摘要:

MULTIPLE INTRACRANIAL ANEURYSMS (MIA) have been detected in up to one-third of patients with cerebral aneurysms. Three main external factors influence these figures as follows: the quality of angiographies, the quantity of vessels studied, and referral policy. In a 1-year prospective study, we determined the incidence of MIA in a defined catchment area in East Finland by investigating all of the patients with intracranial aneurysms with panangiography. In 114 unselected patients, a total of 170 intracranial aneurysms were detected, and, of these, 39 (34%) harbored MIA. In contrast to most other reports, there was a male predominance in patients with MIA, and half of these men had hypertension. Intracavernous carotid and pericallosal aneurysms were more frequent in patients with MIA. The number of asymptomatic vertebrobasilar aneurysms was extremely low, and most of the nonruptured aneurysms were found in bilateral carotid angiograms. In spite of the active search, the proportion of vertebrobasilar aneurysms remained at 6%. Although our surgical policy was most active, one-third of the asymptomatic aneurysms remained untreated, mainly because of the poor condition of the patient.

ISSN:0148-396X    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

ANEURYSMS OF THE extracranial internal carotid artery (ICA) are uncommon. A significant proportion of such aneurysms are now recognized to be caused by arterial dissection. In some patients, surgical treatment may become necessary. The surgical treatment of 22 patients with spontaneous or traumatic dissecting aneurysms arising from the extracranial ICAs is reviewed. The mean age of the 7 women and 15 men was 39 years. The aneurysm arose from the proximal third of the extracranial ICA in 1 patient, from the middle third in 1 patient, and from the distal third in 20 patients. Five patients underwent cervical carotid ligation; in 13 patients, the aneurysms were resected, and the ICAs were reconstructed, and 4 patients underwent cervical-to-intracranial ICA bypasses. There were 2 postoperative strokes (9%). Facial and lower cranial nerve palsies were commonly seen after high cervical exposure, but these cranial nerve palsies were transient. There were no long-term neurological sequelae during a mean follow-up of 6.2 years. In our relatively limited experience, extracranial ICA dissecting aneurysms can be treated with acceptable morbidity using a variety of techniques. However, the indications for surgical intervention in these aneurysms remain limited.

ISSN:0148-396X    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

THE NATURAL HISTORY of 70 patients affected by low-grade astrocytomas was recorded after the histological diagnosis was obtained by serial stereotactic biopsy. Forty-three percent of these patients died within 3 years. The value of cell kinetics assessment at the time of stereotactic biopsy was investigated, and the labeling index percent may be considered the most accurate prognostic factor in these histologically homogeneous astrocytomas. It has been confirmed that the young age of patients predicts a more favorable course, but the value of this also seems to be linked to and dependent on cell kinetics. These data are discussed in view of the opportunity to perform more aggressive “cytoreductive” treatments in deep brain tumors when these indices support an expected poor prognosis.

ISSN:0148-396X    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

RADIATION-INDUCED DELAYED brain injury is a well-documented complication of both standard external beam radiation (teletherapy) and interstitial brachytherapy; however, the cause of this damage has not been determined. Cytokines and growth factors are important regulatory proteins controlling the growth and differentiation of normal and malignant glial cells, which have been implicated in the tissue response to radiation injury. Six snap-frozen brain biopsies showing radiation injury were obtained from four patients harboring malignant gliomas who underwent either postoperative external beam and/or stereotactic interstitial brachytherapy at standard dosages. The specimens showed variable amounts of gliosis, tissue necrosis, calcification, inflammation, and vascular proliferation and hyalinization. Frozen tissue sections were examined for the presence of infiltrating lymphocytes, macrophages, cytokines, and other immunoregulatory molecules by the use of a panel of specific monoclonal and polyclonal antibodies. All specimens showed diffuse T cell infiltration with both CD4+and CD8+cells. Infiltrating activated macrophages (CD11c+, HLA-DR+) were prominent in five of six cases. Tumor necrosis factor-α and interleukin-6 immunoreactivity was prominent in four of six cases and was predominately localized to macrophages. Transforming growth factor-β astrocytic and macrophage immunoreactivity was present at moderate levels in all cases. This study suggests that in radiation necrosis, interleukin-1α, tumor necrosis factor-α, and interleukin-6 are expressed, predominately by infiltrating macrophages.

ISSN:0148-396X    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

THE WILD-TYPE p53 gene is thought to play a critical role in tumor suppression and has been shown to reverse the transformed phenotype of tumor cells in vitro. Mutational inactivation of this aspect of p53 activity occurs frequently in many human neoplasms, including astrocytomas, and is thought to represent a critical step in tumor progression. We have found previously that the presence of p53 immunoreactivity was significantly associated with malignant astrocytomas arising in younger patients, although occurring infrequently in tumors in older patients. Given that young age is the most consistent clinical factor predictive of longer survival in patients with astrocytomas, this suggested that p53 protein accumulation might be a molecular predictor of enhanced survival. To test this hypothesis, we retrospectively studied the association of p53 overexpression with survival in 149 patients with astrocytomas, using univariate and multivariate analysis to determine its value in predicting survival. Although our analysis reaffirmed the strong association between young age and increased survival, we were unable to demonstrate any difference in survival between patients with Grade III and IV tumors with p53 immunoreactivity compared with those without. Presumably, once a tumor has progressed to high grade, the relative importance of p53 status as a predictor of survival is low, probably because of the large number of accumulated genetic alterations associated with malignant tumors. In contrast, the presence of p53 overexpression in Grade II astrocytomas seemed from survival curves to indicate shorter survival compared with patients who had no p53 immunoreactivity. However, this variable did not quite reach statistical significance (P= 0.08) as an independent predictive variable in multivariate analysis. This may be because of the relatively small population of patients with Grade II tumors that were studied (n = 24). However, patients with histological evidence of malignant degeneration had significantly higher levels of p53 staining than those with no evidence of progression. These data are consistent with the likely role of p53 in driving the clonal expansion of a dominant cell type during malignant progression and suggest that p53 overexpression may prove to be a molecular marker for prognosis in patients with Grade II astrocytomas.

ISSN:0148-396X    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

DATA FROM 95 adult patients (43 males, 52 females) treated with ventriculoperitoneal shunts during an 8-year period were analyzed to investigate risk factors in shunt surgery. All patients were seen in the authors' department and were grouped according to the cause or type of hydrocephalus. The operating surgeons were divided into two categories: specialists and residents. The shunts were classified as single- (Orbis-Sigma) or multicomponent (Holter or Hakim) systems. Two types of unfavorable events were recognized: complications and shunt malfunction. A total of 143 surgical procedures (implantations and revisions) were performed in the 95 patients; 24 patients had their shunts revised, and there were 13 complications (one fatal, five severe) resulting from the shunt surgery. The following observations were statistically significant: 1) patients with normal pressure hydrocephalus had no complications from shunt surgery; 2) the number of shunt malfunctions was lower in patients with intracranial hemorrhages than in the other groups; 3) residents performed a higher number of inadequate operations than did specialists; and 4) the infection rate was higher among patients operated on by residents. The choice of shunt type, the perioperative use of antibiotics, and the degree of surgical emergency were not correlated with complication or failure rates.

ISSN:0148-396X    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

THE NEED TO obtain histological diagnoses of intracranial tuberculomas, before initiating therapy, is not universally accepted, because some clinicians believe that an image-based diagnosis is fairly accurate in patients from endemic regions. To evaluate the sensitivity, specificity, and predictive value of computed tomography (CT)-based diagnosis of an intracranial tuberculoma, we prospectively compared the preoperative imaging diagnoses with histological diagnoses in 105 consecutive patients with intracranial masses. CT differential diagnoses (first or second) of tuberculomas were considered in 21 patients. Seven of them were histologically confirmed to have tuberculomas (true-positive results); 14 had other diseases (false-positive results). The 14 false-positive cases included 6 cases of astrocytomas, 5 of metastases, and 3 with miscellaneous diagnoses. All tuberculomas were correctly diagnosed on the CT scans (5 by both surgeons and 2 by one surgeon). During the study period, we encountered 11 patients who were referred by other clinicians with diagnoses of tuberculomas on the basis of their CT scans. We concurred with their CT diagnoses in 5 of them, but only 1 patient had a histologically verified tuberculoma. Astrocytomas (4 patients), metastases (3 patients), and solitary cysticercus granulomas (3 patients) were the causes of misdiagnosis in this group of patients. Although the sensitivity of CT in the diagnosis of intracranial tuberculomas is 100%, and its specificity is 85.7%, the positive predictive value is only 33% (confidence limits, 24–42%). The negative predictive value is 100%. The low positive predictive value for a diagnosis of intracranial tuberculoma on CT alone indicates the need for a confirming histological diagnosis.

ISSN:0148-396X    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

ACINETOBACTER ANITRATUSHAS emerged as one of the common pathogens responsible for postneurosurgical meningitis at the authors' institution. Seven patients withAcinetobactermeningitis were identified during the 4-year period of this study, five of whom acquired organisms susceptible only to imipenem and amikacin.Acinetobacterbacteremia occurred concomitantly in five patients. Despite late institution of therapy as a result either of organism misidentification on Gram stain or of unexpected acquisition of a highly resistant organism, the patients' outcome was favorable after the initiation of appropriate antibiotic therapy. Imipenem and amikacin, with or without intrathecal aminoglycosides, were effective in patients with resistant strains ofAcinetobacter.

ISSN:0148-396X    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

WE HAVE RETROSPECTIVELY studied 11 cases of solitary cavernous and arteriovenous malformations of the spinal epidural space. The acute or subacute onset of symptoms was found in all cases, with a neurological deficit in five cases. A plain x-ray study revealed abnormal calcification in one case. Hyperdensity with no iodine enhancement was found on computed tomographic scans in all cases. Magnetic resonance imaging studies showed ovoid or round lesions with isosignal and gadolinium enhancement on T1-weighted images and hypersignal on T2-weighted images, except in one case with hypersignal on T1 and T2 before the administration of a contrast medium. Four lumbar cases were localized in the posterior vertebral ligament; all the thoracic cases were posterior with foraminal extension. The other cases were anterolateral. The surgical findings revealed a dark vascularized epidural lesion associated in two cases with a localized epidural hematoma. A pathological examination revealed seven cavernous angiomas and four arteriovenous malformations. These arteriovenous malformations were all lumbar, and two of four localized within the posterior ligament. The pathophysiology of these vascular malformations is discussed. In light of the good postoperative prognosis of these lesions, surgical removal is recommended for all the symptomatic cases.

ISSN:0148-396X    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

DURING THE PERIOD from 1977 to August 1992, 100 intramedullary tumors in 94 patients were operated on in the Department of Neurosurgery at the Nordstadt Hospital in Hannover, Germany. Of these, 45% presented with associated syringes. A syrinx was more likely to be found above (49%) than below (11%) the tumor level. In 40%, a syrinx could be identified above and below the tumor level. Ependymomas and hemangioblastomas were the most common tumor types to be associated with syringes. Astrocytomas tended to demonstrate syringes less often. Regardless of histology, the higher the spinal level, the more likely a syrinx was encountered. In general, the presence of an associated syrinx favored the resectability of the tumor, because it indicated a displacing rather than an infiltrating tumor. Patients with syringomyelia tended to recover from surgery sooner. However, surgical results and long-term prognosis were not influenced significantly by an associated syrinx. The most important factor determining long-term outcome was the preoperative level of neurological function. We propose that factors independent of the tumor, disturbances of cerebrospinal fluid and extracellular fluid flow in particular, have major roles in the pathogenesis of syrinx formation associated with intramedullary tumors.

ISSN:0148-396X    

出版商:OVID    

年代:1994

数据来源: OVID