摘要:

&NA;A comprehensive review of the biochemical organization of the malignant astrocytoma is presented. The review is intended for neurosurgeons. It outlines the metabolic flow of events beginning with energy and substrate utilization, followed by structural components (protein, lipids, etc.) and tumor cell secretory products, and ending with nucleic acid synthesis. Cellular pH, tumor‐induced cerebral edema, tumor blood flow, and tumor necrosis are also considered. (Neurosurgery26:1‐19, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

&NA;Thirty‐three children ranging in age from 8 months to 15 years were treated for gunshot wounds to the brain. Half of the children were less than 10 years old. Fifty‐eight percent died. Mortality was influenced by the trajectory of the bullet, intent to commit suicide, and the neurological status immediately after injury. The age and sex of the child and the caliber of the bullet did not influence survival. Three‐fourths of the deaths occurred within 24 hours of injury, suggesting these patients had a mortal wound from the onset. Eleven of the children were attempting suicide, 9 of whom died; 13 were playing with a gun, 5 of whom died; 2 were shot as innocent bystanders to crimes in progress; 1 was shot while involved in a criminal act; 1 was shot in a hunting accident; and in 2 who died within minutes of arrival, the circumstances of the shooting were not documented. Of the survivors, none was left vegetative after 6 months, 3 had severe disabilities, 9 were moderately disabled, and 2 had a good outcome. The mortality rate is strikingly similar to that of adults with similar injuries; however, the morbidity appears to be less. On the other hand, with simple preventative measures, virtually each injury would have been avoided. (Neurosurgery26:20‐25, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

&NA;A monkey model of transtentorial brain herniation (TBH) was created to simulate the clinically encountered situation of a gradually expanding intracranial lesion. TBH was produced by extradural balloon inflation over a 4‐hour period and documented by the appearance of the pupils as dilated or fixed at midposition. Intracranial pressure (ICP), brain stem auditory evoked potentials (BAEP), and short‐latency somatosensory evoked potentials (SSEP) were recorded before, during, and after TBH. Statistical significance from baseline values to TBH was found for diminution of the BAEP amplitude, rise of the ICP, and diminution of the SSEP amplitude. An ICP rise to twice the baseline value and a 25% decrease in Wave V amplitude was found 1 hour before TBH. Changes in BAEP and SSEP took several minutes after deflation to return to baseline values. Analysis of Wave V of the BAEP was as sensitive as ICP in warning of TBH. Discussion centers upon previous animal studies of brain herniation and ICP elevation, and findings reported in humans deteriorating as a result of intracranial mass lesions. BAEP and SSEP monitoring may be used as noninvasive tests for brain stem compression in the setting of primate TBH, and in the future may be used to guide the effectiveness of therapy. (Neurosurgery26:26‐31, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

&NA;Unteated craniocervical instability is associated with a high morbidity and a significant mortality. Existing methods using bone grafts, interlaminar wires, or acrylic eventually produce stability but require prolonged periods of immobility and have a high failure rate. The ideal method of fixation should provide for permanent correction of deformity and relief of symptoms, with immediate stabilization, at a single procedure. Posterior fixation of the occiput to a stable part of the cervical spine with a molded metal rectangle held in place by interlaminar wires was used to accomplish this. We report 20 patients treated consecutively who have undergone craniocervical fusion by this method using Luque/Hartshill rectangles. Fourteen patients had preexisting atlantoaxial instability and 6 had cord compression, but would become unstable after decompression. All operations were performed under general anesthesia; 9 patients (40%) were awake for intubation/positioning, and 7 patients had a simultaneous decompression. Sixteen patients made an uncomplicated recovery and became mobile 3 days postoperatively. Symptomatic and neurological improvement occurred in 70% of all patients. Neurological complications occurred in 4 patients (20%), reflecting the serious nature of the condition; 2 patients (10%) showed no change. Scrutiny of their presentations and operations failed to identify avoidable risk factors, except faulty wiring techniques. In all patients, permanent stabilization was achieved immediately, facilitating early mobilization with a real chance of improvement, which indicates that the method merits wider application. (Neurosurgery26:32‐36, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

&NA;The effect of exogenous nerve growth factor (NGF) on axonal regeneration into autologous peripheral nerve (PN) grafts implanted to the spinal cord (SC) of rats was assessed by retrograde labeling of the parent soma of the regenerating axons with horseradish peroxidase. NGF was delivered at the graft site over periods of 15 and 30 days by using indwelling osmotic minipumps. In control rats, the minipumps were filled with saline. At 15 days after grafting in the NGF‐treated rats, the mean number of SC as well as dorsal root ganglion (DRG) neurons that regenerated their axons into the peripheral nerve grafts was increased 55.3 and 26.4 times, respectively, as compared to the control group values. At 30 days, SC and DRG neurons in the NGF‐treated group were 10.9 and 3.1 times greater than in the control group. In the NGF‐treated group, the regenerating SC neurons were located within a range of 7 to 13 mm from the graft site as compared to 1 to 7 mm in the control group. Finally, the analysis of the soma diameters of the regenerating neurons showed that NGF enhanced and maintained with time the regenerative response from small‐sized DRG neurons. Therefore, NGF is thought to promote directly the regenerative potential of SC as well as DRG neurons and to exert an indirect glial cell‐mediated effect at the SC‐graft interface. (Neurosurgery26:37‐42, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

&NA;Seventy‐eight cases of meningioma and related tumors were examined independently using a simple and reproducible argyrophilic method for the demonstration of nucleolar organizer regions (AgNORs) and staining with bromodeoxyuridine monoclonal antibody. The mean number of AgNORs per cell and the bromodeoxyuridine labeling index were shown to be linearly related (r = 0.84, P < 0.001). The mean AgNOR number was 2.99 for meningeal sarcoma, 2.29 for anaplastic meningioma, 2.08 for hemangiopericytic meningioma, 1.72 for recurrent meningioma without atypical histological findings, and 1.52 for nonrecurrent meningioma. We noted that the mean number of AgNORs reflected the cellular kinetics of a tumor and was related to histological grade and clinical behavior. (Neurosurgery26:43‐46, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

&NA;The purpose of the present study was to utilize a well‐established rat glioma to evaluate boron neutron capture therapy for the treatment of malignant brain tumors. Boron‐10 (10B) is a stable isotope which, when irradiated with thermal neutrons, produces a capture reaction yielding high linear energy transfer particles (10B +1nth→ [11B] →4He(&agr;) +7Li + 2.79 MeV). The F98 tumor is an anaplastic glioma of CD Fischer rat origin with an aggressive biological behavior similar to that of human glioblastoma multiforme. F98 cells were implanted intracerebrally into the caudate nuclei of Fischer rats. Seven to 12 days later the boron‐10‐enriched polyhedral borane, Na2B12H11SH, was administered intravenously at a dose of 50 mg/kg body weight at varying time intervals ranging from 3 to 23.5 hours before neutron irradiation. Pharmacokinetic studies revealed blood10B values ranging from 0.33 to 10.5 &mgr;g/ml depending upon the time after administration, a T½of 6.2 hours, normal brain10B concentrations of 0.5 &mgr;g/g, and tumor values ranging from 1.1 to 12.8 &mgr;g/g. No therapeutic gain was seen if the capture agent was given at 3 or 6 hours before irradiation with 4 × 1012n/cm2(10 MW‐min; 429 cGy). A 13.5‐hour preirradiation interval resulted in a mean survival of 37.8 days (P< 0.01), compared to 30.5 days (P< 0.03) for irradiated controls and 22.1 days for untreated animals, Rats given the capture agent 16 hours before irradiation had a mean survival time of 41 days (P< 0.005) compared to 27.7 days for unirradiated and 35.8 days (P< 0.01) for irradiated control rats. In vitro studies with F98 cells demonstrated a 3 to 4 log reduction in the surviving fraction using Na2B12H11SH at concentrations of 50 or 100 &mgr;g/ml and a fluence of 1013n/cm2. The in vivo data show enhanced survival in brain tumor‐bearing rats that have been treated by boron neutron capture therapy and the in vitro data suggest that even better results might be achievable if tumor concentrations of10B can be increased. (Neurosurgery26:47‐55, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

&NA;Transcranial Doppler ultrasonography was used to evaluate 2 patients who developed hyperperfusion syndromes after carotid endarterectomy. During the initial postoperative period, each patient had symptoms that were associated with elevated flow velocities in the ipsilateral cerebral vasculature. In addition, vascular resistance of these vessels was found to be abnormally low, as reflected by the Gosling pulsatility index. As the patients' symptoms improved, flow velocities decreased to normal levels and pulsatilities were noted to increase proportionately. (Neurosurgery26:56‐60, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

&NA;Somatosensory evoked potentials (SEPs) were monitored during 113 operations for the clipping of 134 cerebral aneurysms. Changes in peak latency and amplitude of early cortical SEP as well as central conduction time were evaluated. In 58 cases surgical occlusion of arterial vessels or other events occurred, and in 17 of these cases such events were associated with SEP changes or loss. Arterial occlusions resulted from temporary clipping of a feeding blood vessel (22), accidental clipping of a vessel (12). and intentional permanent vessel occlusion (8). A total SEP loss was seen in 2 cases of accidental vessel occlusion and in 6 cases of temporary vessel clipping. Significant SEP changes were found in 6 patients with temporary clipping, and once each with retraction of the cerebellum, retraction of the middle cerebral artery, and after intentional permanent vessel occlusion. Response to these changes included reapplication of aneurysm clips, repositioning of retractors, or removal of temporary clips. Stable SEP signals during 13 cases allowed the surgeon to proceed with the surgical course. Despite the limitations of SEP monitoring in certain anatomical locations, it has been found to be helpful in the operative management of some cases such as multilobed aneurysms of the middle cerebral artery, giant aneurysms, trapping procedures, and procedures requiring temporary vessel occlusion. (Neurosurgery26:61‐70, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

&NA;Thirty‐seven patients with 44 intracavernous carotid artery aneurysms (ICCAAns) were seen at one institution from 1976 through 1988. Fifteen patients had multiple intracranial aneurysms and 7 had bilateral ICCAAns. Age at diagnosis ranged from 15 to 80 (median 61). Thirty patients were women. Sixteen had a history of hypertension. In 34% of patients the ICCAAns were asymptomatic at diagnosis. 36% were associated with headache, and 57% had associated signs or symptoms of mass effect including sixth nerve paresis (43%). trigeminal pain or sensory loss (32%), third nerve paresis (20%), decreased vision or visual field cut (18%), fourth nerve paresis (16%), and Horner's syndrome (7%). In 4 patients the ICCAAns ruptured, leading to subarachnoid hemorrhage in 3 and epistaxis in 1. Two patients with ICCAAns were seen with spontaneous thrombosis of the ipsilateral internal carotid artery leading to distal ischemic symptoms in 1. More than 90% of the ICCAAns were saccular. Thirty‐four percent were small (<1 cm), 48% were large (1 to 2.5 cm), and 16% were giant (>2.5 cm). The majority arose from the anterior genu of the intracavernous internal carotid artery, followed in frequency by the horizontal segment, and then the posterior genu. Magnetic resonance imaging is superior to computed tomography for diagnosing ICCAAns and is the screening procedure of choice. Angiography remains the “gold standard” for diagnosis and determining specific anatomic details necessary to plan therapy. Analyzing the radiographic anatomy of 44 ICCAAns, we conclude that theories attributing the origin of aneurysms to arterial bifurcations may be inadequate to explain the point of origin and direction of take off of up to one‐fourth of ICCAAns. (Neurosurgery26:71‐79, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID