摘要:

Abstract not available.

ISSN:0039-2499    

出版商:OVID    

年代:1983

数据来源: OVID

摘要:

In order to relate clinical, angiologic and brain-morphological findings, 107 patients with internal carotid artery occlusion were examined clinically and by Doppler sonography, computerized tomography and cerebral angiography. During computerized tomography, haemodynamically induced infarctions could be differentiated from those, caused by periocclusive embolism towards the major brain arteries. This differentiation was based on an integration of angiological as well as brain-morphological data and implicates some important diagnostic, therapeutic and prognostic consequences. The first group may benefit from immediate surgical restoration of carotid blood flow and have a relatively good prognosis. By contrast, subjects presenting territorial infarctions mostly experience severe and permanent neurological deficits. They should not undergo revascularization since endarterectomy increases the risk of cerebral hemorrhage but cannot cause clinical improvement. In five patients, following special angiographic techniques, the lesions of the internal carotid artery turned out to be pseudoocclusions. This condition threatens the patient considerably but is well accessible to surgical reconstruction. Thus, pseudooclusion seems to be one of the most convincing indication for emergency endarterectomy of the internal carotid artery.

ISSN:0039-2499    

出版商:OVID    

年代:1983

数据来源: OVID

摘要:

The present study was designed to clarify the relationship of cerebral blood flow (CBF) to blood-brain barrier (BBB) in the ischemic brains with or without recirculation, which were produced by clipping of both common carotid arteries in spontaneously hypertensive rats. CBF was measured by the hydrogen clearance method and BBB function was evaluated by the permeability of 131I-albumin and Evans blue dye. Cortical CBF was reduced from 48.8 +/− 9.5 to 4.0 +/− 1.2 ml/100 gm/min during 1 hr ischemia and further to 2.6 +/− 0.3 ml/100 gm/min during 3 hrs ischemia, while thalamic CBF was reduced much less from 50.0 +/− 3.6 to 17.9 +/− 6.5 ml/100 gm/min and to 17.5 +/− 11.0 ml/100 gm/min, respectively. There was no increase in permeability to protein tracers observed in such 1 hr or 3 hrs ischemic brain. Both cortical and thalamic CBF were markedly increased 2.5 to 6 fold of resting values at 5 min after recirculation in the 1 hr ischemic brain. In the 3 hrs ischemic brain, however, both CBF were only slightly increased but never restored to the resting level even at 30 min after recirculation. In such reperfused brains, exudation to Evans blue dye was observed in none of 16 animals with 1 hr ischemia, but in 18 of 23 with 3 hrs ischemia. Disruption of BBB was twice more frequent in the cortex (77.8%) than in either thalamus (33.3%) or hippocampus (33.3%). Permeability index of 131I-albumin (brain albumin/blood albumin) was significantly higher in the ischemic areas stained with blue dye (2.07 +/− 0.45%) than in non-ischemic control brain (0.10 +/− 0.01%).(ABSTRACT TRUNCATED AT 250 WORDS)

ISSN:0039-2499    

出版商:OVID    

年代:1983

数据来源: OVID

摘要:

It is generally stated that ulceration of the carotid bifurcation plaque may give rise to embolization and symptoms of cerebral ischemia. It has been suggested that prophylactic carotid endarterectomy is indicated in asymptomatic patients if the angiogram is interpreted as showing ulceration. We therefore determined the accuracy of the radiologic diagnosis of ulceration by comparing the radiologic and morphologic findings in 155 carotid endarterectomies. Ulceration was diagnosed in 54% of the angiograms and 47% of the surgical specimens and was not related to the degree of stenosis. Angiography had a sensitivity of 73%, a specificity of 62% and an overall accuracy of 67%. For the non-flow-restrictive lesions these figures were 65%, 66%, and 66%. If surgery were based on the angiographic diagnosis of ulceration in plaques with less than 50% stenosis, 16 out of 42 operations (38%) would have been done unnecessarily. Variability of the angiographic diagnosis of ulceration is also shown by a high interobserver variability; two sets of two authors read the angiograms independently and disagreed in 24% of the cases. The decision to operate should not depend entirely upon the angiographic diagnosis of ulceration.

ISSN:0039-2499    

出版商:OVID    

年代:1983

数据来源: OVID

摘要:

One hundred twenty eight cervical carotid arteriograms were twice viewed by three readers for the evaluation of atherosclerotic disease at the carotid bifurcation. Stenoses were estimated using calipers to the nearest 5% and lesions were qualitatively characterized as smooth, irregular, or ulcerated. The intraobserver correlation coefficient between estimates of percent stenosis was .94 overall and .98 for the internal carotid artery. The average intraobserver variability in estimating percent stenosis was 5.23% for all vessels and 6.04% with a standard deviation of 8.09% for the internal carotid artery. The intraobserver percent agreement at a fixed stenosis is defined as the percent of the time one reader on two readings would read at least the fixed percent stenosis among cases that might be read as having the fixed percent stenosis. The intraobserver percent agreement rate for the internal carotid artery was 95.9% at greater than 0% stenosis, 90.4% for 50% or greater stenosis, and 96.8% for 100% stenosis (total occlusion). The interobserver correlation coefficient between readers was .92 overall and .97 for the internal carotid artery. The absolute difference in percent stenosis between readers was 7.21% for all vessels and 8.64% for the internal carotid artery with a standard deviation of 9.5%. The interobserver agreement rate for the internal carotid artery at greater than 0% stenosis was 93.0%, 85.4% for 50% or greater stenosis and 96.8% at 100% stenosis. The addition of oblique views had no statistical effect on estimates of percent stenosis but increased the frequency with which irregularity and ulceration were diagnosed in the internal carotid artery.

ISSN:0039-2499    

出版商:OVID    

年代:1983

数据来源: OVID

摘要:

Eighteen consecutive patients satisfying predefined clinical criteria for embolic strokes were prospectively studied by sequential computerized tomography (CT). Their findings were compared to CT scans obtained from patients presumed to have suffered thrombotic strokes. Our data reveal that the CT appearance of hemorrhagic infarction is likely to occur twice as frequently (22%) in CT scans of strokes presumed embolic than in those presumed thrombotic, where hemorrhagic infarction appeared at some time in 10% of the patients. No patient deteriorated with anticoagulation regardless of the CT appearance. In patients showing hemorrhagic infarction before anticoagulants, follow-up scans obtained after the administration of anticoagulants revealed resolution of the hemorrhagic aspect.

ISSN:0039-2499    

出版商:OVID    

年代:1983

数据来源: OVID

摘要:

Forty-seven patients with ICA occlusion and who presented either without any or only a mild neurological deficit were prospectively followed for an average of 34.4 months. During this period of time, 11 patients (23.5%) suffered a cerebral infarction of which two-thirds were ipsilateral to the occluded artery. The stroke rate distal to an occluded ICA artery was 5% per year. Twenty-four patients (51%) continued to experience TIA's in the territory of the occluded artery. The mortality rate was low (8.5%) during follow-up. Whether extracranial-intracranial bypass surgery will decrease the risk of cerebral infarction in this subgroup of patients is unknown. The International EC/IC Collaborative Trial may elucidate this point because this subgroup represents one of the randomization strata of that study.

ISSN:0039-2499    

出版商:OVID    

年代:1983

数据来源: OVID

摘要:

Cerebral blood flow CBF was studied in 14 patients with transient ischemic attacks TIA and arteriosclerotic neck vessel disease. CBF was measured by a rapidly rotating single photon emission computerized tomograph using Xenon-133 inhalation. This method yields images of 3 brain slices depicting CBF with a spatial resolution of 1.7 cm. Based primarily on the clinical evidence and on the angiographical findings embolism was considered the pathogenetic factor in 10 cases, whereas chronic hemodynamic insufficiency rendered symptomatic by postural factors probably accounted for the symptoms in 4 patients. Of the 14 patients, all studied days to weeks after the most recent TIA, four showed hypoperfused areas on the CBF-tomograms and with roughly the same location hypodense areas on CT-scanning, i.e. areas of complete infarction. However, an additional five patients showed reduction of CBF in areas with no abnormality on the CT-scan. The abnormal blood flow pattern was found to be unchanged after clinically successful reconstructive vascular surgery. This suggests the presence of irreversible ischemic tissue damage without gross emollition (incomplete infarction). It is concluded, that TIAs are often harmful events, as no less than 9 of the 14 patients studied had evidence of complete and/or incomplete infarction. Thorough examination and rational therapy should be instituted as soon as possible to prevent further ischemic lesions.

ISSN:0039-2499    

出版商:OVID    

年代:1983

数据来源: OVID

摘要:

We studied 8 patients with cerebral infarction in the deep territory of the middle cerebral artery (MCA). All patients had a definite cardiac source of emboli and no known factors for thrombosis. Mixed sensory and motor deficit was found in all but one patient and CT scan showed larger lesions than usually reported in lacunar infarcts. Contrast enhancement was seen in all cases in which CT scan was performed in the second or third week. It is concluded that embolic infarcts in deep cerebral territory of MCA from a cardiac source are more frequent than previously reported. This diagnosis has to be considered when CT scan demonstrates a deep cerebral infarct.

ISSN:0039-2499    

出版商:OVID    

年代:1983

数据来源: OVID

摘要:

The clinical and pathologic findings in eleven patients with fatal cerebral hemorrhages related to cerebral amyloid angiopathy (CAA) are described. The hemorrhages were bihemispheric, though not necessarily of simultaneous onset in four patients, and favoured the fronto-parietal cortex and white matter in ten patients. Dissection into the subarachnoid space was common. Cerebrovascular lesions or cardiomegaly related to hypertension coexisted with those of CAA in three cases. Seven patients were not demented prior to the ictus. Ten of eleven brains contained abundant senile plaques and/or neurofibrillary tangles, whether or not the patient had been clinically demented. In the elderly, CAA is an important etiologic consideration for cerebral hemorrhage, especially if the hemorrhage occurs in a peripheral location in the brain and is superimposed on a history of dementia.

ISSN:0039-2499    

出版商:OVID    

年代:1983

数据来源: OVID