Showing papers in "Cerebrovascular Diseases in 1991"
TL;DR: The Scandinavian hemodilution study in acute ischemic stroke used the neurological scale presented here in assessing prognosis and long-term outcome.
Abstract: The Scandinavian hemodilution study in acute ischemic stroke used the neurological scale presented here in assessing prognosis and long-term outcome. The purpose of the present study was to test its i
332 citations
262 citations
TL;DR: Patients with acute cerebrovascular disorders with acute confusional states were studied in 155 consecutive representative patients, finding that patients who developed ACS were acutely confused on admission or developed ACS within 7 days of admission.
Abstract: Acute confusional states (ACS) were studied in 155 consecutive representative patients (mean age 73 years) with acute cerebrovascular disorders. Testing for ACS could be done in 94% of the patients. Sixty-nine of the 145 testable patients (48%) were acutely confused on admission or developed ACS within 7 days of admission. The mean age for the patients who developed ACS was 76 years compared with 69 years for patients without ACS (p
111 citations
TL;DR: One hundred cases of isolated angiopathy of the central nervous system (CNS) have been described, the majority of whom (71%) were diagnosed histologically, and the pathological findings were those of angi.
Abstract: 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 angi
83 citations
TL;DR: This work has reviewed the twelve prospective follow-up studies of angiographically documented symptomatic carotid artery occlusion in a total of 1,261 patients who were followed up over a mean period of 45 years.
Abstract: We have reviewed the twelve prospective follow-up studies of angiographically documented symptomatic carotid artery occlusion in a total of 1,261 patients who were followed up over a mean period of 45
83 citations
TL;DR: Considerable experimental evidence suggests that excessive stimulation of the N-methyl- D -aspartate (NMDA) receptor subclass of glutamate receptors plays a pivotal role in initiating NMDA-dependent cell reprograming in mice.
Abstract: Considerable experimental evidence suggests that excessive stimulation of the N-methyl- D -aspartate (NMDA) receptor subclass of glutamate receptors plays a pivotal role in initiating
59 citations
TL;DR: 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.
Abstract: 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.
58 citations
TL;DR: Patent foramen ovale (PFO) is present in 25-30% of the population and with activities implying a Valsalva maneuver, a transient right-to-left shunt occurs.
Abstract: Patent foramen ovale (PFO) is present in 25-30% of the population. Spontaneously, or with activities implying a Valsalva maneuver, a transient right-to-left shunt occurs. This can now be easily diagnosed with contrast echography. We report 29 cases of paradoxical cerebral embolism with a PFO and compare them with 25 reported cases. There may be clinical evidence suggesting the diagnosis: a Valsalva-inducing activity at the onset of stroke. previous chronic pulmonary hypertension, contemporary pulmonary embolism and evidence of deep vein thrombosis.
53 citations
TL;DR: A summary of animal experimental models for the production and treatment of global and regional cerebral ischemia and the methodological peculiarities of the various procedures are reviewed.
Abstract: A summary of animal experimental models for the production and treatment of global and regional cerebral ischemia is presented. The methodological peculiarities of the various procedures are reviewed
49 citations
TL;DR: 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 ofIschemia) is fully restored.
Abstract: 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 humans.
49 citations
TL;DR: 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).
Abstract: 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 rando
TL;DR: Measuring the infarction size with neuro-imaging after the early stage is a promising approach but procedure and device standardization are still limiting factors, especially for multicenter trials.
Abstract: The lack of efficacy proof explains that there is no standard therapy for acute stroke. If we consider the stroke incidence and the number of drugs tested and developed in this indication for more than 30 years, what are the difficulties to reach therapeutic efficacy? The first is patient selection: hemorrhage and ischemia are not candidates for the same therapy; for cerebral infarcts, therapeutic implications are often specific of the etiologic mechanism (arterial embolism, thrombosis with developed atheroma, hypertensive microangiopathy). The right selection depends oh clinical criteria for stroke diagnosis before any emergency strategy; on imaging criteria (computed tomography and magnetic resonance imaging) for more precise type, area and extension of cerebral damage, and on cerebrovascular criteria (Doppler, arteriography) for stroke mechanism. Hemodynamic and metabolic criteria are of great interest but have no direct application for therapeutic trials. The second difficulty is the assessment of therapeutic effect. Survival can be the main criteria only for severe strokes. Neurological recovery assessment is difficult and can be comparative only for similar patterns of deficits. Functional recovery assessment is possible with validated scales but is more sensitive to confusion factors. Measuring the infarction size with neuro-imaging after the early stage is a promising approach but procedure and device standardization are still limiting factors, especially for multicenter trials.
TL;DR: The development and generalization of CT or MRI in patients with acute stroke has allowed to refine the knowledge on the topography of cerebral infarcts, which was based on autopsy studies.
Abstract: The development and generalization of CT or MRI in patients with acute stroke has allowed to refine the knowledge on the topography of cerebral infarcts, which was based on autopsy studies. Still more
TL;DR: In 755 patients with acute stroke, blood pressure was followed throughout the hospital stay and showed a fast decline after admission, and patients with intracerebral hemorrhage had higher blood pressure.
Abstract: In 755 patients with acute stroke, blood pressure was followed throughout the hospital stay. The blood pressure showed a fast decline after admission. Patients with intracerebral hemorrhage had higher
TL;DR: Clinical predictors of leukoaraiosis were evaluated among patients admitted to a neurogeriatric ward and submitted to cranial computed tomography and were strongly correlated with increasi.
Abstract: We evaluated clinical predictors of leukoaraiosis among 218 patients admitted to a neurogeriatric ward and submitted to cranial computed tomography. Leukoaraiosis was strongly correlated with increasing age, also when this effect was adjusted for the other risk factor variables. Since lacunar infarcts were positively and nonlacunar negatively associated with leukoaraiosis, a history of stroke significantly predicted leukoaraiosis only when its effect was corrected for the infarct type. A complaint of gait disturbance and an extensor plantar response were the only significant predictors of leukoaraiosis among neurologic symptoms and signs in a multivariate model including the age and infarct type as covariates. Based on age and on these clinical features, the probability of encountering leukoaraiosis on the computed tomography scan of elderly neurological patients can be determined.
TL;DR: Fifteen healthy subjects were tilted at 70° from the horizontal during a period of 4 min while recording the Doppler signal from the middle cerebral artery to carry out digital signal analysis.
Abstract: Fifteen healthy subjects were tilted at 70° from the horizontal during a period of 4 min while recording the Doppler signal from the middle cerebral artery. Digital signal analysis carried out off-lin
TL;DR: Therapy of acute ischemic stroke includes general treatment, such as pulmonary function and airway protection, cardiac care and blood pressure management, fluid and electrolyte balance, and more.
Abstract: Currently, therapy of acute ischemic stroke includes general treatment, such as pulmonary function and airway protection, cardiac care and blood pressure management, fluid and electrolyte balance, tre
TL;DR: Intentional hemodilution has been shown to increase cerebral blood flow under normal conditions and in experimental stroke.
Abstract: Intentional hemodilution has been shown to increase cerebral blood flow under normal conditions and in experimental stroke. Clinical trials of hemodilution in patients with acute stroke have employed
TL;DR: Carotid PTA may be considered as a valid alternative to endarterectomy, at least in selected cases, and preliminary reports on percutaneous transluminal angioplasty of the internal carotid artery are promising.
Abstract: Preliminary reports on percutaneous transluminal angioplasty (PTA) of the internal carotid artery are promising. Our experience on 32 patients with symptomatic carotid stenoses is reviewed here. Successful dilation was obtained in 33 of 35 procedures, with an estimated patency rate of 85% at 1 year. In 3 cases, transient neurologic symptoms occurred within 2 days of angioplasty. Transient neck pain and bradycardia were the most commonly observed complications during carotid dilation. Carotid PTA may be considered as a valid alternative to endarterectomy, at least in selected cases.
TL;DR: Time between onset of deficit and start of treatment may be a critical factor in any acute stroke treatment and data are reported on delay in hospital admission in 120 patients in this prospective study.
Abstract: Time between onset of deficit and start of treatment may be a critical factor in any acute stroke treatment. In this prospective study, data are reported on delay in hospital admission in 120 consecut
TL;DR: The epidemiologic and clinical features in 180 patients with pure motor stroke and presumed lacunar infarct collected from a population-based stroke registry are determined.
Abstract: We determined the epidemiologic and clinical features in 180 patients with pure motor stroke (PMS) and presumed lacunar infarct (presumed lacunar PMS) collected from a population-based stroke registry
TL;DR: Small ''lacunar'' infarcts in the territory of the deep perforators (ITDP) have usually been attributed to small-vessel disease associated with hypertension or diabetes, but recently also to embolism.
Abstract: Small ''lacunar'' infarcts in the territory of the deep perforators (ITDP) have usually been attributed to small-vessel disease associated with hypertension or diabetes, but recently also to embolism
TL;DR: Eighteen patients were treated with 70 mg tissue plasminogen activator intravenously after the onset of acute severe cerebral ischemia: 10 suffered from vertebrobasilar occlusive disease and 8 received treatment with t-PA.
Abstract: Eighteen patients were treated with 70 mg tissue plasminogen activator (t-PA) intravenously after the onset of acute severe cerebral ischemia: 10 suffered from vertebrobasilar occlusive disease and 8
TL;DR: 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.
Abstract: Regional blood flow and oxygen metabolism were determined by positron emission tomography using the steady-state technique with O-15, 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.
TL;DR: Patients with anticoagulation-related intracerebral hemorrhage were most often noted as an additional factor causing the hemorrhage, and overall mortality was 50.
Abstract: We report a series of 40 patients with anticoagulation-related intracerebral hemorrhage. Minor head trauma was most often noted as an additional factor causing the hemorrhage. Overall mortality was 50
TL;DR: To evaluate the incidence of silent ischemic heart disease in cerebrovascular patients unable to exercise, intravenous dipyridamole-thallium myocardial imaging in 38 consecutive patients is performed.
Abstract: 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.
TL;DR: To analyze the factors that could influence early diagnosis and referral of subarachnoid hemorrhage, demographic, clinical and neuroradiological data of 112 cases of SAH admitted from January 19 are analyzed.
Abstract: To analyze the factors that could influence early diagnosis and referral of subarachnoid hemorrhage (SAH), demographic, clinical and neuroradiological data of 112 cases of SAH admitted from January 19
TL;DR: The problem of stroke of unknown origin is still unsolved and paradoxical embolism has been suggested as a possible cause.
Abstract: The problem of stroke of unknown origin is still unsolved. Since the report of the high prevalence of patent foramen ovale (PFO) in young stroke populations, paradoxical embolism has been suggested as
TL;DR: The association of stressful life events with stroke was examined in a prospective controlled study which included 84 consecutive stroke patients and a comparison group of 84 control cases.
Abstract: The association of stressful life events with stroke was examined in a prospective controlled study which included 84 consecutive stroke patients and a comparison group of 84 control cases. The result
TL;DR: Magnetic stimulation was performed on 22 patients with acute stroke, only 1 patient had a prolonged motor conduction time (MCT); this was associated with a poor recovery.
Abstract: Magnetic stimulation was performed on 22 patients with acute stroke, Only 1 patient had a prolonged motor conduction time (MCT); this was associated with a poor recovery. In 11 patients, motor evoked