ISSN:1015-9770    

DOI:10.1159/000108808

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

One hundred cases of isolated angiopathy of the central nervous system (CNS) have been described, the majority of whom (71%) were diagnosed histologically. The pathological findings were those of angiitis, most frequently granulomatous angiitis. These patients should be classified as isolated angiitis of the CNS. The minority of patients (29%) were diagnosed according to clinical and angiographic findings which lack sensitivity and specificity. They represent a heterogeneous group, comprising several cases of probable isolated angiitis of the CNS, some clinical and angiographic syndromes associated with acute hypertension, subarachnoid haemorrhage or migraine and other more obscure ''entities'' such as post-partum cerebral angiopathy and isolated benign cerebral angiopathy. In the absence of a histological diagnosis, it is preferable to classify them as isolated angiopathy of the CNS. Although isolated angiitis of the CNS can be considered a discrete, or at least definable, subset of isolated angiopathy of the CNS, it is unclear whether it is a specific disorder or part of a spectrum of disease or even one of a number of reactions to various antigens. The finding of granulomatous angiitis of the CNS (GACNS) in several patients with various systemic disorders suggests that GACNS may be a non-specific pathological reaction. Until the last decade, the prognosis of isolated angiitis of the CNS was extremely poor. Most patients now survive and return to active lives. The major influence on outcome appears to have been the use of combination corticosteroid and cyclophosphamide therapy, although no randomized controlled trials have been undertaken. Before prolonged treatment with such potent medication is prescribed, it recommended that other causes of CNS vasculitis be carefully excluded and the diagnosis of isolated angiitis of the CNS be established histologically by combined leptomeningeal and parenchymal biopsy. The risks of biopsy would not appear to exceed those of untreated isolated angiitis of the CNS. Multicentre collaboration of interested groups should be encouraged if controlled therapeutic trials are to be achieved.

ISSN:1015-9770    

DOI:10.1159/000108809

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

A community-based survey of the prevalence of carotid-artery stenosis in subjects older than 49 years has been carried out in the health district of Baiano di Spoleto (Umbria, Italy). Out of 388 randomly selected residents, 320 had a Doppler examination of the carotid arteries; a diameter reduction > 15% in at least one carotid artery was found in 26.7% of the sample. Clinical history and vascular risk factors were recorded, and the multifactorial analysis showed that age, history of hypertension and carotid bruit were the only significant predictive factors of carotid stenosis.

ISSN:1015-9770    

DOI:10.1159/000108810

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

Transient ischemic attacks (TIA) were observed in 17.5% of patients (40/227) before lacunar infarction (LI) in a consecutive clinical series. Approximately half of these patients (47.5%) had multiple episodes; most of them (89.5 %) were clinically stereotyped, and the median duration was 30 min. The average latency between the last episode and the LI was 24 h, and 72 h between the first episode and the LI. In comparison with TIA associated with ischemic infarctions in the middle cerebral-artery area (IMCA), TIA in LI presented (1) a lower frequency of episodes (17 versus 38%, p < 0.001); (2) a higher number of multiple episodes (47.5 versus 27%; p < 0.05); (3) a longer duration of neurological deficit (p < 0.002), and (4) a shorter latency between the last episode (p < 0.0001) or the first episode (p < 0.02) and the definitive ischemic stroke. Our results show that TIA associated with LI have some distinctive clinical features and some different semiological characteristics in comparison with TIA associated with IMCA.

ISSN:1015-9770    

DOI:10.1159/000108811

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

Using positron emission tomography (PET), the combined imaging of cerebral blood flow (CBF), cerebral blood volume (CBV), tissue oxygen tension (PtO2), oxygen extraction fraction (OEF), oxygen consumption (CMRO2) and glucose utilization (CMRglu) has allowed to demonstrate the 3 stages of hemodynamic compromise associated with acute arterial occlusion (1) autoregulation stage (hemodynamic reserve) with elevation of CBV; (2) oligemic stage (OEF reserve) with reduced CBF, elevated OEF and normal CMRO2, and (3) ischemic stage, with reduced CMR02 .and elevated CMRglu/CMRO2 ratio (anaerobic glycolysis). Sequential studies have demonstrated the transition from ischemia to tissue infarction, but also that from ischemia to eventual tissue integrity (penumbra ?); following the ischemic phase, the stage of reperfusion is well demonstrated by PET, as the luxury-perfusion syndrome. PET imaging of tissue pH has revealed that the initial stage of ischemic acidosis is followed by tissular alkalosis at reperfusion. PET has also demonstrated that functional impairment (hypometabolism) occurs at sites distant from that of ischemic injury, an effect that may partly underly the initial clinical expression of, and the ensuing functional recovery from, ischemic stroke.

ISSN:1015-9770    

DOI:10.1159/000108877

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

Regional blood flow and oxygen metabolism were determined by positron emission tomography using the steady-state technique with 150, in 2 patients with posthypoxic ischemic leukoencephalopathy, in 6 patients with leuko-araiosis and dementia, and in 6 patients with leuko-araiosis without dementia. Comparison between the three groups allowed us to conclude that leuko-araiosis is associated with a lowered cerebral blood flow, which is more pronounced and widespread in demented patients and more restricted to the white matter in nondemented ones.

ISSN:1015-9770    

DOI:10.1159/000108812

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

To evaluate the incidence of silent ischemic heart disease in cerebrovascular patients unable to exercise, we performed intravenous dipyridamole-thallium myocardial imaging in 38 consecutive patients with stroke without angina or previous myocardial infarction. Dipyridamole was injected intravenously at the dosage of 0.56 mg/kg over 4 min, followed by 4 min of handgrip exercise. Of the 38 patients, 35 had severe atherosclerotic lesions of the internal carotid artery and 3 occlusion of the middle cerebral artery. Dipyridamole-thallium myocardial imaging was normal in 15 patients and abnormal in 23 (60%): reversible perfusion defects were detected in 21 cases and fixed defects in 2. Minor side-effects were observed in 5 patients; no neurologic complications occurred. In conclusion, our findings suggest that in a large proportion of patients with severe large-artery occlusive cerebrovascular disease, a silent ischemic heart disease is present. Dipyridamole-thallium myocardial imaging can be proposed as a safe and valuable examination in the noninvasive cardiac screening of those cerebrovascular patients unable to exercise.

ISSN:1015-9770    

DOI:10.1159/000108813

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

As reported in the literature, the moderate ischemia zone characterized by a rapid restoration of spontaneous and evoked electrical activity following reperfusion (up to 2 h of ischemia) is ''fully reversible''. But returning to the normal conditions does not prevent selective neuronal death, probably influenced by excitatory neurotransmitters. On the basis of animal studies, it is argued that several hours of ‘ischemic penumbra’ will eventually increase the neuronal loss even with a restoration of electrical activity. We studied acute-stroke cases (blood partition coefficient between damaged and normal hemisphere) with single-photon emission tomography (SPECT) using 99mTc hexamethyl-propylamine oxime as a tracer for cerebral perfusion imaging. The limits of moderate ischemia (penumbra) associated with the tissue survival structure (CT scanning) are discussed. We aim to define, in the early stage of the disease, the ischemic threshold compatible with a thrombolytic therapy and no unacceptable hemorrhagic risk. Clinical recovery can roughly, but in a clinically relevant way, evaluate neuronal death in ischemic penumbra in hum

ISSN:1015-9770    

DOI:10.1159/000108878

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

Epidemiological studies provide major clues to etiology and therapeutic programs in stroke. Recent studies concerning secular trends in incidence and mortality, identification of well-defined independent risk factors and natural history of stroke are reviewed. While there has been a dramatic decline in stroke mortality (in relation to both declining incidence and improving survival following stroke) in most industrialized countries during the last two decades, data from Rochester show a recent increase in stroke incidence. Several factors could account for this new trend, including the availability of computed tomography with substantial improvement in stroke diagnosis. Arterial hypertension is the main risk factor for stroke, regardless of stroke mechanism. Recent analysis suggests that stroke incidence reduction could arise rapidly after hypertension control and that a lower blood pressure should confer a lower risk of vascular disease, even in individuals conventionally considered as ‘normotensive’: There is evidence that cigarette smoking is an important risk factor for stroke with an overall relative risk of 1.5. A cardiac condition may be a marker for another risk factor or the primary substrate for cerebral embolism. In patients with atrial fibrillation, the risk of stroke is increased through one or both of these mechanisms. The impact of alcohol, diabetes, cholesterol, fibrinogen, hormonal factors, asymptomatic carotid bruit and stenosis and transient ischemic attack on the risk of stroke is also discus

ISSN:1015-9770    

DOI:10.1159/000108879

出版商:S. Karger AG    

年代:1991

数据来源: Karger

摘要:

We studied 17 consecutive patients with nonaneurysmal cerebral hemorrhages larger than 55 cm3 to determine the computerized tomographic correlates of stupor and coma. Coma was associated with 8 mm or greater pineal displacement in 8 of 14 comatose patients. An extension of the clot that occupied or displaced the lower diencephalic region explained coma in the remaining 6 patients with less than 8 mm horizontal pineal displacement. All patients with diencephalic clot were comatose. Three initially drowsy or stuporous patients had 3 mm mean pineal displacement. Massive hydrocephalus occurred in 5 patients, always associated with diencephalic clot, and therefore never independently accounting for coma. Clot volume could be estimated from: volume (cm3) = [largest clot diameter (cm) X 14] – 14. We incidentally found that at least 6 of the 17 massive hemorrhages had progressed from smaller clot

ISSN:1015-9770    

DOI:10.1159/000108814

出版商:S. Karger AG    

年代:1991

数据来源: Karger