ISSN:1015-9770    

DOI:10.1159/000108441

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:1015-9770    

DOI:10.1159/000108442

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Since the early 1980s, conventional magnetic resonance imaging has demonstrated its usefulness in stroke diagnosis. However, its limitations are obvious, when it is applied to imaging during the first few hours after the onset of ischemia, to the delineation of the ischemic area and to the evaluation of the pathophysiological state of the vessels and brain tissues. Since the late 1980s, new techniques such as fast imaging, magnetic resonance angiography, perfusion imaging, diffusion imaging and MR spectroscopy have been available and used in research. Moreover, these techniques appear to be sensitive enough to allow monitoring of changes due to therapeutics in animal stroke experiments. This review addresses the potential applications of magnetic resonance to acute stroke problems in a clinical setting.

ISSN:1015-9770    

DOI:10.1159/000108443

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Observational epidemiological studies demonstrate a continuous relationship between the level of usual blood pressure and the incidence of stroke. The level of blood pressure appears to be an important determinant of stroke risk in normotensives as well as in hypertensives. Clinical trials of blood pressure reduction in hypertensive patients suggest that much or all of the stroke avoidance associated with a prolonged blood pressure difference of a given magnitude is achieved within a few years of beginning treatment. In this regard, the effects of diuretics and beta-blockers have not been shown to be clearly different. Two important areas for future research in the prevention of stroke concern the effects of blood pressure reduction among individuals with a history of cerebrovascular disease and the effects of antiplatelet therapy in hypertensive individuals.

ISSN:1015-9770    

DOI:10.1159/000108556

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

To determine the clinical usefulness of gadolinium-DPTA-enhanced MRI in identifying recent small, deep infarcts we prospectively studied 91 patients with first-ever stroke and presenting with a lacunar syndrome. In 78 patients (85.7%), plain MRI revealed possibly appropriate infarcts, classified as deep (n = 69), internal borderzone (n = 1), and cortical (n = 8 patients). Enhancement was seen in 38 (80.9%) of 47 patients with only one possibly relevant deep lesion on plain MRI, and in 14 (63.6%) out of 22 patients with multiple lesions. MRI with gadolinium-DPTA facilitates identification of the relevant lesion in patients with presumed lacunar infarcts.

ISSN:1015-9770    

DOI:10.1159/000108444

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

The prevention of stroke is feasible and has been highly successful. Primary prevention related to the management of risk factors has led the way to this success and until recent years the application of these measures has been the only clearly identifiable cause for the remarkable decline in stroke. Evidence is available now which makes it certain that further prevention is possible through antithrombotic treatment and in a selected population by carotid endarterectomy. It is beyond the scope of this presentation to elaborate upon the regulation of risk factors. A summary of the antithrombotic and surgical strategies will be presented.

ISSN:1015-9770    

DOI:10.1159/000108557

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

The hypothesis of an association between stroke mechanisms (cardiac sources of embolism, extracranial large-artery disease, hypertension) and cranial computerized tomography stroke patterns was tested in a prospective study. 200 consecutive patients with focal brain ischemia were investigated by echocardiography (transthoracic and transesophageal approach), Doppler sonography, electrocardiography, and cranial computerized tomography (rated masked). Except for low-flow infarcts and carotid artery stenoses the association between stroke mechanisms and stroke patterns was weak. Lacunes were found with almost equal frequencies in patients with cardiac sources of embolism, extracranial large-artery disease or no extracranial source (with or without hypertension). The predictive value of cranial computerized tomography stroke patterns for the finding of possible stroke mechanisms is low. An embolic etiology of lacunes cannot be excluded.

ISSN:1015-9770    

DOI:10.1159/000108445

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

The cerebroprotective effects of noncompetitive N-methyl-D-aspartate (NMDA) antagonists are well documented in animal focal ischemia models when the agents are administered prior to or just after ischemia begins. However, studies on the delayed administration of these drugs beyond the very acute stage of infarction are few and the results have varied. We assessed the extent of infarction and neurological outcome in 28 rats treated with either CNS-1102 (n = 14), a noncompetitive NMDA antagonist, or saline vehicle (n = 14), 1 h after ischemic onset using an intraluminal occlusion model of stroke. CNS-1102 significantly reduced lesion volume as assessed by 2,3,5,-triphenyltetrazolium chloride staining at 24 h compared to saline-treated rats (120 ± 30 vs. 251 ± 20 mm3, mean ± SEM; p < 0.001). The neurological outcome at 24 h was also significantly better in the CNS-1102-treated animals (p < 0.04). The extent of the infarction was correlated with neurological outcome (p < 0.01); larger lesions were associated with a poorer outcome. The results indicate that the time window for treatment with CNS-1102 is at least 1 h in this rat stroke model. The potential clinical efficacy of this compound is apparent but utility will depend, in part, on its side effect profi

ISSN:1015-9770    

DOI:10.1159/000108446

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

We performed serial transcranial Doppler examinations on 35 patients undergoing 40 consecutive carotid endarterectomies (CEAs) to study alterations in collateral flow and middle cerebral artery (MCA) blood flow velocity. Ipsilateral peri-orbital collateral flow was abolished abruptly in all 16 cases. Compensatory anterior communicating artery collateral was abolished in 17 of 18 cases, and reversed in the other with a remaining severe contralateral carotid lesion. Post-operatively, ipsilateral MCA velocity increased significantly in 26 cases, decreased in 7, and remained unchanged in 7. Sixteen patients had transient hyperperfusion during the first week. Similar changes were observed on the contralateral side. There was no significant association between hyperperfusion and clinical or physiological variables except age. One patient had ipsilateral headache post-operatively associated with hyperperfusion. We conclude that CEA produces rapid alterations of collateral flow and may affect blood flow to both cerebral hemispheres. Transient hyperperfusion, although common, is seldom severe and rarely symptomatic.

ISSN:1015-9770    

DOI:10.1159/000108447

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

We used transesophageal echocardiography (TEE) in 95 consecutive patients after a first cerebral ischemic event in order to find out how much information TEE contributes to the estimation of the risk of subsequent stroke as compared to simple clinical criteria and conventional echocardiography. During a mean follow-up period of 20 months, 12 patients had a second ischemic event. Only 5 of them had initially been stratified into the high-risk group according to either clinical or TEE criteria. The risk of subsequent stroke of patients with pathological TEE exams was only half that of patients assumed to be at high risk according to clinical criteria. Of 16 patients at high risk based upon TEE findings, only 1 had a subsequent event. We conclude that routine TEE does not improve risk estimation in stroke patients.

ISSN:1015-9770    

DOI:10.1159/000108448

出版商:S. Karger AG    

年代:1994

数据来源: Karger