ISSN:0148-396X    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0148-396X    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0148-396X    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

OBJECTIVE:To define and discuss elements of the escalation in scientific data availability and their importance to neurosurgery.METHODS:This multifactorial essay describes the evolution of communication methodologies, the information revolution, and the advent and effect of Internet communication with its potential effect on the practice of neurosurgery, professional assemblies, journals, and the infrastructure of the discipline. Practical and philosophical viewpoints are rendered to assess the existing and developing availability of information to the neurosurgical community.CONCLUSION:Knowledge must be discerned from information. The individual does not have the luxury of detachment and must remain consistently, intellectually, and actively involved in the adaptations required to stay truly informed and current.

ISSN:0148-396X    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

TWO OLD AND simple concepts, a three-dimensional positioning stage and a coordinate system, were combined in 1906 to create a new one: the stereotactic method. For 25 years, it found little application until it was rediscovered for investigations in small animals. After the first human subcortical stereotactic procedure was performed in 1947, stereotactic methods found greatest application in the placement of subcortical lesions in the treatment of movement disorders. Rapid advances in the development of instrumentation, methods, and understanding of human neuroanatomy and neurophysiology resulted. However, a dormant period followed the introduction ofL-dopa in 1968. The advent of computer-based medical imaging applied to the stereotactic method encouraged adaptation of stereotactic methods to the management of intracranial tumors, the rapid development of new surgical hardware, and the rediscovery of old methods and evolution of new ones for the treatment of movement disorders. In addition, the incorporation of computer systems as stereotactic surgical instruments further increased the capabilities of stereotactic methods. Radiosurgical applications increased with the proliferation of gamma units and the development of linear accelerator-based radiosurgical methods. Computers are used to fuse and reformat imaging databases for surgical planning, simulation, and frameless stereotactic intraoperative guidance. As a result, surgical procedures have become more effective in meeting preoperative goals and less invasive. Low-cost, high-speed, microprocessor-based workstation computers and intuitive user interfaces have increased the acceptance into mainstream neurosurgery. It is anticipated that a significant portion of neurosurgery, and probably most surgical procedures in general, will comprise computer-based interventions guided by volumetric imaging-defined data sets acquired preoperatively or by intraoperative imaging systems. The stereotactic surgery of the future may employ all or a combination of the following technologies: frameless stereotactic surgery, robotic technology, microrobotic dexterity enhancement, and telepresence robotics.

ISSN:0148-396X    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

OBJECTIVE:Accurate outcome prediction after high-grade subarachnoid hemorrhage remains imprecise. Several clinical grading scales are in common use, but the timing of grading and changes in grade after admission have not been carefully evaluated. We hypothesized that these latter factors could have a significant impact on outcome prediction.METHODS:Fifty-six consecutive patients with altered mental status after subarachnoid hemorrhage, who were managed at a single institution, were studied retrospectively. On the basis of prospectively assessed elements of the clinical examination, each patient was graded at admission, at best before treatment, at worst before treatment, immediately before treatment, and at best within 24 hours after treatment of the aneurysm using the Glasgow Coma Scale (GCS), the World Federation of Neurological Surgeons (WFNS) scale, and the Hunt and Hess scale. Outcome at 6 months was determined using a modification of the Glasgow Outcome Scale validated against the Karnofsky scale. All grades and clinical and radiographic data collected were compared among good and poor outcome groups. Multivariate analyses were then performed to determine which grading scale, which time of grading, and which other factors were correlated with and contributed significantly to outcome prediction.RESULTS:A good outcome was achieved in 24 (43%) of 56 patients. Our study also had a 32% mortality rate. With the Hunt and Hess scale, only the worst pretreatment grade was significantly correlated with outcome. However, with the GCS and the WFNS scale, grading at all pretreatment times was significantly correlated with outcome, although outcome was best predicted before treatment, regardless of the scale used, if grading was performed at the patient’s clinical worst. Multivariate analysis revealed that the best predictor of outcome was WFNS grade at clinical worst before treatment. Used alone, a WFNS Grade 3 at worst pretreatment predicted a 75% favorable outcome, and a WFNS Grade 5 at worst pretreatment predicted an 87% poor outcome. No significant correlation was found between direction or magnitude of change in grade and outcome. Age was found to be significantly correlated with outcome, but it was only an independent factor in outcome prediction when used in conjunction with the Hunt and Hess scale and not with the WFNS scale and the GCS.CONCLUSION:Timing of grading is an important factor in outcome prediction that needs to be standardized. This study suggests that the patient’s worst clinical grade is most predictive of outcome, especially when the patient is assessed using the WFNS scale or the GCS.

ISSN:0148-396X    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0148-396X    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

OBJECTIVE:To examine the potential role of cerebral revascularization in the treatment of patients with symptomatic occlusive cerebrovascular disease refractory to medical therapy.METHODS:Twenty patients with symptomatic occlusive cerebrovascular disease underwent 22 extracranial-intracranial bypass procedures after failing maximal medical therapy. The average follow-up time was 3.5 years, and no patient was lost to follow-up.RESULTS:All patients presented with repeated transient ischemic attacks refractory to medical therapy. Angiographic findings included internal carotid artery occlusion in 8 patients, middle cerebral artery stenosis or occlusion in 4, moyamoya disease in 4, internal carotid artery dissection in 2, and supraclinoid internal carotid artery stenosis in 2. Outcome was excellent in 17 patients and good in 3. The only surgical complication occurred in one patient, who experienced postoperative seizures and required anticonvulsant therapy. There were no deaths in this series.CONCLUSION:Although the Cooperative Study on Extracranial-Intracranial Bypass failed to show a benefit from the bypass procedure, we have continued to perform the operation in selected cases. Carefully selected individuals with occlusive cerebrovascular disease and persistent ischemic symptoms, despite maximal medical therapy, seem to obtain demonstrable and durable benefit from cerebral revascularization.

ISSN:0148-396X    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

OBJECTIVE:Intracranial aneurysm size is an important determinant of risk of rupture and outcome after rupture. Risk factors influencing aneurysm formation and growth are not well defined. In this study, we examined the association between known risk factors for cerebrovascular disease and size of intracranial aneurysms in patients with aneurysmal subarachnoid hemorrhage.METHODS:We analyzed prospectively collected data from the placebo-treated group in a multicenter clinical trial conducted at 54 neurosurgical centers in North America. The presence, location, and size of intracranial aneurysms were determined by review of the admission angiograms. Pertinent information regarding the presence of various cerebrovascular risk factors was collected for each patient. Using logistic regression analysis, we identified independent determinants of aneurysm size from demographic, clinical, and angiographic characteristics of the participants. The impact of aneurysm size on 3-month mortality was analyzed after adjusting for potential confounding factors.RESULTS:For 298 patients admitted with subarachnoid hemorrhage, the ruptured aneurysms were graded as small (<13 mm) in 235 patients (79%) and large (≥13 mm) in 63 patients (21%). In the logistic regression model, both smoking at any time (odds ratio, 2.2; 95% confidence interval, 1.1–4.5) and middle cerebral artery origin (odds ratio, 2.5; 95% confidence interval, 1.3–4.9) were independently associated with large aneurysms. Neither hypertension, diabetes mellitus, nor alcohol and illicit drug use were associated with large-sized aneurysms. After adjusting for initial Glasgow Coma Scale score and age in the logistic regression model, the presence of large-sized aneurysms was independently associated with 3-month mortality (odds ratio, 2.3; 95% confidence interval, 1.1–4.8).CONCLUSION:Cigarette smoking and middle cerebral artery origin seem to increase the risk for developing large aneurysms in patients predisposed to intracranial aneurysm formation. Further studies are required to investigate the mechanism underlying the association between cigarette smoking and intracranial aneurysm formation.

ISSN:0148-396X    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

OBJECTIVE:Patients with non-acquired immunodeficiency syndrome-related primary central nervous system lymphomas have the potential to achieve durable complete responses without radiotherapy, with treatment using enhanced chemotherapy delivery with blood-brain barrier disruption (BBBD). Reported 5-year survival rates with combined chemotherapy and radiotherapy were generally only 9 to 22% and were associated, in one study, with an overall 32% incidence of overt dementia and ataxia, which are dramatically increased among patients more than 60 years of age.METHODS:At the Oregon Health Sciences University, 111 consecutive patients with non-acquired immunodeficiency syndrome-related central nervous system lymphomas were prospectively treated with methotrexate-based, BBBD-enhanced chemotherapy and underwent formal neuropsychological evaluations. Of those, 74 patients had no systemic lymphoma and had received no prior irradiation; those 74 patients are described in this report.RESULTS:The estimated 5-year survival rate for this group was 42%, and the median survival time was 40.7 months. Overall, 48 patients (65%) exhibited complete responses and 36 patients continued to exhibit complete responses after 1 year of BBBD-enhanced chemotherapy. Of those 36 patients, none demonstrated evidence of cognitive loss in neuropsychological tests and/or clinical examinations.CONCLUSION:BBBD-enhanced chemotherapy delivery, without subsequent radiotherapy, resulted in favorable survival and cognitive outcomes for patients with primary central nervous system lymphomas who had not previously undergone irradiation. A cooperative multicenter study of intravenous chemotherapy without radiotherapy versus BBBD-enhanced chemotherapy would address the feasibility and necessity of performing a Phase III study for these rare central nervous system malignancies.

ISSN:0148-396X    

出版商:OVID    

年代:2000

数据来源: OVID