na(+)-fluorescein (mean +/- SEM) in the ventricular system amounted to 1.47 +/- 0.42 nmol as compared to 1.34 +/- 0.41 nmol in the moderate, or 0.38 +/- 0.11 nmol in the high intracranial pressure group. In the subarachnoid space the marker reached 1.96 +/- 0.57 nmol, 4.15 +/- 1.28 nmol, or 0.96 +/- 0.32 nmol, respectively. In conclusion, the data demonstrate that vasogenic edema induced by an intracerebral hematoma is cleared into both CSF compartments, albeit with delay into the ventricular system. Edema resorption occurred earlier and to a higher extent into the subarachnoid space as compared to the ventricular system. Further, edema resorption is influenced by the actual intracranial pressure, with marked inhibition by a high intracranial pressure.

Normal pressure hydrocephalus (NPH), which may either be idiopathic or occur secondarily, is responsible for approximately 6% of the cases of dementional syndromes in the elderly. Although its diagnosis still remains a problem, every attempt should be made to identify patients with clinical symptoms arising from NPH, since the placement of a shunt can result in a much improved quality of life. Candidates for surgical treatment must be selected with care, since the transient peri-operative morbidity may be as high as 7%.

After adoptive transfer of pre-activated lymphocytes into the operation cavity of glioma patients, tumor regression and improved survival have been reported in some patients. Results were most impressive when bispecific antibodies with tumor x CD3 specificity were also applied. In this study, we attempted to avoid time-consuming pre-activation procedures for adoptively transferred cells by using a combination of bispecific antibodies directed to the EGF receptor (EGFR) on tumor cells and to CD3 and CD28 on T cells. Eleven patients with high-grade malignant glioma received 3 injections of 2 bispecific antibody fragments (EGFR x CD3 and EGFR x CD28) together with freshly isolated autologous lymphocytes via an Ommaya reservoir. Intracavitary fluid aspirated during immunotherapy was examined for markers of T-cell activation. Increased levels of soluble IL-2 receptor and TNF-alpha were detected in the intracavitary fluid of all patients tested. Two of the 11 treated patients experienced a beneficial response to therapy as defined by a transient contrast enhancement in subsequent MRI scans and prolonged survival. Side effects were transient and consisted of fever, nausea, headache and aggravation of pre-existing neurologic deficits. These adverse effects were most likely due to the antibody construct containing anti-CD3 specificity. Two patients developed cerebral edema and required steroid treatment.

For several years lasers have been used routinely in percutaneous nucleotomy. However, there still is very little standardized data on the effect of specific laser parameters on the ablation rate of spinal disc tissue. The aim of our study was to quantify the effects of the Ho:YAG and Nd:YAG lasers on disc tissue ablation, by systematically changing specific energy parameters, to determine the optimal parameter combination for tissue ablation.

In October 1997, after a preparatory phase of 8 years, the first patient in Europe was treated by BNCT at the High Flux Reactor (HFR) of the European Commission in Petten, The Netherlands.1 The preparation for the first clinical BNCT trial in Europe included comprehensive scientific experimental and human investigations with the boron compound borocaptate sodium (BSH).2,3 A multitude of open legal and administrative questions had to be overcome. Furthermore a complex structure had to be organized and the procedures had to be defined how to perform a multi-national, multi-institutional study using a nuclear reactor distant from hospital for patient treatment performed by an international team on a multidisciplinary base.4 The international standards of clinical research as well as the accepted rules and definitions of conventional radiotherapy were applied, involving independent experts in order to assure the quality of the study and the quality of the Performance of patient treatment. The goal was to execute the project to a very high Standard as would be expected in the leading radiotherapy depart-ments in Europe.5

Temporary occlusion of cerebral arteries is a common technique to facilitate neurovascular surgery, however, it puts the patient at risk of permanent deficits caused by focal ischemia. Currently, the gold standard of cerebroprotection is barbiturate-induced burst suppression. In addition, the neurosurgical standard drug therapy involves nimodipine, mannitol, and dexamethasone. We have recently demonstrated the superior neuroprotective efficacy of combination therapy with magnesium (calcium- and glutamate-antagonist) + tirilazad (antioxidant) + mild hypothermia (33°C). In the present study we compared this pathophysiologi- cally orientated treatment strategy with the standard regimen. Furthermore, we investigated whether barbiturates provide an additional neuroprotective effect under hypothermic conditions. 142 Sprague-Dawley rats were subjected to 90 min of middle cerebral artery (MCA) occlusion by an intraluminal filament technique, and randomly assigned to the following groups. In part I of the study each drug of the standard regimen was evaluated as monotherapy and in combination. In part II of the study the most effective standard therapy (nimodipine + mannitol + dexamethasone + burst suppression by methohexital) was compared with magnesium + tirilazad + mild hypothermia (33°C). In part III of the study, burst suppression by methohexital and mild hypothermia were evaluated as monotherapy and in combination. Local cortical blood flow was measured by continuous laser Doppler flowmetry. Neurological examinations were performed daily, and infarct size was histologically assessed after 7 days. Part I: Standard drugs alone or in combination moderately limited infarct volume, with mannitol and burst suppression by methohexital being the most effective monotherapies (33% reduction of infarct volume). Most of the animals had residual neurological deficits at the end of the observation period. Part II: Again, combination therapy with standard drugs + burst suppression only moderately limited infarct volume by 36%. In contrast, combination therapy with magnesium + tirilazad + mild hypothermia abolished cortical infarction and reduced total infarct volume by 73% (P

It has been established that 5-aminolevulinic acid (5-ALA) induces the accumulation of fluorescent porphyrins in glioblastoma multiforme (GBM), a phenomenon potentially exploitable to guide tumor resection. In this study the authors analyze the influence of fluorescence-guided resection on postoperative magnetic resonance (MR) imaging and survival in a series of patients who underwent surgery in the authors' department.Fifty-two consecutive patients with GBM received oral doses of 5-ALA (20 mg/kg body weight) 3 hours before induction of anesthesia. Intraoperatively, tumor fluorescence was visualized using a modified operating microscope. Fluorescing tissue was removed whenever it was considered safely possible. Residual enhancement on early postoperative MR imaging was quantified and related to each patient's characteristics to determine which factors influenced resection. Survival was analyzed using the Kaplan-Meier method and multivariate analysis was performed in which the Karnofsky Performance Scale (KPS) score, residual fluorescence, patient age, and residual enhancement on MR images were considered. Intraoperatively, two fluorescence qualities were perceived: solid fluorescence generally reflected coalescent tumor, whereas vague fluorescence mostly corresponded to infiltrative tumor. Complete resection of contrast-enhancing tumor was accomplished in 33 patients (63%). Residual intraoperative tissue fluorescence left unresected for safety reasons predicted residual enhancement on MR images in 18 of the 19 remaining patients. Age, residual solid fluorescence, and absence of contrast enhancement in MR imaging were independent explanatory factors for survival, whereas the KPS score was significant only in univariate analysis. No perioperative deaths and one case of permanent morbidity were encountered.The observations in this study indicate the usefulness of 5-ALA-induced tumor fluorescence for guiding tumor resection. The completeness of resection, as determined intraoperatively from residual tissue fluorescence, was related to postoperative MR imaging findings and to survival in patients suffering from GBM.

Investigations of the mechanisms of cerebral ischemia have revealed that cell death is mediated, among other things, by a massive release of excitatory amino acids [9], generation of free radicals [50] and, as a final step, calcium influx into cells [49]. This understanding has led to a search for pharmacologic agents that protect the brain against these mechanisms. Although the molecular processes of the postischemic events are still only partially understood, numerous experimental neuroprotective drugs have been developed. Many of them are currently under clinical evaluation for the treatment of ischemic stroke, subarachnoid hemorrhage (SAH), or head injury. Yet, encouraging results from clinical trials are still rare. No trial has shown any single agent to be effective so far [57]. As a multitude of mechanisms is involved in ischemic brain injury, it is conceivable that a single pharmacotherapeutic agent aimed at just one process of ischemic damage is unlikely to be sufficient, and that a combination of treatment procedures would be more promising.

Neuronal death after cerebral ischemia is mediated by a massive release of excitatory amino acids and generation of free radicals. Calcium influx into cells is considered to be a crucial step of the deleterious cascade triggered by ischemia. Magnesium competes with calcium to reduce calcium entry into cells, blocks voltage-sensitive and N-methyl-d-aspartate-activated ion channels, and inhibits the release of excitatory amino acids. The 21-amino steroid tirilazad is a well-known antioxidant. We speculated that combined administration of these clinically available drugs might be superior to current monotherapy.

Resolution of vasogenic brain edema was examined using the infusion edema model in rabbits. Texas Red-albumin (MW 66,000 D) and sodium fluorescein (MW 376 D) dissolved in artificial cerebrospinal fluid (aCSF) were infused into the white matter of the left frontal lobe of the brain. To quantify the edema fluid cleared by the ventricular system, ventriculo-cisternal perfusion was performed with aCSF. A closed cranial window, implanted above the left parietal brain, served for studying resolution of the artificial edema fluid via the subarachnoid space. CSF-samples were collected in 30 minutes-intervals and analysed with a spectrophotometer. Clearance of edema fluid was examined under low (2-5 mm Hg), medium (9-12 mm Hg), or high (14-17 mm Hg) intracranial pressures (ICP). In the low pressure-group, both edema fluid markers were found in the ventriculo-cisternal and subarachnoid perfusate at 60 and 90 min, in the group with moderately increased ICP at 90 and 120 min, respectively. In the high ICP-group both fluorescence dyes appeared not less than 90 min in the ventricular system, while no increase at all could be found in the subarachnoid space. Our results imply that resolution of edema fluid via both the ventricular system and the subarachnoid space depends on the actual ICP level.

We report on 30 cases where we have used cortical stimulation mapping to define the areas representing sensorimotor, language and speech functions under local anesthesia to facilitate resection of space-occupying lesions near these areas. Under the simplistic concept that Broca's area lies in the frontal operculum (inferior frontal gyrus) and that Wernicke's area is located in the posterior perisylvian area (superior temporal, angular and supramarginal gyri), we found language and speech function to be represented outside these areas in up to 4 stimulation sites of 15 patients. The results of cortical stimulation mapping were therefore essential to decide on the optimal access route to the lesions that were located subcortically and on the optimal resection plane in gliomas. After the limits of these areas and of the lesions had been established with stimulation mapping and with intrasurgical microscopic smear preparations, respectively, lesions were safely removed under continuous monitoring of sensorimotor, language and speech function. Immediately after surgery we encountered language and speech deficits in 9 patients (30%), which resolved completely in 5 and incompletely in 4 instances. Thus, language functions were normal in 26 patients (87%) at the end of the follow-up period. It is concluded that use of this technique allows safe and extensive resection of lesions that would otherwise have been considered hazardous to remove or inexcisable.

Um den Einflus der verschiedenen Laserparameter auf die Abtragung von Bandscheibengewebe zu untersuchen, wurden bei einem Holmium:YAG-Laser (λ=2130 nm) die Energie eines Einzelimpulses, die Gesamtenergie und die Repetitionsrate systematisch verandert um deren Einflus auf die Grose der Ablation und die Verkohlung des Bandscheibengewebes zu bestimmen. Alle Untersuchungen wurden im contact-mode, unter Beruhrung des Lichtwellenleiters mit der Bandscheibenoberflache, und im non-contact-mode, einem Abstand zwischen dem Lichtwellenleiter und der Oberflache der Bandscheibe von 1 mm, durchgefuhrt.