bluuebunny/crossref_metadata_2025 huggingface dataset:
The decline of stroke.
Authors: Whisnant J P
Published: June 2011

Stroke mortality in the United States has declined since 1900. The mortality rates from stroke in Rochester, Minnesota, have declined 76% since 1950, and the primary cause for the declines is a decrease in the incidence of new cases of cerebral infarction and cerebral hemorrhage. There are no data on the incidence of stroke prior to 1945 to confirm the US mortality trend. The decline in incidence was noted in women 10-15 years before it was seen in men. Hypertension is the most important risk factor for stroke. Hypertension surveys have shown an increasing effectiveness of antihypertensive medication in lowering blood pressure, and the effect was noted earlier in women. Available evidence is consistent with the idea that treatment of hypertension is the only significant contributor to the decline of stroke.
Transient changes in cerebral vascular resistance during the Valsalva maneuver in man.
Authors: Greenfield J C , Rembert J C , Tindall G T
Published: June 2011

Measurements of cerebral spinal fluid pressure, arterial pressure, and internal carotid artery blood flow were obtained in a series of patients during a Valsalva maneuver. During straining (phase II), an 11% reduction in mean arterial pressure was associated with a 21% decrease in internal carotid flow from control values; and following release (phase IV), the 19% increase in mean arterial pressure produced a 22% increase in internal carotid artery flow. Perfusion pressure computed as the mean arterial pressure minus cerebral spinal fluid pressure and internal carotid artery blood flow were used to calculate an index of cerebral vascular resistance. The data indicate that a modest but significant decrease in vascular resistance occurred during phases II and III followed by return to control levels during phase IV. These changes in vascular resistance were not rapid enough or of sufficient magnitude to maintain constant cerebral perfusion during the Valsalva maneuver.
Declining incidence and mortality of stroke?
Authors: Kotila M
Published: June 2011

The incidence and mortality from stroke in Espoo-Kauniainen, Finland, in 1972-73 were compared to the incidence and mortality from stroke in the same area 1978-80. The factors at the acute stage influencing case fatality were also analyzed. A declining trend in age-adjusted incidence of stroke was observed, though failing to reach statistical significance. The greatest decline was seen in the incidence of cerebral hemorrhage in men, with a statistically significant difference. The incidence of subarachnoid hemorrhage also decreased, and in women the decline was significant. There was no decrease at all of the incidence of cerebral infarction. The total mortality displayed no clear declining trend. However, the mortality from cerebral hemorrhage after three months from stroke had gone down from 72% to 59%. The most important factors responsible for increased case fatality were: lowered level of consciousness, cerebral hemorrhage and old age. The case fatality was also higher for women than for men. Previous heart diseases increased the mortality, but hypertension, diabetes, pure myocardial infarction and previous transient ischaemic attacks had no influence on mortality. The cause of decline in the incidence of cerebral hemorrhage might be improved care of hypertension: the decline in the incidence of subarachnoid hemorrhage however remains unclear.
Vertebral artery stenosis: long-term follow-up.
Authors: Moufarrij N A , Little J R , Furlan A J , Williams G , Marzewski D J
Published: June 2011

Ninety-six patients with greater than or equal to 50% unilateral vertebral artery (VA) stenosis were followed up for an average of 4.6 years. In 89 patients (93%) at least one VA origin was involved, while the intracranial VA was affected in 3 patients (3%). Seventy-four patients (77%) had greater than or equal to 50% stenosis of at least one internal carotid artery, of whom 52 underwent carotid endarterectomy. None of the patients had definite vertebrobasilar transient ischemic attacks (VB TIA). Nineteen patients (19.8%) experienced non-localizing symptoms possibly compatible with VB TIA, none of whom had a stroke. Twenty-three patients (24%) had strokes. The only two patients (2%) who sustained a brainstem infarction had fatal strokes and both were known to have basilar artery stenosis in addition to their VA stenosis. The observed stroke rate was 8.5 times the expected infarction rate for a normal population. Forty patients died during follow up. The observed 5-year survival rate was 60% compared to 87% in a matched normal population. Eight deaths (20% of all deaths) were caused by stroke and 21 deaths (52.5% of all deaths) were cardiac related. VA stenosis is most frequently located at the VA origin (93%), and is associated with a low incidence of brainstem infarction.
The prognostic value of the CT scan in conservatively treated patients with intracerebral hematoma.
Authors: Steiner I , Gomori J M , Melamed E
Published: June 2011

Prognostic factors for survival and neurological recovery were assessed in 42 patients with nontraumatic intracerebral hematoma (ICH) diagnosed by CT scan. None underwent surgical evacuation of hematoma. CT scans were used to determine location and volume of ICH and presence or absence of intraventricular hemorrhage (IVH). Only 11 patients (26%) died and 17 patients (40.5%) recovered fully. Mortality was associated with: 1) loss of consciousness as a presenting symptom (63.5% mortality rate versus 13% when there was no loss of consciousness at the onset; p less than 0.01). 2) extension of the bleeding into the ventricular system (45% mortality rate versus 9% when hemorrhages were confined to brain parenchyma; p less than 0.01). 3) location of hematoma in the posterior fossa (mortality rate of 43% versus 23% for intrahemispheric hematomas). Mortality was unaffected by age of patients and size of ICH. Full neurological and functional recovery occurred mainly when estimated volume of hematomas was less than 15 cc and with lobar hematomas regardless of size. In survivors there is CT evidence of complete resolution of ICH. Our data indicates a favourable outcome in a relatively large percentage of patients with ICH treated conservatively and therefore questions the need for surgical evacuation of hematoma.
Age-matched normal values and topographic maps for regional cerebral blood flow measurements by Xe-133 inhalation.
Authors: Matsuda H , Maeda T , Yamada M , Gui L X , Tonami N , Hisada K
Published: June 2011

The relationship between normal aging and regional cerebral blood flow (rCBF) computed as initial slope index (ISI) by Fourier method was investigated in 105 right-handed healthy volunteers (132 measurements) by Xe-133 inhalation method, and age-matched normal values were calculated. Mean brain ISI values showed significant negative correlation with advancing age (r = 0.70, p less than 0.001), and the regression line and its 95% confidence interval was Y = -0.32 (X - 19) + 63.5 +/- 11.2 (19 less than or equal to X less than or equal to 80). Regional ISI values also showed significant negative correlations for the entire brain (p less than 0.001). The regional reductions of ISI values with advancing age were significantly greater in the regional distribution of the middle cerebral arteries bilaterally, compared with regions in the distribution of the other arteries (p less than 0.05). Therefore, measured rCBF values for patients must be compared to age-matched normal values for mean hemispheric and each region examined. Two kinds of topographic maps, brain map showing rCBF compared to age-matched normal values and showing hemispheric differences were made by dividing patient's values by the 95% confidence limits for age-matched normal values and displaying laterality index calculated as follows, respectively. (formula; see text) These maps were useful for evaluating significantly decreased or increased regions and regional hemispheric differences.
Ataxic-hemiparesis, localization and clinical features.
Authors: Huang C Y , Lui F S
Published: June 2011

Five additional cases of ataxic-hemiparesis are reported. In 3 cases, computed tomography showed an area of decreased attenuation in the posterior limb of the internal capsule, and in 1 case, 2 areas of attenuation in the corona radiata. A review of previously reported cases suggest that brainstem ataxic-hemiparesis may be separated from supratentorial forms of ataxic-hemiparesis by the presence of nystagmus, dysarthria, cranial neuropathy, and the absence of sensory abnormality.
Neuropsychological performance one week after carotid endarterectomy reflects intra-operative ischemia.
Authors: Brinkman S D , Braun P , Ganji S , Morrell R M , Jacobs L A
Published: June 2011

Fourteen patients with severe bilateral carotid artery stenosis underwent carotid endarterectomy. Intra-operative ischemia was monitored by somatosensory evoked potentials (SSEP) bilaterally. Neuropsychological evaluations were completed within two days before operation and 4-9 days after operation. Complete loss of N1-P1 or P1-N2 components of the SSEP (seen in 4 patients) was associated with a worsening of neuropsychological abilities (p less than .01). Two of these patients subsequently had strokes (7 and 35 days after operation). No other patients in the series have had strokes. Patients whose N1-P1 or P1-N2 amplitudes decreased by 50% or more performed worse after operation than patients with less severe reductions in these amplitudes (p less than .02). Time since first ischemic symptoms, age, education, clamp time, pre-operative stroke, and interval from surgery to assessment were not statistically related to changes in neuropsychological abilities. Patients with ischemic events in the week prior to surgery tended to improve in neuropsychological abilities 4-9 days after operation (p less than .05). Recentness of ischemic episode, however, was not related to intra-operative SSEP change. Results suggest the potential utility of intra-operative SSEP monitoring and early post-operative neuropsychological assessments both for clinical and research purposes.
The value of histopathological examination of surgically removed blood clot in determining the etiology of spontaneous intracerebral hemorrhage.
Authors: Hinton D R , Dolan E , Sima A A
Published: June 2011

The surgical specimens from all evacuated spontaneous intracerebral and intracerebellar hemorrhages at the Toronto General Hospital from 1976 to 1981 were reviewed. Cases resulting from trauma or from pre-operatively diagnosed aneurysms or arteriovenous malformations were excluded, leaving 84 cases in which the etiology was unknown. Seventy-five of the cases were intracerebral hemorrhages, while 6 were intracerebellar and 3 were intraventricular. Brain tissue was received with the blood clot in 54 cases (64%). From this tissue, an anatomic diagnosis was made in 37 cases; and in 14, the specific etiology of the hemorrhage could be determined. The specific etiologic diagnoses were tumor (7), amyloid angiopathy (6) and abscess (1). In 4 other cases, vasculopathy associated with hypertension was suggested as a possible etiologic diagnosis. The high incidence of a specific etiologic diagnosis made from specimens in which tissue was included (25%) suggests that biopsy of adjacent brain tissue or preservation of tissue fragments identified at the time of surgery is of diagnostic value.
Behavioral performance of rats following transient forebrain ischemia.
Authors: Volpe B T , Pulsinelli W A , Tribuna J , Davis H P
Published: June 2011

Rats subjected to transient forebrain ischemic injury by the method of four vessel occlusion (4-VO) develop irreversible injury to select populations of vulnerable neurons which include pyramidal cells in the CA-1 region of the hippocampus. This brain area is thought to be crucial for learning and memory. Rats subjected to 30 minutes of 4-VO, and then cerebral reperfusion were tested on a radial 8-arm maze task after they had recovered. The data shows that both 4-VO and control animals improve their performance over trials, but that 4-VO rats are impaired on "working" and "reference" tasks. The data suggest that 4-VO rats' impaired "working" performance is permanent, compared to their transient "reference" impairment. Alterations in sensorimotor activity could not account for these performance deficits since control and 4-VO rats demonstrated equivalent choice time per maze arm. Performance deficits in rats following forebrain ischemic injury may be similar to some of the cognitive deficits found in humans survivors of cerebral hypoxia-ischemia.
The natural history of carotid arterial disease in asymptomatic patients with cervical bruits.
Authors: Roederer G O , Langlois Y E , Jager K A , Primozich J F , Beach K W , Phillips D J , Strandness D E
Published: June 2011

A prospective study was initiated in January 1980 to follow with Duplex scanning a consecutive series of 167 asymptomatic patients with cervical bruits. Patients were seen at six month intervals for the first year and yearly thereafter. Based on previously validated criteria, disease at the carotid bifurcation was classified into 6 categories: Normal, 1-15% diameter reduction, 16-49%, 50-79%, 80-99%, and occlusion. Patients were evaluated to assess: the occurrence of new neurological symptoms, the stability of the lesions at the carotid bifurcation, and the possible role of risk indicators on disease changes. During follow-up, ten patients became symptomatic (6 with TIA's and 4 with stroke). The development of symptoms was accompanied by disease progression in 8 patients. By life table analysis, the annual rate occurrence of symptoms was 4%. The mean annual rate of disease progression to a greater than 50% stenosis was 8%. When progression in all categories was considered, 60% of the sides showed some disease aggravation. The presence of or progression to a greater than 80% stenosis was highly correlated (p = 0.00001) with either the development of a total occlusion of the internal carotid artery or new symptoms. The major risk factors associated with disease progression were cigarette smoking, diabetes mellitus, and age. Those patients under 65 years of age were most likely to show progression. Despite high rates of disease progression, this study further supports the contention that it is prudent to follow a conservative course in the management of asymptomatic patients presenting with a cervical bruit.(ABSTRACT TRUNCATED AT 250 WORDS)
Naloxone therapy during focal cerebral ischemia evaluation in a primate model.
Authors: Zabramski J M , Spetzler R F , Selman W R , Roessmann U R , Hershey L A , Crumrine R C , Macko R
Published: June 2011

Conflicting reports have appeared in the literature regarding the effect of the opiate antagonist naloxone on ischemic neurologic deficits. We report the results of a study using naloxone in our model of focal cerebral ischemia in the awake primate. A total of 14 adult baboons were subjected to six-hour occlusion of the left middle cerebral artery (MCA). Seven animals served as controls and seven received treatment with naloxone (5 mg/kg) beginning 30 min after MCA occlusion and continuing until two hours after reperfusion. All animals developed profound hemiparesis and homonymous hemianopsia within seconds of inflating the MCA occluder. Acutely, therapy with naloxone partially reversed ischemic neurologic deficits in five of the seven treatment animals. Within minutes of receiving the loading dose of naloxone, responding animals were more alert and demonstrated improvements in motor function. Naloxone did not affect mortality: Three animals in the treatment group and two in the naloxone group died secondary to malignant intracranial pressure within 48 hours of the ischemic episode. In animals surviving the ischemic insult however, treatment with naloxone significantly improved neurologic outcome at 10 days (p less than 0.05). Neuropathologic examinations in these animals revealed amelioration of ischemic tissue damage, with three of the five suffering only small focal areas of infarction. (All control animals suffered large infarcts of the MCA territory.) Our results verify that naloxone can reverse ischemic deficits, and more importantly may improve the outcome from focal ischemic insults.
The CO2 response in focal cerebral ischemia--sequential changes following recirculation.
Authors: Seki H , Yoshimoto T , Ogawa A , Suzuki J
Published: June 2011

The study was undertaken to determine the effects of various levels of ischemia on the CO2 response and on the development of infarction using the canine thalamic infarction model. Three groups were studied: those with severe ischemia (rCBF below 40% of the pre-occlusion levels), moderate ischemia (between 40% and 70%) and mild ischemia (greater than 70%). The CO2 response was measured after 30 minutes, 1, 2 and 6 hours of occlusion and then for 4 hours after recirculation. The CO2 response recovered after 30 minutes of occlusion in the severely ischemic animals, but in 8 of the 9 animals with 1 or more hours of occlusion, an impaired CO2 reactivity was found during occlusion and during recirculation. Among moderately ischemic animals, many showed impaired CO2 reactivity during occlusion, but following recirculation no single trend was observed. Among mildly ischemic animals, almost no abnormalities in the CO2 response were seen either during 6 hours of occlusion or thereafter. Among the 11 animals from all 3 groups which showed impaired CO2 reactivity, 10 developed infarction, while among the 10 animals which showed no impaired CO2 reactivity, in 9 infarction did not arise.
Cerebral infarction after middle cerebral artery occlusion in progenies of spontaneously stroke-prone and normal rats.
Authors: Coyle P , Odenheimer D J , Sing C F
Published: June 2011

A differential outcome results from rapid middle cerebral artery (MCA) occlusion in young normotensive Wistar (NW) rats as compared to the spontaneously hypertensive stroke-prone (SHRSP) rat. The SHRSP invariably infarcts; the NW usually does not. To determine if segregation at a single autosomal locus explains the difference between strains, a NW male was crossed with several SHRSP females to produce F1 rats. The segregation of the strain difference was studied in the F2 and backcrosses to the NW and SHRSP parental strains. The relative frequency of infarcting and noninfarcting animals in the segregating progenies supported a single locus recessive model of inheritance for susceptibility to infarction after sudden occlusion of the MCA. Mean infarct size was largest for SHRSP and proportional to the SHRSP gene dosage in the segregating progenies. Variation in the size of the infarct within segregating classes may be attributable to the segregation of polygenes and/or environmental influences during the initial formation of the cerebral anastomoses.
Ischemic cerebrovascular disease in the young. Two common causes in India.
Authors: Srinivasan K
Published: June 2011

Mandurai City is a composite of many villages with a total population not exceeding one million. Undoubtedly more than 95% of the hospital patients come from the rural areas. Our Government Hospital is the largest and reflects the medical assistance provided for people of average and low income. In our experience, 15% of cerebrovascular strokes occur in those below 40 years of age. Meningovascular neurosyphilis in men (10-15%) and puerperal cerebral venous thrombosis in women (20%) were the two commonly proved causes. Haemorrhagic stroke was uncommon. Embolic strokes from rheumatic heart disease formed 10%. In over 50%, the cause of stroke was not clear. Among 150 patients with neurosyphilis, mostly men, 25 had cerebral arterial thrombosis with stroke syndrome. This study reports on 138 patients with cerebral venous thrombosis and 7 patients with arterial thrombosis in puerperium. Mortality was 20% and quality of survival was good. The incidence, clinical picture, and diagnostic investigations are discussed with a review of literature.
Selective thromboxane inhibition: a new approach to antiplatelet therapy.
Authors: Fisher M , Weiner B , Ockene I S , Hoogasian J S , Natale A M , Arsenault J R , Johnson M H , Levine P H
Published: June 2011

Antiplatelet drugs as exemplified by aspirin are used frequently to prevent stroke. Aspirin inhibits the formation of both the potent platelet aggregator, thromboxane A2 and the potent anti-aggregator, prostacyclin. Another approach to the inhibition of platelet aggregation might involve selective suppression of thromboxane formation. We report our experience in swine with UK-38,485, a drug which selectively inhibits thromboxane formation. The rationale and potential uses of UK-38,485 in the in vivo prevention of platelet aggregation and for the therapy of cerebrovascular disease are discussed.
A randomized trial of team care following stroke.
Authors: Wood-Dauphinee S , Shapiro S , Bass E , Fletcher C , Georges P , Hensby V , Mendelsohn B
Published: June 2011

A randomized controlled trial was conducted to examine the effects of interdisciplinary team care on acute hospitalized stroke patients. After obtaining baseline information on 42 stroke victims receiving conventional care in a general hospital, 130 stroke patients were stratified and randomly assigned either to Traditional or Team care. Assessments by independent evaluators permitted comparisons between Team and Traditional groups with reference to patient survival, motor performance and functional abilities. Data obtained prospectively from charts and treatment logs allowed the care process across groups to be compared. Results demonstrated that Team and Traditional patients fared similarly in survival. However there was an unexpected difference in survival depending upon sex. For motor performance, male survivors performed better with Team care and female survivors with the Traditional method. In terms of functional abilities, male patients receiving Team care again performed better than their Traditional counterparts, whereas in women there was no difference between the treatment groups.
The terminology of transient visual loss due to vascular insufficiency.
Authors: Hedges T R
Published: June 2011

Transient visual loss due to cerebro-ocular vascular disease is a common symptom. The purpose of this paper is to present a unified terminology of the monocular vs. binocular or homonymous types. Lack of proper identification may lead to mis-diagnosis and improper management of these entities. Monocular blurred vision must be investigated since its origin is so commonly due to atherosclerosis of the carotid system. Binocular blurred vision due to vertebro-basilar insufficiency is managed conservatively in almost all instances.
Headache in cerebrovascular disease.
Authors: Portenoy R K , Abissi C J , Lipton R B , Berger A R , Mebler M F , Baglivo J , Solomon S
Published: June 2011

Two hundred fifteen consecutive patients with cerebrovascular events were evaluated prospectively for the incidence and characteristics of headache. Of 163 patients able to communicate, headache occurred in 29% with bland infarcts, 57% with parenchymal hemorrhage, 36% with transient ischemic attacks and 17% with lacunar infarcts. Patients with a history of recurrent throbbing headache were significantly more likely to have headache, usually throbbing in quality, during the present illness. Women developed headache significantly more often than men. Headache began prior to the vascular event in 60% of patients and at its onset in 25%. The quality, onset and duration of the headache varied widely among patients. Headache in cerebrovascular disease is common, though neither its occurrence nor characteristics predict lesion type or location. Though the pathogenesis of the headache is unknown, its association with prior throbbing headache suggests that similar factors may operate in both.
Cell density and cortex thickness in the border zone surrounding old infarcts in the human brain.
Authors: Nedergaard M , Astrup J , Klinken L
Published: June 2011

Six cases of completed ischemic stroke in the middle cerebral artery territory of more than two months' duration were selected for this study of neuropathology. Coronal brain slices of the entire brain were cut for histology and stained with Klüver-Barrera's stain. Neuronal and glial cell density, and cortex thickness were measured at various distances from the border of the infarct. Corresponding counting points in the contralateral hemisphere served as control in all cases. The density of histologically intact neurons was in all cases normal at a distance of 0.5 cm or more from the border of the infarcts. In one half of the cases the border zone between infarcted and normal tissue was less than a few cells in thickness. This study of old brain infarcts confirms the commonly held view that there is an abrupt transition between infarcted and normal tissue. This observation suggests that the wide zone of low blood flow and metabolism surrounding cerebral infarcts is not caused by selective loss of neurons. Instead, we hypothesize that such change in blood flow and metabolism is the result of neuronal disconnection and cortical deactivation.
Intravertebral artery adenosine fails to alter cerebral blood flow in the dog.
Authors: Boarini D J , Kassell N F , Sprowell J A , Olin J
Published: June 2011

The effect of intra-arterial adenosine on cerebral blood flow was studied in 11 anesthetized dogs. In a first group of 6 dogs, adenosine was infused into a vertebral artery for 40 minutes at a dose of 0.3 to 0.5 mg/kg/min. Blood flow was determined before, during and after the adenosine infusion using the radioactive microsphere technique. In a second group of 5 dogs, adenosine (3 +/- 1 mcg/kg/min) was infused in a similar manner after potentiating its effect with intravenous dipyridamole, and measurements before and after the intravenous dipyridamole and during and after the adenosine infusion were performed. Systemic arterial pressure and blood gases were unchanged throughout the experiment in both groups of dogs. Blood flow to the cerebral hemispheres, cerebellum, brain stem, paraspinous and temporalis muscles remained unchanged during the adenosine infusion in both groups of dogs. Adenosine has been implicated as an active agent in the vasodilatory component of cerebral autoregulation. A controversy exists as to whether intervascular or only interstitial adenosine is of physiologic importance. These findings suggest that intra-arterial adenosine does not play a significant role in the regulation of cerebral blood flow.
The rationale for patch-graft angioplasty after carotid endarterectomy: early and long-term follow-up.
Authors: Deriu G P , Ballotta E , Bonavina L , Grego F , Alvino S , Franceschi L , Meneghetti G , Saia A
Published: June 2011

A prospective study was undertaken in March 1980, at the Vascular Surgery Department of the Padua University, Medical School, to establish whether patch graft angioplasty is useful in preventing restenosis after carotid endarterectomy (CE). Seventy-four patients underwent 86 CE (bilateral in 12 cases) for atherosclerotic disease involving the carotid bifurcation. Thirty-eight (51.4%) patients presented TIA's or non hemispheric symptoms of cerebrovascular insufficiency; 30 (40.5%) were asymptomatic and 6 (8.1%) had partial nonprogressing or fixed strokes. All operations were performed under general anesthesia, with pharmacologic hypertension and systemic heparinization; in all cases, continuous EEG monitoring and 'stump pressure' measurement were employed. The operation was performed without a temporary intraluminal shunt in the patients showing tolerance to carotid clamping. The protection of the shunt was required only in patients with EEG monitoring changes (17). All carotid arteriotomies were extended into the internal carotid artery to overpass the end of the endarterectomy. Overpass was also used in the proximal edge of the arteriotomy, in the common carotid artery. The distal intima was never fixed with stitches and the arteriotomy was routinely closed with a PTFE patch graft angioplasty. Early results of cerebral protection were excellent. No patient presented permanent or transient postoperative neurological problems and no patient died in the postoperative period for causes related to the operation. This is substantiated by results we achieved during the period 1970-1979 in 192 patients, when all carotid endarterectomies were routinely performed without a shunt, with figures of 2.5% of postoperative stroke and 1.5% of mortality. Longterm follow-up (from 6 to 36 months) was completed in 51 patients (60 operations).(ABSTRACT TRUNCATED AT 250 WORDS)
Ischemic brain edema following occlusion of the middle cerebral artery in the rat. I: The time courses of the brain water, sodium and potassium contents and blood-brain barrier permeability to 125I-albumin.
Authors: Gotoh O , Asano T , Koide T , Takakura K
Published: June 2011

The present study was undertaken to analyze the roles of brain cations and of the blood-brain barrier (BBB) to albumin in the development of ischemic brain edema. Using the rat middle cerebral artery (MCA) occlusion model, changes in the brain water, sodium, and potassium contents were followed for a period of seven days. The permeability of the BBB to proteins was also followed by 125I-albumin transfer from the blood into the brain. A significant edema developed as early as three hours after MCA occlusion. This progressed rapidly to reach a maximum on the third day, gradually regressing thereafter. The increase in the brain water contents showed a parallel time course to the increase in the sodium and decrease in the potassium contents. A significant increase in the BBB permeability to albumin occurred 72 hours after MCA occlusion. However, there was no correlation between the brain water content and BBB permeability to albumin in the hemispheres studied 72 hours after MCA occlusion. The correlation between the brain water and sodium contents was not clear during the first six hours, but became highly significant thereafter. The data suggest that an increase in the BBB permeability to sodium occurred 12-48 hours after MCA occlusion, which, together with an antecedent intracellular shift of sodium, resulted in a massive influx of water and sodium into the brain. The BBB permeability change to sodium, not to proteins, seems to play a predominant role in the pathogenesis underlying ischemic brain edema.
Frequency of echocardiographic abnormalities in patients with ischemia of the carotid territory--a preliminary report.
Authors: Gagliardi R , Benvenuti L , Frosini F , Ammannati F , Barletta G A , Fantini F
Published: June 2011

Eighty-eight consecutive patients referred to a neurosurgical Department (63 men and 25 women) aged from 14 to 68 years, with cerebral ischemia in the carotid territory were subjected to M-mode and two-dimensional echocardiography, carotid angiography and assessment of risk factors. There were 27 patients (average age 54 years) in whom carotid angiography demonstrated a probable source for the ischemia. Carotid angiography was normal in 51 of the remaining 61 (average age 39 years) while 10 revealed distant emboli. Although the incidence of "abnormal echocardiograms" was similar in the two groups (56% and 54% respectively) the spectrum of abnormalities were different. Only 5 (18%) of the 27 patients with abnormal angiograms had a potential cardiac source of emboli while 24 (39%) out of the remaining 61 patients had a potential cardiac source demonstrated at echocardiography. There was a high incidence of mitral valve prolapse (34%) in this latter group of patients. Mitral valve prolapse was not seen in the present series in patients with a probable carotid source on angiography.
Spontaneous dissecting aneurysms of the internal carotid and vertebral arteries--two case reports.
Authors: Mas J L , Goeau C , Bousser M G , Chiras J , Verret J M , Touboul P J
Published: June 2011

Two patients had acute spontaneous dissection of both internal carotid arteries and of one or both vertebral arteries. One had angiographic signs suggestive of fibro-muscular dysplasia and both were on oral contraceptives. They were treated with high dose heparin and made a good clinical recovery. A digital intravenous angiography performed two to three months later showed a complete recanalization of arteries involved. These patients are similar to those reported as "idiopathic regressing arteriopathy" and "reversible angiopathy" which probably correspond to the same entity.
A non-intensive stroke unit reduces functional disability and the need for long-term hospitalization.
Authors: Strand T , Asplund K , Eriksson S , Hägg E , Lithner F , Wester P O
Published: June 2011

In a prospective controlled trial we compared the clinical outcome for unselected acute stroke patients in a non-intensive stroke unit (n = 110) and in general medical wards (n = 183). The patients were comparable in age, marital state and functional impairment on admission. Case fatality rates over the first year after the stroke were similar in the two groups. By three months after the stroke, 15% of the survivors initially admitted to the stroke unit and 39% of those admitted to general medical wards remained hospitalized (p less than 0.001). The corresponding figures by one year after the cerebrovascular accident were 12% and 28%, respectively (p less than 0.05). A greater proportion of surviving stroke unit patients was independent in walking (0.10 greater than p greater than 0.05), personal hygiene (p less than 0.05) and dressing (p less than 0.001). Essential features of the stroke unit are team work headed by a stroke nurse, staff, patient and family education and very early onset of rehabilitation. We conclude that this strategy improves functional outcome and reduces the need for long-term hospital care.
Modification of cerebral ischemia with Fluosol.
Authors: Peerless S J , Nakamura R , Rodriguez-Salazar A , Hunter I G
Published: June 2011

Fluosol-DA (Perfluorochemical Blood Substitute) was investigated in a previous study and found to provide some protection from ischemia and possible usefulness in limiting the size of infarction. In the present study, larger doses over longer periods of acute focal cerebral ischemia were used. Twenty four cats had transorbital ligation of the middle cerebral artery (MCA). The 12 experimental animals were given 20% Fluosol-DA. The control group of 12 received isotonic saline solution. Twenty-four hours after the MCA occlusion, the cats were perfused with saline and phosphate-buffered formalin. The brains were removed and immersed in 10% formalin for 2 weeks. The results of macroscopic and histological examination suggested that, although Fluosol-DA did not provide complete protection from ischemic injury to the brains of the cats treated, it may have helped to slow the development of the pathological changes.
Changes in ambulation and drinking behavior related to stroke in stroke-prone spontaneously hypertensive rats.
Authors: Minami M , Togashi H , Koike Y , Saito H , Nakamura N , Yasuda H
Published: June 2011

In order to elucidate the behavioral changes related to stroke, ambulatory activity and water drinking were observed in stroke-prone spontaneously hypertensive rats (SHRSP). Age matched male SHRSP and Wistar Kyoto rats (WKY) were subjected to a 12 hour light and dark alternation cycle. Ambulation and drinking activity counts were determined simultaneously with an Ambulo-Drinkometer. Before stroke, ambulation and drinking activity counts in the dark phase (82%) were higher than those in the light phase (18%). Both parameters were well synchronized with the light and dark alternation cycle. With aging, daily ambulation decreased while daily drinking activity increased in SHRSP and WKY. Daily ambulation and drinking activity in 15 and 30 week old SHRSP were greater than those of WKY. It was demonstrated with an Ambulo-Drinkometer that SHRSP undergo specific behavioral changes before the onset of stroke. For instance, the 40-60 week old SHRSP showed significant individual variation in both ambulation and drinking activity. This desynchronization with the light and dark alternation cycle was followed by stroke. Twenty seven autopsies showed 11 cerebral infarctions, 10 cerebral hemorrhage and 6 cerebral hemorrhage with infarctions to be the causes of death.
Alterations in alpha adrenergic receptors in human cerebral arteries after subarachnoid hemorrhage.
Authors: Tsukahara T , Taniguchi T , Fujiwara M , Handa H , Nishikawa M
Published: June 2011

The nature of alpha adrenergic receptors in human cerebral arteries was characterized and alteration of these receptors after subarachnoid hemorrhage (SAH) was examined using a radioligand binding assay. The specific 3H-prazosin binding to human cerebral arteries was saturable and of high affinity (KD = 4.1 nM) with a Bmax of 92 fmol/mg protein. Specific 3H-yohimbine binding to these tissues was also saturable and of high affinity (KD = 23 nM) with a Bmax 250 fmol/mg protein. IC50 values of adrenergic agents for 3H-prazosin binding were as follows: prazosin, 1.2 X 10(-10) M; phentolamine, 1.3 x 10(-6) M; yohimbine, 1.2 x 10(-5); norepinephrine, 4.9 x 10(-4) M; epinephrine greater than 1 x 10(-3) M. IC50 values of adrenergic agents for 3H-yohimbine binding were as follows: phentolamine, 1.7 x 10(-7) M; yohimbine, 4.2 x 10(-7) M; prazosin, 1.9 x 10(-5) M; epinephrine, 4.4 x 10(-5) M; norepinephrine, 7.9 x 10(-4) M. KD and Bmax of 3H-prazosin and 3H-yohimbine binding after SAH were compared with findings in the non-SAH group. KD and Bmax of 3H-prazosin binding of SAH group were 6 +/- 3 nM and 90 +/- 10 fmol/mg protein, respectively (N = 3). KD and Bmax of 3H-yohimbine binding of SAH group were 42 +/- 6 nM and 460 +/- 30 fmol/mg protein, respectively (N = 5). On the other hand, KD and Bmax of 3H-prazosin binding in the non-SAH group were 4 +/- 1 nM and 90 +/- 20 fmol/mg protein, respectively (N = 5), KD and Bmax of 3H-yohimbine binding of non-SAH group were 20 +/- 5 nM and 260 +/- 30 fmol/mg protein, respectively (N = 6).(ABSTRACT TRUNCATED AT 250 WORDS)
Non-rheumatic atrial fibrillation as a risk factor for stroke.
Authors: Britton M , Gustafsson C
Published: June 2011

The association between non-rheumatic atrial fibrillation (AF) and stroke has been studied in 402 patients consecutively admitted to a stroke unit. Brain infarction patients with sinus rhythm (n = 196) and non-rheumatic AF (n = 92) were further compared. Some findings supported an embolic origin of the stroke: half of the deceased AF patients (n = 24) at autopsy either had left atrial thrombosis or arterial embolism compared to none of the ten with sinus rhythm. Patients with AF also had a higher mortality and more severe brain lesions, findings compatible with a sudden occlusion of blood flow. However, these differences might also be explained by an atherothrombotic occlusion with impaired autoregulation in the ischaemic region in conjunction with heart failure, which was more common in the AF patients. Other findings supporting an atherothrombotic mechanism were: the prevalence of AF was higher (19-29%) in all kinds of stroke, including haemorrhage, than in age-matched controls (3-9%). Also patients with previous AF and no present embolic source resembled the whole AF group and differed from patients with sinus rhythm. Thus embolism is a plausible cause of stroke in many AF patients, whereas an atherothrombotic origin is more likely in others. Characteristics identifying the mechanism in an individual case were not found.
Fibrinogen, blood viscosity, and cerebral ischemia.
Authors: Grotta J , Ostrow P , Fraifeld E , Hartman D , Gary H
Published: June 2011

This study examines the effect of fibrinogen and consequent blood viscosity reduction on cerebral blood flow and cellular injury following severe cerebral ischemia for 30 minutes in 78 Wistar rats. In half of these rats 10 to 15 cc's of blood was removed and replaced with a mixture of 5% albumin and autologous red blood cells maintaining a constant hematocrit but resulting in a 30% decrease in fibrinogen and corresponding reduction in viscosity. Fibrinogen reduction in a slight increase in baseline CBF and the elimination of post-ischemic hyperemia at 24 hours. Both study and control animals showed a similar decrease in CBF at 30 minutes and 2 hours. There was no significant difference in the severity of ischemic cellular change between the fibrinogen reduction group and controls, although there was a significant inverse relationship between the amount of viscosity change and severity of cellular injury within the treatment group. Fibrinogen reduction alone cannot significantly ameliorate ischemic injury in this model. Viscosity reduction therapy should include reduction of hematocrit and alteration of red cell deformability.
Cerebral ischemic attacks as a complication of aortic and mitral valve prolapse.
Authors: Barletta G A , Gagliardi R , Benvenuti L , Fantini F
Published: June 2011

The high incidence of mitral valve prolapse (MVP) in patients with ischemic attacks is puzzling when compared with the very low incidence of cerebrovascular attacks observed in individuals known to have MVP. Our aim was to determine if it is possible to identify a patient subset with MVP at the highest risk of embolization on the basis of 2D-echocardiographic findings. We compared the echocardiographic picture of a group of 39 patients with MVP and cerebral ischemic attacks (29 TIAs, 10 strokes) in the carotid territory, without any pathological lesions at angiography, with that of a control group of 111 patients with MVP without neurological complications. The two groups were not different for age or sex. Patients with MVP and neurological complications showed a higher prevalence of aortic valve prolapse (62% vs 34%, p less than 0.01), of an association between valvular diffuse thickening and aortic valve prolapse (54% vs 23%, p = 0.001), and of multiple valve prolapse with valvular diffuse thickening (26% vs 7%, p less than 0.01) than those of the control group. This study suggests that in young people cerebral ischemic events could be related to the presence of a combined valve prolapse and to an echocardiographic picture of valve diffuse thickening. These data suggest that in this selected group with multiple valve prolapse and valvar diffuse thickening prophylaxis against embolic events by pharmacological preventive measures should be considered.
Imaging of leukocytic infiltration in human cerebral infarcts.
Authors: Pozzilli C , Lenzi G L , Argentino C , Carolei A , Rasura M , Signore A , Bozzao L , Pozzilli P
Published: June 2011

The circulating white blood cells of patients with brain infarction were labelled in vitro with Indium-111 tropolonate; the cells were reinjected to study the inflammatory process by gamma camera imaging. Eight patients with acute cerebral ischemic infarct were studied during the first two weeks after the onset of neurological symptoms. In seven cases a well defined area of increased radioactivity was revealed in the infarcted hemisphere indicating active migration and tracking of labelled leukocytes in cerebral infarct. This method allows monitoring of the cellular inflammatory response in human cerebral infarcts and adds another imaging technique.
Measurement of activated rCBF by the 133Xe inhalation technique: a comparison of total versus partial curve analysis.
Authors: Leli D A , Katholi C R , Hazelrig J B , Falgout J C , Hannay H J , Wilson E M , Wills E L , Halsey J H
Published: June 2011

An initial assessment of the differential sensitivity of total versus partial curve analysis in estimating task related focal changes in cortical blood flow measured by the 133Xe inhalation technique was accomplished by comparing the patterns during the performance of two sensorimotor tasks by normal subjects. The validity of these patterns was evaluated by comparing them to the activation patterns expected from activation studies with the intra-arterial technique and the patterns expected from neuropsychological research literature. Subjects were 10 young adult nonsmoking healthy male volunteers. They were administered two tasks having identical sensory and cognitive components but different response requirements (oral versus manual). The regional activation patterns produced by the tasks varied with the method of curve analysis. The activation produced by the two tasks was very similar to that predicted from the research literature only for total curve analysis. To the extent that the predictions are correct, these data suggest that the 133Xe inhalation technique is more sensitive to regional flow changes when flow parameters are estimated from the total head curve. The utility of the total head curve analysis will be strengthened if similar sensitivity is demonstrated in future studies assessing normal subjects and patients with neurological and psychiatric disorders.
Prognosis in middle cerebral artery occlusion.
Authors: Moulin D E , Lo R , Chiang J , Barnett H J
Published: June 2011

The natural history of MCA occlusion has become increasingly important since the surgical option of EC/IC bypass surgery has been available. The clinical course of 24 patients with angiographically-demonstrated occlusion of the MCA artery was reviewed. Eight patients presented with a major disabling stroke and five of these died during the acute phase of this ischemic event. The remaining 19 patients were followed for a mean of 54.2 months. There were five deaths in follow-up and two of these were due to subsequent strokes. Fourteen patients manifested a benign course: one of these had a further minor stroke and four had TIAs. Altogether, 3 strokes occurred during the follow-up period (2 fatal, 1 minor) and all were in the territory of the artery known to be occluded. Of those patients who survived their presenting ischemic event, 12 (63%) remained completely functional in terms of activities of daily living. MCA occlusion does not necessarily carry a poor prognosis with medial therapy alone and the role of bypass surgery hopefully will be clarified by the ongoing clinically randomized trial.
A secondary prevention, randomized trial of suloctidil in patients with a recent history of thromboembolic stroke.
Authors: Gent M , Blakely J A , Hachinski V , Roberts R S , Barnett H J , Bayer N H , Carruthers S G , Collins S M , Gawel M G , Giroux-Klimek M
Published: June 2011

Four hundred and thirty-eight patients who had suffered a thromboembolic stroke not less than two weeks or more than four months previously, were entered into a placebo-controlled randomized clinical trial to determine whether suloctidil (200 mg t.i.d.) would influence the subsequent recurrence of stroke, the occurrence of myocardial infarction, or cardiovascular death. The two treatment groups were comparable at baseline with respect to important prognostic variables and there was good adherence to the study protocol during an average follow-up of 20 months. Significantly more patients complained of side-effects in the suloctidil group and more hepatotoxicity was also reported in the suloctidil group. Four cases of clinical hepatitis were suspected to be due to suloctidil, each of which was reversible on termination of study treatment; relative increases in SGOT and SGPT at three months in the suloctidil group were found to be mild and transient. The primary analysis of efficacy was based on the incidence of the first event of stroke, myocardial infarction or cardiovascular death, but excluding events that occurred more than 28 days after complete withdrawal from study medication for whatever reason. Thus, the primary analysis included 38 events in the suloctidil group and 47 in the placebo group (p = 0.17) representing a risk reduction of 24%. If total mortality is substituted for cardiovascular death, the corresponding figures are 47 in the suloctidil group and 58 in the placebo group (p = 0.08).(ABSTRACT TRUNCATED AT 250 WORDS)