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W J Bock

Publications and source records attributed to W J Bock.

At least 19 recordsLinked to original sources
PubMed1998

Combined therapy of medulloblastoma: review of 46 patients treated in a single institution.

Medulloblastoma is the most frequent malignant brain tumor in pediatric patients. Early treatment strategies, combining surgery and radiotherapy alone, resulted in survival rates of about 40% only. In the last 15 years, chemotherapy was used more frequently in combination with surgery and radiotherapy. The rationale was to increase the survival rate and to decrease radiation toxicity in young children. Forty-six patients younger than 16 years were treated between July 1977 and September 1995 in our institution (32 boys and 14 girls). Thirty-nine patients could be evaluated according to their postoperative treatment with regard to different protocols such as SIOP 1, SIOP 2, HDMTX/VCR, HIT protocol 89/91 and Carbo-PEI (one patient). In total, 21/39 patients are alive without evidence of disease (EFS 55 +/- 7%) with a follow-up of 26 to 210 months. Four children are lost to follow-up. Twelve patients died after relapse, 1 child died of MTX-induced brain atrophy, 1 patient developed a secondary malignancy (acute lymphoblastic leukemia) and died. The best results were seen in patients treated according to the HIT 89/91 protocol as first-line treatment (CR 9/10). The improvement in outcome of our patients with medulloblastoma in recent years suggests the benefit of intensified chemotherapy on survival. In addition, refinement in surgical and radiological treatment have certainly also contributed to the better results.

Adolescent↗
PubMed1997

3-[123I]iodo-alpha-methyltyrosine and [methyl-11C]-L-methionine uptake in cerebral gliomas: a comparative study using SPECT and PET.

UNLABELLED: This study compares the uptake of the nonmetabolizable amino acid analog 3-[123I]iodo-alpha-methyltyrosine (IMT) and of [methyl-11C]-L-methionine (MET) in cerebral gliomas. METHODS: In 14 patients with cerebral gliomas, IMT uptake was measured using SPECT (10 dynamic, 4 static SPECT acquisitions) and, on the same day, MET uptake by dynamic PET. The IMT and MET data were compared with respect to tracer kinetics, tumor to brain ratios (T/B) and tumor size after converting the resolution of the PET scans to that of the SPECT scans (14 mm FWHM). RESULTS: All gliomas showed increased uptake of both tracers in relation to normal brain tissue. Visual comparison of the scans yielded no differences in tumor size and shape with both methods. IMT showed a maximal tracer uptake in brain and in tumors at about 15 min postinjection which was followed by a washout of 45.0% +/- 13.5% in gliomas (mean +/- s.d., p < 0.001, n = 10) and 35.3% +/- 5.4% in normal brain (p < 0.001, n = 10) at 60 min postinjection. MET concentration in tumor tissue or brain tissue between 15 and 60 min remained constant. T/B ratios of IMT SPECT and MET PET showed a significant correlation at 15 min postinjection (r = 0.69, n = 10, p = 0.03), a low correlation for the mean values of the scans from 15-60 min postinjection (r = 0.54, n = 14, p = 0.05) and no correlation at 60 min postinjection (r = 0.09, n = 10, n.s.). CONCLUSION: IMT and MET uptake in gliomas is similar in the early, transport dominated phase. There are some differences in tumor to brain ratios between both tracers within the first hour postinjection that are mainly caused by variable washout of IMT. Imaging of tumor extent with IMT SPECT is comparable to MET PET. Thus, amino acid SPECT using IMT is a promising tool to evaluate the biological activity and intracerebral infiltration of gliomas.

Adult↗
PubMed1996

Primary glioblastoma multiforme of the oculomotor nerve. Case report.

Tumors of the oculomotor nerve are rare and most instances reported have been schwannomas. The authors present clinical, neuroradiological, and neuropathological findings in a 70-year-old woman with a glioblastoma multiforme (GBM) growing primarily in the proximal part of the left oculomotor nerve. The patient presented with a 1-month history of transient diplopia. Neurological examination revealed an incomplete left-sided oculomotor nerve palsy with no further signs of neurological dysfunction. Cranial computerized tomography and magnetic resonance imaging showed a tumor of the left oculomotor nerve without any obvious signs of penetration into the midbrain or upper pons. Following subtotal removal of the tumor, neuropathological examination of the operative specimen revealed a GBM that had grown diffusely within peripheral nerve tissue. Six weeks after surgery, the patient suddenly died of pulmonary thromboembolism. Postmortem examination of the brain confirmed a large leptomeningeal GBM at the left pontomesencephalic junction with complete destruction of the left oculomotor nerve. To the authors' knowledge, this represents the first case of a GBM of the oculomotor nerve, probably originating from glial cells within the most proximal part of the nerve or the adjacent leptomeninges.

Aged↗
PubMed1996

Survival in malignant glioma: analysis of prognostic factors with special regard to cytoreductive surgery.

Although the question of optimal treatment for malignant gliomas has been addressed in many retrospective papers, no clear answer has been found to what extent surgical removal of tumor tissue should be performed. We conducted a retrospective analysis in 274 unselected patients, admitted to our institution with the diagnosis of malignant supratentorial glioma. Median survival time after surgery was analyzed with respect to the following defining variables: Age, pre- and postoperative Karnofsky Performance Scale (KPS), tumor location, histology, sex, pre- and postoperative tumor volume and volumetrically measured extent of resection. All these defining variables with exception of sex and preoperative tumor volume were of significant influence on the median survival time of glioma patients (Kolmogoroff-Smirnoff test, Log-Rank test, Breslow test and Tarone-Ware test p < 0,05). To exclude covariant influences of these variables on patients survival and to answer the question of the best surgical option, a matched pair analysis between 40 patients undergoing stereotactic biopsy and 40 patients undergoing cytoreductive surgery was performed. Median survival time (MST) in the biopsy group was 184 days whereas the cytoreductive surgery group had a MST of 292 days (p < 0,05). In addition median postoperative KPS at the point of discharge in patients with tumor resection was slightly better (KPS 58%) in comparison with the biopsy group (KPS 53%) but not on a significant level. It is concluded from these data that patients harbouring malignant gliomas clearly benefit from cytoreductive surgery compared with stereotactic biopsy regarding life expectancy and mildly regarding life quality.

Adolescent↗
PubMed1995

[Lumbar nerve root compression: a cooperative project for quality assurance in neurosurgery].

In 1993 a total of 4152 cases of lumbar nerv root compression have been investigated in 11 neurosurgical departments. Beside patient data diagnostics, treatment and course as well as neurological status before and after treatment were subjects of this quality assurance study. Special emphasis was put on a detailed evaluation of complications. In more than 91% surgical treatment has been performed, in 5% of these cases after an attempt of conservative treatment. Nearly 9% of the patients have not been operated upon. Recurrent disease has been treated surgically in 10.5%. Most common procedure was flavectomy (69%) with discectomy (80%). The all over complication rate was 14%. Typical surgical complications have been rare with 5%. Neurological deterioration after treatment was also rare with less than 2%. The study was able to reflect the present state of treatment in patients with lumbar nerve root compression and the subjects investigated served well as parameters of quality assurance.

Adult↗
PubMed1994

"Ultrahigh" dexamethasone in acute brain injury. Results from a prospective randomized double-blind multicenter trial (GUDHIS). German Ultrahigh Dexamethasone Head Injury Study Group.

In a prospective randomized double-blind multicenter trial, the efficacy and safety of a 51-hour ultra-high intravenous dexamethasone dosing regimen was investigated in patients with moderate and severe head injury. 300 patients between 15 and 55 years of age were randomized to receive either placebo or dexamethasone: 500 mg intravenous infusion within 3 h after trauma initially, followed by 200 mg after 3 h, thereafter 8 times 200 mg at 6 hourly intervals, resulting in a total administered dose of 2,3 g in 51 hours. Primary end points for assessment of efficacy were: Modified Glasgow Coma Scale (grading 3-16) on Day 5, modified Glasgow Outcome Scale (grading 1-6) 10-14 months after injury, and the time interval until consciousness improved above a level of modified GCS > or = 8. Secondary endpoints were CT results and neurological and laboratory data. The two groups were well matched with respect to important prognostic variables, such as age, severity of trauma, and interval between trauma and application of the drug. 269 patients (89.7%) were available for final examination after 10-14 months. Results were surprisingly favourable in both groups: Lethality in the dexamethasone and placebo group was 14.3 and 15.4%, respectively, and 61.7 and 57.4%, respectively, achieved social and professional rehabilitation after 10-14 months (outcome scale 6). No statistical difference was seen between the dexamethasone and the placebo group in any of the primary end points of efficacy and safety (incidence of upper gastrointestinal bleeding, infection, and thrombosis).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

[Quality assurance--an important factor in the structure of medical management of the future].

Quality of medical practice has several prerequisites. A certain structural quality is essential to ensure good quality medical performance. Structural and performance quality both lead to result quality. Performance quality is dependent on well-working structures. With respect to neurosurgery a high level hospital organisation is required which allows equally qualified medical performance. Structure therefore has to attain a standard to stand up to quality assurance criteria. Next to hospital equipment structural quality requires sufficient staff capacity as well as unlimited neurosurgical access to technical equipment such as computerized tomography, MR, angiography and also intensive care under neurosurgical supervision. Quality assurance has been widely discussed in recent years. Measures to guarantee quality assurance, as required by federal law in Germany, are taking three different steps, first a model phase as a scientific study developing methods and observation, a second phase called study phase with wide effects and institution in various departments. In this phase the effectiveness of the procedure is tested and assured. In the third phase routine use is instituted. In quality assurance in neurosurgery phase two is presently tested, phase three is in preparation.

Clinical Competence↗
PubMed1991

[Total parenteral nutrition of neurosurgical patients following elective midline surgery].

The authors report on their results of total parenteral nutrition (TPN) which was performed in a group of 11 comatose patients following elective neuro-surgery of different midline lesions (e.g. tumours, aneurysms of the anterior communicating artery). Carbohydrates were administered from day 1 postoperatively in a dose of 18-24 kcal/kg BW/day. Amino acids were given as a commercially available 12.5% solution (1.4-1.83 g/kg BW/day). Daily routine laboratory values were measured as well as levels of total serum protein, albumin, prealbumin, and retinol-binding protein. Free amino acids in plasma were measured on the day of operation and on day 3, 5, and 7 postoperatively. Renal nitrogen loss was high with maximal values up to 30 gm/day. By TPN cumulative nitrogen balance remained positive until day 2 and was reduced to -61.8 g at the end of the study period. Short-lived serum proteins remained normal. Free FAA's in plasma increased steadily with their highest levels on day 5 and 7 (twice the normal range). Besides slight elevation of liver enzymes and mild hyperglycaemia, no severe changes were observed in routine laboratory parameters. The authors conclude that severe catabolism is a common feature in comatose patients after elective midline surgery and is comparable to catabolism following brain injuries. TPN is well indicated in this group as it preserves visceral protein levels and reduces nitrogen loss without severe side effects.

Adult↗
PubMed1991

Surgery of spinal tumours.

Otfrid Foerster's contribution to neurosurgery was the application of morphological and functional knowledge to the surgical therapy of neurological disease. Kuhlendahl coined the term of patho-biomechanics to explain and subsequently treat spinal pathology in a way still relevant to our surgery. The history of spinal surgery and its pioneers leads us from careful first indications to the classical problems of risks and benefit of tumour surgery in an around the spinal canal, extent of tumour resection and stability of the various spinal segments to modern techniques of intraoperative monitoring, microsurgery and stabilisation procedures. An overview of a multicentre study conducted by the Deutsche Gesellschaft für Neurochirurgie is presented. Some examples taken from our daily work are shown to illustrate the range of procedures in our spinal tumour patients.

Adult↗
PubMed1991

[MRT in syringomyelia--follow-up control after syringo-arachnoid shunt surgery with clinical correlation].

In 8 patients with syringomyelia, MR long-term follow-ups (observation period 25-46 months) were done after syringosubarachnoidal shunt operations. MR showed directly after surgery in 6 cases an extensive collapse of the syringomyelias and in 2 cases a lesser reduction of the diameter of the syrinx. During the subsequent course the size of the cavities increased again in 3 cases. The size of the syrinx visualised by MR did not correlate with the clinical status during the follow-up studies. This seems to point to an insufficient representation of the disease process by the morphological visualisation of the size of the syrinx.

Adult↗
PubMed1990

Continuous monitoring of cerebral tissue pressure in neurosurgical practice--experiences with 100 patients.

The authors present their experience with the use of continuous monitoring of cerebral tissue pressure (CTP) in a neurosurgical intensive care unit. The CTP was monitored in 100 patients with a variety of neurosurgical diseases. In 13 patients simultaneous recording of the ventricular fluid pressure (VFP) was carried out for up to 134 h. In 21 patients intrahemispheric gradients of CTP were recorded and in 66 patients CTP alone was recorded (59 supratentorial, 7 infratentorial). In general CTP monitoring gave excellent results with no additional risk to the patient and low costs for the monitoring system. The behaviour of CTP in various clinical conditions and the indications and limitations of CTP monitoring compared with VFP or epidural pressure monitoring are outlined. The authors recommend monitoring of VFP as the method of choice in ICP supervision. Continuous monitoring of CTP is the preferred method in the posterior fossa, after large craniectomies, for postoperative supervision following open surgery and in cases of narrowed ventricles.

Catheters, Indwelling↗
PubMed1989

Adjuvant intraarterial chemotherapy with nimustine in the management of World Health Organization Grade IV gliomas of the brain. Experience at the Department of Neurosurgery of Düsseldorf University.

A protocol with postoperative adjuvant intraarterial (ia) chemotherapy using nimustine (ACNU) was followed at the University of Düsseldorf (Federal Republic of Germany) after histologic confirmation of malignant glioma of the brain. The first iaACNU procedure was performed within 10 days of surgery, and immediately before postoperative irradiation. After radiotherapy further iaACNU courses were given. The study population consisted of 35 primarily treated malignant gliomas World Health Organization (WHO) Grade IV, i.e., glioblastomas (NIV). Of these tumors 11 showed early progressive disease (PD) (NIV primPD), whereas 24 had stable or responsive disease (NIV SD&RD). Seven patients with recurrent malignant gliomas WHO Grade IV (NIV recurrent) were also treated plus six patients with malignant gliomas WHO Grade III (NIII). Experience with 50 treated patients resulted from this study. The median survival time (MST) for the group NIV was 14.2 months; 41.0% of patients were long-term survivors. The MST for the group NIV primPD was 7.8 months; 9.1% of patients were long-term survivors. For the group NIV SD&RD a MST of 18.3 months and 66.7% of long-term survivors were determined. Patients with recurrent tumors on this treatment protocol had an additional MST of 6.1 months. The total MST after first surgery was 16.2 months. The incidence of complications was low. Systemic complications were infrequent or rare. Retinal disturbances were seen in two patients; leukoencephalopathy was not seen in our patients. In 10% of patients cerebral complications were found, which were irreversible in 2% of patients. Complications could not be assigned unequivocally to the nitrosourea. These results compare favorably with what is reported in the literature, demonstrate the potential value of iaACNU in the treatment of malignant gliomas WHO Grade IV, and should encourage the initiation of a randomized clinical trial of adjuvant iaACNU in the therapy of these tumors. The authors propose iaACNU as a valuable approach in the management of primarily diagnosed malignant gliomas WHO Grade IV, but cannot recommend the delay of iaACNU until the recurrence of a brain tumor.

Adult↗
PubMed1989

[Contrast medium enhanced MRT of tumors of the posterior fossa in children and adolescents].

The results of contrast-enhanced MR in 24 children and adolescents with tumours of the posterior cranial fossa are presented. During initial diagnosis, the majority of tumours showed intensive enhancement with improved demarcation from neighbouring structures. The solid component of a cystic tumour, even when small and not visible on the original scan, could be demonstrated in all cases by means of gadolinium-DTPA. Post-operatively, T2-weighted scans regularly showed areas of high signal strength at the margin of the resection; in the absence of a mass or demonstrable progression, the significance of this is uncertain. In these cases gadolinium-DTPA, because of the function of the blood-brain barrier, greatly increases accuracy in demonstrating residual or recurrent tumours.

Adolescent↗