摘要:

OBJECTIVE:Radical resection of meningiomas and dural arteriovenous fistulas involving functional major dural sinuses entails the risk of intracranial hypertension and venous infarction. Surgical reconstruction of dural sinuses and bridging veins increases the spectrum of dural sinus conditions that can be treated by complete resection, but indications for venous reconstructions and associated risks are still not well defined. We report our experience with sinus reconstruction based on the intraoperative assessment of collateral venous flow.METHODS:Radical resection of meningiomas (n = 5) or dural arteriovenous fistulas(n = 5) involving critical segments of dural sinuses was performed in 10 patients. All but two patients were suffering from recurrent disease after incomplete treatment. Tolerance of sinus occlusion was assessed intraoperatively by measuring stump pressure in the superior sagittal sinus during test clamping of the involved sinus segment.RESULTS:In five patients, the results of pressure monitoring suggested that occlusion of the sinus might not be tolerated. In two other patients, major bridging veins entered the diseased segment. In these patients, the resected sinus segment was reconstructed and bridging veins were reinserted as far as possible. Postoperative graft occlusion occurred in two patients. One patient who was managed without reconstruction sustained a transient postoperative neurological deficit resulting from venous congestion in the vein of Labbé. Postoperative imaging confirmed total elimination of the pathological process in all 10 patients. There was no recurrence of disease during follow-up periods of up to 8 years.CONCLUSION:The monitoring of sinus pressure, together with the possible reconstruction of the diseased sinus, allows complete surgical treatment of dural sinus abnormalities and involves acceptable risk.

ISSN:0148-396X    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:0148-396X    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

OBJECTIVE:Radiosurgery is increasingly being used to treat cranial base tumors. Since 1989, 55 patients with cranial base meningiomas were treated at Stanford University Medical Center with linear accelerator radiosurgery. An analysis of the clinical and radiographic results of this patient population was the focus of this study.METHODS:The mean patient age was 55.1 years (range, 28-82 yr). The mean tumor volume was 7.33 cm3(range, 0.45-27.65 cm3). The radiation dose averaged 18.3 Gy (range, 12-25 Gy), delivered with an average of 2.2 isocenters (range, 1-5). Patients were evaluated retrospectively through clinic notes from follow-up examinations, and residual tumor volume was measured during follow-up imaging studies. The length of follow-up averaged 48.4 months (range, 17-81 mo).RESULTS:Tumor stabilization after radiosurgery was noted in 38 patients (69%), shrinkage in 16 patients (29%), and enlargement in only 1 patient (2%). The results of follow-up magnetic resonance imaging demonstrated decreased central contrast uptake in 11 meningiomas (20%), possibly indicating evidence of central tumor necrosis or tumor vessel obliteration. Neurological status was improved in 15 patients in the series (27%) and unchanged in 34 patients(62%). Three patients (5%) died during the follow-up period, all as a result of causes other than tumor progression. Three patients (5%) developed new permanent symptoms (one patient with seizures, one patient with mild right hemiparesis, and one patient with both vagal and hypoglossal nerve palsy). All other complications were transient, including partial trigeminal nerve palsy in seven patients and diplopia in three patients. The 2-year actuarial tumor control rate was 98%.CONCLUSION:Although our follow-up period is short, this experience corroborates previous reports that radio-surgery can be used to ablate selected small cranial base meningiomas, with good clinical results and modest morbidity.

ISSN:0148-396X    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

OBJECTIVE:This study used quantitative radiological imaging to determine the effect of surgical resection on postoperative survival of patients with malignant astrocytomas. Previous studies relied on the surgeons' impressions of the amount of tumor removed, which is a less reliable measure of the extent of resection.METHODS:Information concerning possible prognostic factors was collected for 75 patients undergoing magnetic resonance imaging or computed tomography preoperatively and within 10 days postoperatively. Image analysis of the neuroradiological studies was conducted to quantify pre- and postoperative total tumor volumes and enhancing volumes. Univariate and multivariate proportional hazards models were used to analyze the regression of survival regarding 22 covariates that might affect survival. The covariates that were entered included age, gender, tumor grade, cumulative radiation dose, chemotherapy, seizures as a first symptom, Karnofsky performance status at presentation, pre- and postoperative total and enhancing tumor volumes, ratio of pre- to postoperative total and enhancing tumor volumes, tumor location, surgeon's impression of the degree of resection, and subsequent surgery.RESULTS:There were 23 patients with anaplastic astrocytomas and 52 with glioblastomas multiforme. The estimated mean survival time was 27 months for patients undergoing gross total resection, 33 months for subtotal resection, and 13 months for open or stereotactic biopsy. Five factors that were significant predictors of survival in multivariate analysis were tumor grade, age, Karnofsky performance status, radiation dose, and postoperative complications (P< 0.05). In univariate analysis, tumor grade, radiation dose, age, Karnofsky status, complications, presence of enhancing tumor in postoperative imaging, and postoperative volume of enhancing tumor were significantly associated with survival (P< 0.05).CONCLUSION:We conclude that the most important prognostic factors affecting survival of patients with anaplastic astrocytomas and glioblastomas multiforme are tumor grade, age, preoperative performance status, and radiation therapy. Postoperative complications adversely affect survival. Aggressive surgical resection did not impart a significant increase in survival time. Surgical resection may improve survival, but its importance is less that of other factors and may be demonstrable only by larger studies.

ISSN:0148-396X    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

OBJECTIVE:The goals of this clinical trial of intraventricular 454A12-rRA therapy were to identify dose-limiting toxicities, to evaluate the pharmacokinetics of single-dose intraventricular 454A12-rRA, and to detect antitumor activity.METHODS:We performed a pilot study of intraventricular therapy with the immunotoxin 454A12-rRA in eight patients with leptomeningeal spread of systemic neoplasia. The immunotoxin 454A12-rRA is a conjugate of a monoclonal antibody against the human transferrin receptor and recombinant ricin A chain, the enzymatically active subunit of the protein toxin ricin. Patients were treated with single doses of 454A12-rRA ranging from 1.2 to 1200µg.RESULTS:The early phase half-life of 454A12-rRA in ventricular cerebrospinal fluid(CSF) averaged 44 ± 21 minutes, and the late phase half-life averaged 237 ± 86 minutes. The clearance of the immunotoxin was faster than the clearance of coinjected technetium-99m-diethylenetriamine penta-acetic acid, averaging approximately 2.4-fold greater. No 454A12-rRA degradation was detected by Western blot analysis of ventricular CSF for a period of 24 hours, and bioactivity was retained in CSF paralleling the concentration of immunotoxin. No acute or chronic drug toxicity was identified in patients who received less than or equal to 38 µg of 454A12-rRA by intraventricular injection. Doses more than or equal to 120 µg caused a CSF inflammatory response that was associated with transient headache, vomiting, and altered mental status. This acute syndrome was responsive to steroids and CSF drainage. No systemic toxicity was detected. In four of the eight patients, a greater than 50% reduction of tumor cell counts in the lumbar CSF occurred within 5 to 7 days after the intraventricular dose of 454A12-rRA; however, no patient had their CSF cleared of tumor, and clinical or magnetic resonance imaging evidence of tumor progression was demonstrated in seven of the eight patients after treatment.CONCLUSION:Tumoricidal concentrations of the immunotoxin 454A12-rRA can be attained safely in the CSF of patients with leptomeningeal tumor spread.

ISSN:0148-396X    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:0148-396X    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

OBJECTIVE:Tenascin-C (TN) is an extracellular matrix glycoprotein with a characteristic six-armed structure. The aim of this study was to determine whether the concentration of TN in the cyst fluid of brain tumors can be used as a marker for angiogenesis and glioma grade.METHODS:We investigated the expression of TN in the cyst wall and cyst fluid of human brain tumors by immunohistochemistry, immunoprecipitation, and immunoblotting. The tumors included 12 astrocytomas (5 glioblastoma multiforme tumors, 1 anaplastic astrocytoma, 1 low-grade astrocytoma, 4 juvenile pilocytic astrocytomas, and 1 mixed glioma), 2 dysembryoplastic neuroepithelial tumors, 3 craniopharyngiomas, 2 ependymomas, 2 metastatic carcinomas, 3 arachnoid cysts, 1 glial ependymal cyst, and 1 inflammatory cyst.RESULTS:We detected no expression of TN in the cyst fluids of the ependymomas, craniopharyngiomas, and nonpilocytic low-grade astrocytoma. By contrast, TN was detected in the cyst fluids of all the other tumors. Results of quantitative immunoblotting using a Phosphorlmager unit (Molecular Dynamics, Sunnyvale, CA) revealed that, on average, a 5-fold higher signal was observed in the glioblastoma multiforme tumors as compared with the anaplastic astrocytoma, and a 10-fold higher signal as compared with the mixed glioma, juvenile pilocytic astrocytomas, and dysembryoplastic neuroepithelial tumors. Results of TN immunohistochemistry in the astrocytomas correlated with glioma grade, with stronger staining of the hyperplastic vessels and tumor cells being observed in higher grade gliomas. No TN immunoreactivity was detected in the walls of the ependymomas, arachnoid cysts, and glial ependymal cyst that lack hyperplastic vessels, and minimal TN immunoreactivity was observed in the perivascular gliotic rim of the craniopharyngiomas. No TN was detected in the cyst fluid of these cystic processes.CONCLUSION:The presence of TN in and around the hyperplastic vessels and tumor cells present in the cyst walls of astrocytomas and its deposition in the intratumoral cyst fluid in which angiogenic factors have been detected further suggests a role for TN as an angiogenic modulator. These preliminary results suggest that immunodetection of TN in the tumor cyst fluid may indicate tumor type and grade.

ISSN:0148-396X    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

OBJECTIVE:It is generally considered that mass effect caused by arteriovenous malformations (AVMs) is evidence of ruptures. In the present study, the incidence of mass effect in clinically unruptured AVMs was evaluated, and the underlying causative factors and pathophysiological mechanisms were studied.METHODS:Twenty-seven patients with clinically unruptured supratentorial pial AVMs were examined. The majority were suffering from epilepsy, and frontal lobe involvement was revealed in approximately half of the patients. Angiographic studies, computed tomographic scans, and magnetic resonance images were obtained for all patients. Twenty-one patients underwent removal of AVMs. In 10 of the surgically treated patients, intraoperative vascular pressure measurements were obtained before removal of the AVMs.RESULTS:Mass effect was detected in 12 (44%) of the 27 patients. Cortical sulci obliteration (eight patients) and lateral ventricle displacement (seven patients) were frequently noted. The volume of AVMs was significantly larger in patients with mass effect than in those without mass effect (P< 0.001). Large dilated venous sacs or ectatic veins were observed to be associated with mass effect (P< 0.001). In only one patient was gross displacement related to a surrounding massive brain edema. Draining vein pressure in patients with mass effect was significantly elevated as compared to the average value in patients without mass effect (22 ± 5 versus 12 ± 3 mm Hg) (P< 0.01).CONCLUSION:The present study suggests that mass effect is not infrequent in clinically unruptured AVMs. Furthermore, multiple causative factors were detected, including the large size of AVMs, marked draining vein dilatation, and brain edema around the AVMs. Findings also indicated that a pathophysiologically high pressure in the venous drainage system may contribute to mass effect.

ISSN:0148-396X    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

OBJECTIVE:We evaluated and analyzed the effect of superficial temporal artery to middle cerebral artery bypass for internal carotid artery occlusion on pure motor function using motor activation single photon emission computed tomography.METHODS:Motor activation single photon emission computed tomographic (SPECT) images were obtained for nine patients who had undergone superficial temporal artery to middle cerebral artery anastomosis for symptomatic internal carotid artery occlusion. All motor activation SPECT images using the finger opposition task on the affected side were obtained before bypass surgery and at 1 week, 1 month, and 3 months after bypass surgery. The results of motor activation single photon emission computed tomography were expressed as negative or positive.RESULTS:Before bypass surgery, the resting SPECT images revealed reduction of cerebral blood flow (CBF) on the affected side in all nine patients. The results of motor activation single photon emission computed tomography in three patients were positive. One week after bypass surgery, the results of the resting and motor activation CBF studies did not demonstrate any marked changes. One month after bypass surgery, the resting CBF increased in four patients. The results obtained for two of the patients revealed preoperative positive motor activation. The results of motor activation single photon emission computed tomography obtained for five patients were positive. Three months after bypass surgery, eight patients experienced improvement in the resting CBF, and the results of motor activation single photon emission computed tomography obtained for seven patients were positive. Among these, the results of preoperative motor activation single photon emission tomography obtained for four patients were negative.CONCLUSION:Superficial temporal artery to middle cerebral artery bypass is useful not only for resting CBF but also for pure motor function based on motor activation SPECT images. From the preoperative motor activation study, it was concluded that patients with preoperative positive motor activation could attain the effect of bypass earlier than patients with preoperative negative motor activation.

ISSN:0148-396X    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

OBJECTIVE:To determine the incidence and risk factors of surgical site infections(SSIs) after craniotomy and to test the risk index score proposed by the National Nosocomial Infections Surveillance (NNIS) system, which, to our knowledge, has not been validated in neurosurgery to date.METHODS:During a 15-month period, every adult patient undergoing craniotomy in 10 neurosurgical units was prospectively evaluated for development and risk factors of SSI. The follow-up period was at least 30 days. SSIs were defined according to the Center for Disease Control definitions. Incidence was calculated per patient. Multivariate analyses were conducted at first to include all significant risk factors of univariate analysis and then only those known preoperatively. Finally, the NNIS risk index was tested in this population.RESULTS:Of a total of 2944 patients, 117 patients (4%) with SSIs were observed, including 30 with wound infections, 14 with bone flap osteitis, 56 with meningitis, and 17 with brain abscesses. Independent risk factors for SSIs were postoperative cerebrospinal fluid leakage (odds ratio, 145; 95% confidence interval, 72-293) and subsequent operation (odds ratio, 7; 95% confidence interval, 4-12). Independent predictive risk factors were emergency surgery, clean-contaminated and dirty surgery, an operative time longer than 4 hours, and recent neurosurgery. Absence of antibiotic prophylaxis was not a risk factor. The NNIS risk index was effective in identifying at-risk patients.CONCLUSION:Independent risk factors for SSIs after craniotomy involve postoperative events. However, the NNIS risk index is effective in identifying at-risk patients.

ISSN:0148-396X    

出版商:OVID    

年代:1997

数据来源: OVID