Showing papers in "Stroke in 1990"

Collagenase-induced intracerebral hemorrhage in rats.

Abstract: Intracranial bleeding is an important cause of brain masses and edema To study the pathophysiology of intracerebral hemorrhage, we produced experimental hemorrhages in 53 rats and characterized the lesion by histology, brain water content, and behavior Adult rats had 2 microliters saline containing 05 unit bacterial collagenase infused into the left caudate nucleus Histologically, erythrocytes were seen around blood vessels at the needle puncture site within the first hour By 4 hours there were hematomas, the size of which depended on the amount of collagenase injected Necrotic masses containing fluid, blood cells, and fibrin were seen at 24 hours Lipid-filled macrophages were observed at 7 days and cysts at 3 weeks Water content was significantly increased 4, 24, and 48 hours after infusion at the needle puncture site and for 24 hours in posterior brain sections Behavioral abnormalities were present for 48 hours, with recovery of function occurring during the first week Brain tissue contains Type IV collagen in the basal lamina Collagenase, which occurs in an inactive form in cells, is released and activated during injury, leading to disruption of the extracellular matrix Collagenase-induced intracerebral hemorrhage is a reproducible animal model for the study of the effects of the hematoma and brain edema

Detection of middle cerebral artery emboli during carotid endarterectomy using transcranial Doppler ultrasonography.

Abstract: The purpose of our study was to define the signal characteristics and clinical circumstances associated with emboli detected in the middle cerebral artery using 2-MHz pulsed transcranial Doppler ultrasound in patients undergoing carotid endarterectomy. Signals designating emboli were transients displaying harmonic qualities the signatures of which were clearly different from those of mechanical and electronic artifacts. We reviewed the audio/video tape recordings from 91 patients for signals of air bubble emboli occurring upon release of common carotid artery crossclamps; recordings from 35 patients (38%) demonstrated air bubble emboli. Transients with signatures identical to those of air bubble emboli were also discovered when bubbles in the bloodstream were improbable; we defined these transients as representing formed-element emboli. Such signals were found in recordings from 24 patients (26%), and they occurred before (both spontaneously and upon common carotid artery compression), during, and after surgical dissection. Signals indicating formed-element emboli were associated with intraluminal platelet thrombus, with ulcerations in the carotid artery, and with transient ischemic attacks or stroke. Most postoperative formed-element emboli did not cause symptoms but, when persisting for hours, they were associated with strokes and cerebral infarction. This Doppler ultrasound method of detecting emboli will be useful in the study of stroke mechanisms and as a clinical test to guide the medical and surgical treatment of patients at risk of stroke.

Cerebral angiographic risk in mild cerebrovascular disease.

Abstract: We review the eight prospective and seven retrospective studies from which it is possible to derive the complication rate of conventional cerebral angiography for patients with mild ischemic cerebrovascular disease who are potential candidates for carotid endarterectomy. Three studies of intravenous and one of intra-arterial digital subtraction angiography are also examined. An overview of the results suggests that the risk of a neurological complication (TIA or stroke) is about 4% and that a permanent neurological deficit (disabling stroke) occurs in about 1%. The mortality rate is very low (less than 0.1%). Systemic complications are not infrequent, particularly with intravenous digital subtraction angiography. The complication rate of cerebral angiography must be considered when evaluating the risks of carotid endarterectomy in patients with ischemic cerebrovascular disease.

Ultrasonic evaluation of early carotid atherosclerosis.

Abstract: We investigated the prevalence of carotid atherosclerosis, including mild early lesions, and its association with cervical bruits and various risk factors (age, male sex, hypertension, hyperlipidemia, diabetes mellitus, obesity, and cigarette smoking) in 232 consecutive Japanese patients. High-resolution real-time B-mode ultrasonography was performed to determine the extent of atherosclerosis, and it was quantified by using a scoring system. The prevalence of carotid atherosclerosis was 49%, 59%, and 41% in all 232 patients, the 100 symptomatic patients, and the 132 asymptomatic patients, respectively. Although carotid lesions were detected frequently (87%) in the 30 patients with cervical bruits, bruits were noted in only 30% of the 88 examined patients with carotid atherosclerosis. Independent risk factors for carotid atherosclerosis in these patients were found to be age, male sex, and hyperlipidemia; diabetes mellitus was a possible risk factor for carotid atherosclerosis. Our study did not show a close association between hypertension and carotid atherosclerosis, and this might be caused by the high prevalence of hypertension in our patients. Our findings suggest an increasing prevalence of carotid atherosclerosis in the Japanese, though this should be confirmed in a population-based study. Our study demonstrates the clinical usefulness of high-resolution B-mode ultrasonography for the evaluation of early carotid atherosclerosis.

Grading the amount of blood on computed tomograms after subarachnoid hemorrhage.

Abstract: According to several studies, the amount of subarachnoid blood on the initial computed tomogram of patients with aneurysmal subarachnoid hemorrhage has predictive value with respect to infarction and outcome. Of several methods for assessing the amount of subarachnoid blood, none has been subjected to a study of interobserver agreement. We describe our own method, applied in previous studies, in which the amounts of blood in 10 basal cisterns and fissures and in four ventricles are graded separately. In grading single computed tomograms of 182 consecutive patients with subarachnoid hemorrhage, the agreement between pairs of three observers, studied with kappa statistics, was relatively good for individual cisterns or fissures (kappa between 0.35 and 0.65) and ventricles (kappa between 0.47 and 0.74). The Spearman rank correlation coefficients for the sum of the scores for subarachnoid and intraventricular blood were very high. Summed scores for extravasated blood are suitable as a baseline variable in follow-up studies of patients with subarachnoid hemorrhage.

Effects of normothermic versus mild hyperthermic forebrain ischemia in rats.

Abstract: We compared the neuropathological consequences of global forebrain ischemia under normothermia versus mild hyperthermia. Twenty-one rats underwent 20 minutes of four-vessel occlusion during which brain temperature was maintained at either 37 degrees C (normothermia, n = 9) or 39 degrees C (hyperthermia, n = 12). Quantitative neuropathological assessment was conducted 1 or 3 days later. At 1 day following the ischemic insult, normothermic rats demonstrated neuronal injury mainly confined to the most dorsolateral striatum. By 3 days, ischemic cells were present throughout the striatum and CA1 hippocampus in normothermic animals. Compared with normothermic rats, intraischemic hyperthermia significantly increased the extent and severity of brain damage at 1 day after the ischemic insult. Areas of severe neuronal necrosis and frank infarction included the cerebral cortex, CA1 hippocampus, striatum, and thalamus. Morphologic damage was also detected in the cerebellum and pars reticulata of the substantia nigra. An overall mortality rate of 83% was demonstrated at 3 days in the hyperthermic ischemic group. We conclude that intraischemic hyperthermia 1) markedly augments ischemic brain damage and mortality compared with normothermia, 2) transforms ischemic cell injury into frank infarction, and 3) accelerates the morphological appearance of ischemic brain injury in regions usually demonstrating delayed neuronal necrosis. These observations on mild hyperthermia may have important implications for patients undergoing cardiac or cerebrovascular surgery as well as patients following cardiac arrest or those with stroke-in-evolution.

Prognosis of transient ischemic attacks in the Oxfordshire Community Stroke Project.

Abstract: In a community-based study of approximately 105,000 people, 184 presented with a transient ischemic attack during the 5 years between 1981 and 1986; we believe these persons represent almost all new cases of transient ischemic attack going to a doctor during that period. During a mean follow-up of 3.7 years 49 patients died, 45 had a first-ever stroke, and 17 had a myocardial infarction. Cardiac disease accounted for 17 (35%) deaths, while stroke was the cause of death in 15 patients (31%). The average actuarial risk of death was approximately 6.3%/yr, slightly greater than that expected for similar people without transient ischemic attacks (risk ratio [observed divided by expected] = 1.4). The actuarial risk of stroke was 11.6% during the first year after a transient ischemic attack and approximately 5.9%/yr over the first 5 years. Patients who suffered a transient ischemic attack had a 13-fold excess risk of stroke during the first year and a sevenfold excess risk over the first 7 years compared with people without transient ischemic attacks. The actuarial risk of death, stroke, or myocardial infarction over the first 5 years after a transient ischemic attack was approximately 8.4%/yr. The prognosis in this community-based cohort was better than that in previous reports. The high early risk of stroke means that investigation and treatment of new cases should commence as soon as possible.

Ultrasonic evaluation of early carotid atherosclerosis.

Abstract: We investigated the prevalence of carotid atherosclerosis, including mild early lesions, and its association with cervical bruits and various risk factors (age, male sex, hypertension, hyperlipidemia, diabetes mellitus, obesity, and cigarette smoking) in 232 consecutive Japanese patients High-resolution real-time B-mode ultrasonography was performed to determine the extent of atherosclerosis, and it was quantified by using a scoring system The prevalence of carotid atherosclerosis was 49%, 59%, and 41% in all 232 patients, the 100 symptomatic patients, and the 132 asymptomatic patients, respectively Although carotid lesions were detected frequently (87%) in the 30 patients with cervical bruits, bruits were noted in only 30% of the 88 examined patients with carotid atherosclerosis Independent risk factors for carotid atherosclerosis in these patients were found to be age, male sex, and hyperlipidemia; diabetes mellitus was a possible risk factor for carotid atherosclerosis Our study did not show a clo

Elevated plasma homocyst(e)ine concentration as a possible independent risk factor for stroke.

Abstract: Homocyst(e)ine refers to the sulfur-containing amino acids homocysteine, homocystine, and homocysteine-cysteine mixed disulfide, which normally exist in plasma in both the free and protein-bound forms. Marked hyperhomocyst(e)inemia is associated with well-recognized complications of occlusive thrombotic events and a characteristic syndrome. It is less clear whether mild to moderate elevations in plasma homocyst(e)ine concentrations (i.e., 1.5-5-fold increases) also represent a risk factor for stroke and, if so, whether it is independent of other recognized risk factors. To examine these questions we compared the plasma homocyst(e)ine levels in 41 patients with acute strokes, 27 patients with transient ischemic attacks, 31 patients with recognized risk factors for but no recent symptoms of cerebrovascular disease, and 31 normal volunteers (controls). Plasma homocyst(e)ine concentration was moderately but significantly higher in the patients than in the controls (p less than 0.0001). Approximately 30% of the patients had homocyst(e)ine levels higher than the controls. No relation was found between homocyst(e)ine concentration and other recognized stroke risk factors or stroke type; however, a positive correlation was found between serum uric acid and plasma homocyst(e)ine levels. These data suggest that a moderately elevated plasma homocyst(e)ine concentration may be an independent risk factor for cerebrovascular disease.

Coagulation factors and the increased risk of stroke in nonvalvular atrial fibrillation.

Abstract: We studied whether hemostatic abnormalities contribute to the increased risk of stroke in patients with nonvalvular atrial fibrillation. Hemostatic function was studied in four age-matched groups: 20 patients with nonvalvular atrial fibrillation and a previous ischemic stroke, 20 patients with nonvalvular atrial fibrillation without a previous stroke, 20 stroke patients with sinus rhythm, and 40 healthy controls. Both groups with nonvalvular atrial fibrillation had significantly higher concentrations of von Willebrand factor, factor VIII:C, fibrinogen, D-dimer (a fibrinolytic product), beta-thromboglobulin, and platelet factor 4; a significantly higher fibrinogen/antithrombin ratio; and significantly higher spontaneous amidolytic activity than the healthy controls. Prekallikrein levels were significantly lower in both groups with nonvalvular atrial fibrillation. Stroke patients with sinus rhythm had normal hemostatic function, normal concentrations of platelet-related factors, and a slightly increased concentration of fibrinopeptide A compared with the healthy controls. Both groups with nonvalvular atrial fibrillation differed from the stroke patients with sinus rhythm as they did from the healthy controls. No difference in hemostatic function was seen between the nonvalvular atrial fibrillation patients with and without a previous ischemic stroke. Thus, alterations in hemostatic function may contribute to the increased risk of stroke in patients with nonvalvular atrial fibrillation.

Predictors of stroke outcome using objective measurement scales.

Abstract: We set out to determine if rehabilitation variables predicted the motor and functional outcomes of stroke patients. Using the Modified Motor Assessment Scale (motor status) and the Barthel Index (functional status), we tested 50 stroke patients less than or equal to 3 days, 1 week, and 1 month after their stroke and at discharge from the hospital. Both measures are reliable and valid. We used the Spearman correlation coefficient (r) and stepwise regression analysis to analyze the data. Balanced sitting and bladder control scores at 1 week correlated significantly with motor score at discharge (r = 0.83), Barthel Index score at discharge (r = 0.82), and walking score at discharge (r = 0.80). The combined arm score at 1 month correlated significantly with the combined arm score at discharge (r = 0.94). Regression equations using the scores at 1 month produced the highest r2 values (range 0.76-0.95) in predicting the Barthel Index, motor, walking, and arm recovery scores at discharge. The correlation coefficients and the regression equations have uses in both research and clinical settings. We suggest that these objective predictors of recovery be used as adjuncts in prioritizing and directing the rehabilitation management of patients with stroke.

Arm and leg paresis as outcome predictors in stroke rehabilitation.

Abstract: I used leg and arm paresis to predict outcome measured as extremity function in a prospective study of 75 consecutive hemiplegic patients admitted to an inpatient stroke rehabilitation unit. In each patient, extremity paresis was quantified according to the five-point scoring system advised by the Medical Research Council, upper extremity function was quantified using the Barthel Index subscore for feeding and dressing the upper body, and lower extremity function was quantified according to a five-point scoring of the ability to walk. Improvement was recorded for upper extremity function in 52% of the patients and for lower extremity function in 89%. Best extremity function was reached a mean +/- SEM of 9 +/- 3 and 10 +/- 4 weeks after stroke for the upper and lower extremities, respectively. In patients experiencing complete recovery, this occurred a mean +/- SEM of 7 +/- 2 weeks (for both upper and lower extremities) after the stroke. Only 8-11% of the patients with paresis scores of less than or equal to 2 regained independent extremity function after rehabilitation. Half of the patients with paresis scores of greater than or equal to 3 regained independent extremity function after rehabilitation, while the other half were able to perform extremity function with only minimal assistance. As predictors of extremity function, the Barthel Index subscore was slightly better (r = 0.64) than paresis score (r = 0.58). However, because evaluation of extremity paresis is easy, it appears to be useful as a preliminary predictor of outcome following stroke.

Stroke in young adults.

Abstract: Strokes in young adults are uncommon and often a diagnostic challenge. A retrospective study of strokes due to intracerebral hemorrhage, subarachnoid hemorrhage, or cerebral infarction was undertaken. We reviewed the medical records of 113 young patients aged 15-45 years who were admitted to the Medical Center Hospital of Vermont with a diagnosis of stroke between 1982 and 1987. This group comprised 8.5% of patients of all ages admitted for stroke, 2.3 times the proportion observed in the National Survey of Stroke. Nontraumatic intracerebral hemorrhage was diagnosed in 46 young patients (41%); the main causes included aneurysms, arteriovenous malformations, hypertension, and tumors. Subarachnoid hemorrhage was found in 19 young patients (17%); the majority were due to aneurysms. The remaining 48 young patients (42%) had cerebral infarction, the majority due to cardiogenic emboli and premature atherosclerosis. Mitral valve prolapse, the use of oral contraceptives, alcohol drinking, and migraine were infrequent sole causes of cerebral infarction in the absence of other risk factors. The case-fatality rate for this group of young patients with stroke was 20.4% compared with 23.9% for the National Survey of Stroke. Young adults with stroke deserve an extensive but tailored evaluation, which should include angiography and echocardiography.

Transcranial color-coded real-time sonography in adults.

Abstract: We investigated the diagnostic potential of transcranial color-coded real-time sonography in 52 individuals using a phased-array ultrasound system with color-coded blood flow representation. Ultrasound scans in the axial and coronal planes were feasible through temporal acoustic bone windows in 49 subjects, enabling depiction of the main parenchymal and vascular structures as well as the ventricular system. Color-coded representation of blood flow in the cerebral vessels allowed unequivocal identification of the circle of Willis within the anatomic black-and-white B-mode image of the parenchymal structures. In Doppler mode, vascular blood flow phenomena may be analyzed semiquantitatively using the Doppler frequency spectrum. This noninvasive, serially applicable, mobile beside method may complement conventional neuroradiologic imaging methods, allowing on-line studies of functional processes within the adult brain.

Correlation between amino acid release and neuropathologic outcome in rat brain following middle cerebral artery occlusion.

Abstract: Using in vivo brain microdialysis, we studied amino acid release in the striatum and cortex of eight rats following permanent middle cerebral artery occlusion. We then processed all brains for histopathologic assessment of the volume of ischemic damage 4 hours after occlusion. Ischemic damage was varied by occlusion of the middle cerebral artery at a point either proximal (n = 4) or distal (n = 4) to the lenticulostriate vessels. Proximal occlusion elevated the dialysate contents of all amino acids. The largest increases occurred for the potentially neurotoxic amino acids aspartate and glutamate and for taurine (800-2,800% of basal efflux). We observed smaller increases for the "metabolic" amino acids (280-580% of basal efflux). Distal occlusion did not affect amino acid efflux in the striatum, and release in the cortex was significantly lower than that following proximal occlusion. We compared release data with acute histopathologic outcome. Proximal occlusion resulted in a large volume of ischemic damage in the cortex and striatum (25-48% of hemispheric volume). A smaller volume of ischemic damage was noted following distal occlusion (0-21% of hemispheric volume). The volume of ischemic damage and the amount of amino acid release were significantly correlated (p less than 0.05).

International trends in stroke mortality: 1970-1985.

Abstract: We compared the pattern of cerebrovascular disease (stroke) mortality in men and women aged 40-69 years in 27 countries during 1970-1985 with the decline in coronary heart disease mortality during the same period. Stroke mortality rates declined in 21 and 25 countries for men and women, respectively. In 23 countries the decline in stroke mortality in women was greater than that in men. Countries with the highest rates of stroke mortality are also those with the least favorable secular trend. The rate of decline for stroke mortality is greater than that for coronary heart disease mortality in those countries that experienced a decline in both categories. International comparisons of risk factor levels over time are required to explain the striking differences between countries.

Dementia in stroke survivors in the Stroke Data Bank cohort. Prevalence, incidence, risk factors, and computed tomographic findings.

Abstract: We determined the prevalence of dementia in 927 patients with acute ischemic stroke aged greater than or equal to 60 years in the Stroke Data Bank cohort based on the examining neurologist's best judgment. Diagnostic agreement among examiners was 68% (kappa = 0.34). Of 726 testable patients, 116 (16%) were demented. Prevalence of dementia was related to age but not to sex, race, handedness, educational level, or employment status before the stroke. Previous stroke and previous myocardial infarction were related to prevalence of dementia although hypertension, diabetes mellitus, atrial fibrillation, and previous use of antithrombotic drugs were not. Prevalence of dementia was most frequent in patients with infarcts due to large-artery atherosclerosis and in those with infarcts of unknown cause. Computed tomographic findings related to prevalence of dementia included infarct number, infarct site, and cortical atrophy. Among 610 patients who were not demented at stroke onset, we used methods of survival analysis to determine the incidence of dementia occurring during the 2-year follow-up. Incidence of dementia was related to age but not sex. Based on logistic regression analysis, the probability of new-onset dementia at 1 year was 5.4% for a patient aged 60 years and 10.4% for a patient aged 90 years. With a multivariate proportional hazards model, the most important predictors of incidence of dementia were a previous stroke and the presence of cortical atrophy at stroke onset.

Liposome-entrapped superoxide dismutase reduces cerebral infarction in cerebral ischemia in rats.

Abstract: We studied the role of superoxide radicals in the pathogenesis of ischemic brain injury using a model of focal cerebral ischemia in 102 rats and liposome-entrapped CuZn-superoxide dismutase, which can penetrate the blood-brain barrier and cell membranes efficiently The bolus intravenous administration of 25,000 units of liposome-entrapped CuZn-superoxide dismutase elevated superoxide dismutase activities in the blood and brain 1, 2, 8, and 24 hours later as well as in the ischemic hemisphere and contralateral cortex Determined 24 hours after right middle cerebral and bilateral common carotid artery occlusion by the lack of staining for mitochondrial dehydrogenase activity with 2,3,5-triphenyltetrazolium chloride, infarct sizes were reduced by 33%, 25%, and 18% in the anterior, middle, and posterior brain slices, respectively, by treatment with liposome-entrapped CuZn-superoxide dismutase Our data demonstrate that superoxide radicals are important determinants of infarct size following focal cerebral ischemia and that liposome-entrapped CuZn-superoxide dismutase may have pharmacologic value for the treatment of focal cerebral ischemic injury

Risk factors for stroke in middle-aged men in Göteborg, Sweden.

Abstract: To evaluate stroke risk factors in Goteborg, Sweden, during 1970-1973 a cohort of 7,495 participating men from a general population sample of 9,998 men aged 47-55 years were examined with respect to cardiovascular risk factors. Men with hypertension and hypercholesterolemia and men who were heavy smokers were treated. We assessed stroke end points and cause-specific mortality using a stroke register and death certificates. During a mean follow-up of 11.8 years, 230 strokes occurred in the entire population sample (participants and nonparticipants) (7% subarachnoid hemorrhages, 13% intracerebral hemorrhages, 42% cerebral infarctions, and 38% unspecified strokes). Using univariate analysis, we found measured high blood pressure (systolic and diastolic), smoking, known hypertension, diabetes mellitus, stroke in either parent, severe psychological stress, marital status, atrial fibrillation, previous transient ischemic attacks, previous myocardial infarction, effort-induced chest pain, and intermittent claudication to be significantly related to all stroke. Of the stroke types, subarachnoid hemorrhage was not related to any of these indicators, and intracerebral hemorrhage was related only to measured high blood pressure. Using multivariate analyses, we found measured high blood pressure, smoking, and severe psychological stress as well as atrial fibrillation, previous transient ischemic attacks, and intermittent claudication to be independent risk factors for nonhemorrhagic stroke. Serum cholesterol concentration, occupational and leisure-time physical activity, body mass index, alcohol abuse, and low occupational class were not risk factors for stroke.

Free radicals in central nervous system ischemia.

Abstract: Free radicals have been implicated in a wide variety of diseases and in the toxic and therapeutic effects of antineoplastic drugs and radiation, the deleterious consequences of environmental pollutants, and \"degenerative\" processes such as aging and Parkinson's disease.Their involvement in myocardial and intestinal as well as central nervous system (CNS) ischemia is under intensive study. A free radical is any molecule, atom, or group of atoms with an unpaired electron in its outermost orbital. Since covalent chemical bonds usually consist of a pair of electrons sharing an orbital, free radicals can be thought of as molecules with an \"open\" or \"half bond, which accounts for their extreme reactivity. Free radical species of potential importance in cerebral ischemia include superoxide (O2~-) and hydroxyl (OH-). [By convention, the single unpaired electron in a free radical is represented by a dot.] In the acidic conditions of ischemic brain, O2~is probably protonated (HO2~-). The OHradical is the more reactive and more toxic of these two molecules. Hydrogen peroxide (H2O2), while not a free radical per se, has the potential to generate OHradicals in reactions with O2~-, catalyzed by iron (or other transition metals): O2~+H2O2-»O2+OH~+OH-. In order to function as a catalyst for this reaction, the Fe must not be bound to proteins. Since unlike most extracellular fluids the cerebrospinal fluid (CSF) has low concentrations of Fe-binding proteins, iron released from damaged brain cells is more likely to be readily available to catalyze the generation of OH-. Fe can also donate electrons to H2O2 to form OH-: H2O2+Fe ^Fe+OH-+0H\". Because H2O2 is nonpolar, it readily crosses membranes unlike O2~\\ Free radicals are produced in small amounts by normal cellular processes. The mitochondrial electron transport system is designed to add four electrons to O2, reducing it to H2O and avoiding the reactive species produced by single electron reduction of O2. However, \"leaks\" in mitochondrial electron transport allow O2 to accept single electrons, forming O2~\\ Free radicals are produced in the reactions catalyzed by prostaglandin hydroperoxi-

Stroke in infective endocarditis.

Abstract: We reviewed 212 consecutive episodes of infective endocarditis in 203 patients at six hospitals between 1978 and 1986 and found that 21% were complicated by stroke. Of 133 episodes involving native mitral and/or aortic valves, brain ischemia occurred in 19%, brain hemorrhage in 7%, and non-central nervous system emboli in 11%; vegetations were identified in 56% of 113 adequate echocardiograms and did not correlate with risk of embolism. In native-valve endocarditis, most (74%) ischemic strokes had occurred by the time of presentation and an additional 13% occurred less than or equal to 48 hours after diagnosis; the incidence of brain ischemia was 13% on presentation, 3% during the first 48 hours of hospitalization, and 2%-5% during the remainder of the acute course. Stroke recurred at a rate of 0.5%/day, often heralding relapse/uncontrolled infection. Only 9% of ischemic infarcts were large (all in patients with Staphylococcus aureus infection), while 8% were small and subcortical. Brain hemorrhage occurred primarily at the time of presentation, particularly in intravenous drug abusers, and was associated with uncontrolled S. aureus infection with pyogenic arteritis. Ischemic and hemorrhagic stroke continue to be frequent and important in patients with infective endocarditis and are clustered during uncontrolled infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Treatment of right hemispheric cerebral infarction by hemicraniectomy.

Abstract: An anecdotal series of nine patients (three men and six women with an average age of 57 years) presented with progressive neurologic deterioration while on medical therapy for large right hemispheric cerebral infarction. Clinical signs of uncal herniation (anisocoria or fixed and dilated pupils, and/or left hemiplegia with right decerebrate posturing) were present in seven of these nine patients. Computerized tomography of the head confirmed mass effect from cerebral edema. It was the clinical judgment of the treating neurologists and neurosurgeons that each of these nine patients would perish unless surgical decompression of the infarcted brain was performed. Accordingly, each was treated with right hemicraniectomy and dural augmentation. Six patients demonstrated neurologic improvement on the first postoperative day. One patient, with a postoperative diagnosis of lung cancer, died 1 month after surgery. The remaining eight patients are currently living with their families with a follow-up period ranging from 5 to 25 months. Patient outcome as evaluated by the Barthel Index indicates that three individuals are functioning with minimal assistance and that the remaining six patients are functionally dependent. After rehabilitative therapy, four patients returned for elective cranioplasty. These results suggest that hemicraniectomy can be an effective lifesaving procedure for malignant cerebral edema after large hemispheric infarction.

Incidence of hypertension and stroke in relation to body fat distribution and other risk factors in older women.

Abstract: The relation between body fat distribution, as measured by the waist-to-hip circumference ratio, and the 2-year incidences of hypertension and stroke were examined in a cohort of 41,837 women aged 55-69 years. Women who developed hypertension were 2.1 (95% confidence interval 1.7-2.6) times more likely to be in the upper tertile of waist-to-hip ratio than those who did not. Adjustment for age, body mass index (kilograms per meter squared), cigarette smoking, physical activity, alcohol intake, and education level reduced this odds ratio to 1.6 (95% confidence interval 1.3-2.1). Women who developed a stroke were also 2.1 (95% confidence interval 1.5-2.9) times more likely to be in the upper tertile of waist-to-hip ratio than those who did not. Adjustment for the same covariates also lowered this odds ratio to 1.6 (95% confidence interval 1.1-2.4). Further adjustment for hypertension and diabetes mellitus reduced the estimated risk of stroke due to elevated waist-to-hip ratio to 1.3 (95% confidence interval 0.8-2.1). Hypertension, diabetes mellitus, and cigarette smoking remained significantly associated with stroke incidence in the multivariate model. These results indicate that abdominal adiposity, as measured by an increased waist-to-hip ratio, increases the risks of hypertension and stroke, even after accounting for overall body mass. The association of abdominal adiposity with risk of stroke is related, in part, to the association of abdominal adiposity with hypertension and diabetes.

Efficiency, effectiveness, and duration of stroke rehabilitation.

Abstract: This prospective multicenter study identifies the variables significant in the prediction of rehabilitation efficiency, achievement of rehabilitation potential and duration of rehabilitation stay in 258 persons with a first stroke admitted to comprehensive inpatient rehabilitation in Brisbane, Australia, during 1984. All three dependent variables were poorly predicted, with only 17% of the variance in rehabilitation efficiency, only 30% of the variance in achievement of rehabilitation potential, and only 22% of the variance in duration of rehabilitation stay explained. Unlike other reports, we considered most of the major medical (side of paralysis, stroke etiology, site of the lesion, arterial distribution affected, etc.), rehabilitative (initial Barthel Index score, interval from stroke onset to acute-care hospital admission, interval from hospital admission to rehabilitation commencement, neurologic measures, etc.), and demographic (age, years of education, occupation, ethnicity, etc.) variables. The high proportion of unexplained variance is likely to be due to nonmedical factors influencing the selection of patients for rehabilitation.

Clinical features of proven basilar artery occlusion.

Abstract: Our study describes the early symptoms and signs of 85 patients with either basilar artery occlusion or bilateral distal vertebral artery occlusion documented by selective angiography. The most common prodromal symptoms were vertigo, nausea, and headache, which occurred during the 2 weeks before the stroke. Angiographic findings of 49 patients were classified into proximal, middle, and distal basilar artery occlusions. Twenty-two of these patients had additional vertebral artery lesions. A fourth group was composed of 36 patients with bilateral distal vertebral artery occlusion without opacification of the basilar artery through a vertebral artery injection. Onset was sudden in 20 patients; sudden, but preceded by prodromal symptoms in 11 patients; and progressive in 54 patients. Patients with progressive strokes often had bilateral vertebral artery occlusions. Most patients with acute onset had occlusion of the middle and distal basilar artery. An embolic origin of basilar artery occlusion from an arteriosclerotic vertebral artery lesion was assumed to be an important mechanism. An embolus reaching the basilar artery may not necessarily reach the top of the artery, but may also become lodged more proximally.

Seasonal variation in stroke incidence in Hisayama, Japan.

Abstract: We investigated seasonal variation in the incidence of cerebral stroke among the general population aged greater than or equal to 40 years in November of 1961 in Hisayama, Japan. During the 24-year follow-up period, 311 cases of cerebrovascular diseases occurred. The date or month of onset was determined in 308 cases, of which 51 were classified as intracerebral hemorrhage, 223 as cerebral infarction, and 27 as subarachnoid hemorrhage. We observed a significant seasonality in the incidence of all stroke (p less than 0.01), of intracerebral hemorrhage (p less than 0.05), and of cerebral infarction (p less than 0.01), whereas subarachnoid hemorrhage had no significant seasonal pattern. Subjects less than 64 years of age showed a significant seasonal variation in the incidence of both intracerebral hemorrhage (p less than 0.05) and cerebral infarction (p less than 0.01). A significant seasonal pattern for the incidence of intracerebral hemorrhage was also noted among persons with hypertension (p less than 0.05) or a high serum cholesterol level (p less than 0.05), whereas such a pattern for cerebral infarction was documented among normotensive persons (p less than 0.05) and those with a low serum cholesterol level (p less than 0.01). In addition, the incidences of intracerebral hemorrhage and cerebral infarction were negatively correlated with mean ambient temperature (p less than 0.01 and p less than 0.05, respectively), and all stroke and intracerebral hemorrhage in men were significantly related to intradiurnal temperature change (p less than 0.05 and p less than 0.01, respectively). The significance of the seasonal occurrence of stroke is discussed in relation to relevant risk factors.

Hematologic disorders and ischemic stroke. A selective review.

Abstract: More than a dozen primary hematologic disorders have been associated with ischemic stroke. Inherited deficiencies of antithrombin III, protein C, and protein S have been linked with stroke in case reports; optimal screening requires functional as well as antigenic assays. Antiphospholipid antibodies and lupus anticoagulants are the most frequently identified acquired states associated with ischemic stroke. Polycythemia vera, sickle cell anemia, sickle-C disease, and essential thrombocythemia are the major disorders of formed blood elements causing stroke. Special, step-wise screening for occult prothrombotic entities in stroke patients is recommended for young persons with stroke of uncertain cause, for those with prior venous thrombosis, for those with a family history of unusual thrombosis, and for those with no other explanation for recurrent stroke. Acquired, perhaps transient, abnormalities of platelets, coagulation inhibition, and fibrinolysis may contribute importantly to brain ischemia in synergy with other mechanisms, but at present these remain ill-defined. The contribution of prothrombotic diatheses to stroke is probably underrecognized and warrants further investigation.

Are hypertension or cardiac embolism likely causes of lacunar infarction

Abstract: We tested the hypothesis that hypertension is more common and cardiac embolism less common in patients with lacunar infarction than in patients with other types of cerebral infarction. We studied risk factor profiles in a series of 102 consecutive patients with a lacunar infarct and 202 consecutive patients with a carotid artery-distribution infarct involving the cortex registered in the Oxfordshire Community Stroke Project, a community-based study of first-ever stroke. The two groups did not differ in the prevalence of prestroke hypertension (defined in a number of ways) or in the prevalence of markers of sustained hypertension. The presence of atrial fibrillation and a history of myocardial infarction, particularly during the 6 weeks before the stroke, were significantly more common in the group with carotid-distribution infarcts involving the cortex. There was no significant difference in the prevalence of other accepted risk factors for ischemic stroke, including previous transient ischemic attack, cervical bruit, diabetes mellitus, peripheral vascular disease, or cigarette smoking. Our results suggest that hypertension is no more important in the development of lacunar infarction than it is in the development of other types of ischemic stroke that are presumed to be due to atherosclerotic thromboembolism in a major cerebral artery. Our data support the autopsy evidence that cardioembolic occlusion is an unusual cause of lacunar infarction.

Intracerebral hematomas during anticoagulant treatment.

Abstract: We retrospectively studied 79 patients from three centers who suffered an intracerebral hemorrhage during treatment with anticoagulants and compared them with 84 patients from one center who suffered a spontaneous intracerebral hemorrhage without anticoagulant treatment. Mortality after 30 days was slightly higher in patients with anticoagulant treatment (67%) than in those without (55%), and the proportion of patients who attained moderate or complete recovery was slightly smaller in the treated group (22% and 36%, respectively); neither difference was statistically significant. Volume of the supratentorial hematoma was measured from computed tomograms in 70% of the patients in both groups and was significantly greater in the 55 patients treated with anticoagulants than in the 59 patients not so treated. Volume was not related to the degree of anticoagulation. Based on the total number of patients treated with anticoagulants in the Heerlen region, we conclude that for patients older than 50 years of age the risk of intracerebral hemorrhage during anticoagulant treatment is increased approximately eightfold but is unrelated to the degree of anticoagulation. Our results suggest that intracerebral hemorrhage is more frequent and more extensive in patients treated with anticoagulants but that once it has occurred in such patients intracerebral hemorrhage is not significantly more serious than in untreated patients.