bluuebunny/crossref_metadata_2025 huggingface dataset:
Acute Changes in Blood Pressure Following Vascular Diseases in the Brain Stem
Authors: ITO AKIRA , OMAE TERUO , KATSUKI SHIBANOSUKE
Published: June 2011

The relationship of the type of acute change in blood pressure to the site of the brain lesion, following cerebral hemorrhage and infarction, were studied in 108 patients in whom autopsy was performed. No significant changes in blood pressure were observed in cases with lesions localized rostral to the midbrain and in the medulla oblongata. The pressor response characteristic in primary pontine lesions, either hemorrhage or infarction, also was demonstrated in the cerebral hemorrhage with fourth ventricular and pontine extension. Blood pressure elevation was more marked with tegmental pontine lesions than when the lesion was in the basilar pons. Extension of the lesion into neighboring portions of the pons did not cause further change in blood pressure. The present results seem to suggest a positive role of the caudal brain stem, especially the pons, in the blood pressure elevation following the cerebrovascular accidents.
Visual Field Defects and the Prognosis of Stroke Patients
Authors: HAERER ARMIN F.
Published: June 2011

The prognosis of stroke patients is related to the presence or absence of homonymous hemianopia at time of admission to a stroke center. Two hundred thirty-four patients were followed for an average of 15 months. In patients with nonhemorrhagic strokes in the middle cerebral artery territory the presence of a dense homonymous hemianopia lasting for more than 24 hours, together with any degree of motor, sensory or speech defect, seemed to affect adversely the potential for rehabilitation and survival. Data were insufficient to draw similar conclusions with other types of cerebrovascular lesions. The pertinent literature is briefly reviewed.
Increase in Cerebral Blood Flow in the Rabbit by Viquidil
Authors: DE VALOIS J. C.
Published: June 2011

The effect of viquidil, an isomer of quinidine, on the cerebral blood flow of the rabbit was determined using the
85
krypton clearance technique. The experimental animals had a thin polyethylene catheter chronically implanted in one of the internal carotid arteries to facilitate injection of the isotope into the cerebral circulation. At the time of the measurements the animals were artificially ventilated to control arterial P
CO
2
. Viquidil was administered via the implanted catheter at a dose of 5 mg/kg body weight. Cerebral blood flow was measured before injection of the drug (two control measurements of CBF) and ten minutes and 40 minutes after administration of viquidil. This drug causes an increase in cerebral blood flow of about 50 percent, which lasts at least one hour after administration. This increase in CBF was statistically significant (P < 0.02).
Multiple Progressive Intracranial Arterial Occlusions
Authors: MASTRI ANGELINE R. , SILVERSTEIN PAUL M. , GOLD LAWRENCE , ESELIUS ERIK P.
Published: June 2011

A 30-year-old woman experienced a series of strokes over a period of three months. Radiographical studies showed evidence of occlusive disease of the cerebral arteries and a rich collateral circulation typical of multiple progressive intracranial arterial occlusive disease. At autopsy, the involved cerebral arteries showed marked fibrosis of the intima, media and adventitia, degeneration of the internal elastic lamina, and evidence of old and recent thrombosis. These findings are interpreted as a late stage of the disease and give no indication as to its pathogenesis. It is suggested that the vascular disease may have had its onset in childhood with the terminal strokes related to institution of oral contraceptive therapy.
Clinical Grade, Regional Cerebral Blood Flow and Angiographical Spasm in the Monkey After Subarachnoid and Subdural Hemorrhage
Authors: PETRUK KENNETH C. , WEIR BRYCE K. A. , MARRIOTT MICHAEL R. , OVERTON THOMAS R.
Published: June 2011

Subarachnoid and subdural hemorrhage has been induced in the anesthetized monkey by injection of fresh autogenous blood via a needle inserted through a subfrontal twist drill hole. Serial angiographical studies and regional cerebral blood flow (rCBF) determinations were carried out concurrently for three hours following hemorrhage. The changes observed were subsequently correlated with the clinical state of the animals upon reversal of anesthesia.

In general, angiographical vasospasm and a reduction in CBF occurred simultaneously. Occasionally, however, cerebral perfusion remained unaltered after SAH even though marked vasoconstriction of the intradural vessels was present. An excellent correlation between the severity of reduced perfusion and the degree of neurological deficit was found.
Tracheostomies and Stroke
Authors: LANCASTER MARGIE G.
Published: June 2011

Thirteen of 25 stroke patients with tracheostomies died in the hospital. Of the 12 survivors, eight died within two and one-half months after discharge and one lived six months. All nine that died after discharge required continuous nursing home care. One survivor still required total nursing care three and one-half years later and two patients made a good recovery. All three patients living longer than six months following discharge had pontine lesions. There was no difference in the fate of patients with thrombotic or hemorrhagic strokes. Tracheostomies are of questionable value in stroke patients except possibly in those with brain stem lesions.
Stroke in Jerusalem District 1960 Through 1967: An Epidemiological Study
Authors: MELAMED ELDAD , CAHANE ESTHER , CARMON AMIRAM , LAVY SYLVAN
Published: June 2011

An epidemiological study was performed in Jerusalem district on the incidence of new stroke patients during the years 1960 through 1967.

On the assumption that the vast majority of patients with a new cerebrovascular event were either hospitalized in one of the three local hospitals or later referred to the Neurological Outpatient Clinic at the Hadassah University Hospital, a retrospective study was performed in order to obtain a close estimation of the incidence of stroke in the district of Jerusalem. In the period of 1960 through 1967, 1,522 new stroke cases were identified and included in this study. On the basis of the history, clinical picture and auxiliary tests, the patients were divided into three groups: (1) ischemic stroke, (2) stroke due to hemorrhage, and (3) stroke of undetermined type. The criteria for differentiation of cerebral ischemia from hemorrhage were rigid, demanding at least a lumbar puncture, angiography, operation, or autopsy for a diagnosis of either one to be made. These rigid criteria account for the high percentage of undetermined cases. Ischemic stroke was diagnosed in 509 (33%), stroke due to hemorrhage in 181 (12%), and stroke of undetermined type in 832 (55%).

The average annual incidence of stroke in the district of Jerusalem was 90/100,000 population.

The age-specific annual incidence rates showed an almost constant increase for both sexes and the various types of stroke, with increasing age. The age-specific and sexspecific annual incidence rates disclosed a male preponderance for all the age groups above 45 in the "ischemic" and "undetermined" types, and for the total series. This preponderance was marked in the 65 to 74 age group. In the "stroke due to hemorrhage" type there was a slight male preponderance in the 65 to 74 age group and a slight female preponderance in the 75+ age group, the ratio being equal for the total hemorrhagic series. Our findings were compared with those reported in other studies and discussed.
The Hydrogen Clearance Method in Assessment of Blood Flow in Cortex, White Matter and Deep Nuclei of Baboons
Authors: PASZTOR EMIL , SYMON LINDSAY , DORSCH N. W. C. , BRANSTON NEIL M.
Published: June 2011

The technique of hydrogen clearance by an inhalation method is discussed.

The electronic instrumentation necessary to secure stability and reproducibility from the recordings is described.

Clearance rates in gray matter of about 80 ml/100 gm per minute in the cortex and putamen have been obtained, and of about 20 ml/100 gm per minute in white matter.Clearance curves have invariably been monoexponential in character in white matter, and in over half the cases in the putamen. In the remainder of the putamen curves and in 60% of the cortical clearance curves, the curves could be resolved into only two exponentials. Using bicompartmental analysis, the fast-clearing components of biexponential curves in both cortex and deep nuclei gave the same figures as clearance curves of an entirely monoexponential character from these two tissues.

The importance of recirculation time, concentration of hydrogen inhalation, and verification of the tissue placement by subsequent dissection are discussed. The capacity of the method to detect sudden changes in flow during clearance is described.
Cerebral Complications Following Measurements of Regional Cerebral Blood Flow (rCBF) With the lntra-arterial
133
Xenon Injection Method
Authors: INGVAR DAVID H. , LASSEN NIELS A.
Published: June 2011

The rate of complications was studied following measurements of regional cerebral blood flow (rCBF) with the intra-arterial
133
Xenon technique. The investigation was based upon reports of rCBF measurements in close to 4,000 patients, carried out at 18 European and American centers. Two fatalities were reported. The overall rate of complication was found to be 1.3% with permanent neurological sequelae in 0.2%.Almost all complications were reported in patients with arterial or intracranial disease. The complication rates found are equal to, or lower than, corresponding rates following cerebral angiography with carotid puncture. Based upon the experiences reported, some factors are enumerated which appear important in order to keep the rate of complication low.
Intracranial Pressure Gradients Caused by Experimental Cerebral Ischemia and Edema
Authors: O'BRIEN, MICHAEL D. , WALTZ ARTHUR G.
Published: June 2011

To assess the development and resolution of ischemic cerebral edema and brain swelling, measurements of intracranial pressure (ICP) were made in cats after the transorbital occlusion of one middle cerebral artery. Measurement of ICP gradients was difficult: epidural, subdural and intraventricular catheters caused brain damage or failed to function; the accuracy of a miniature strain gauge could not be determined after implantation; and absolute values for intradural pressures could not be obtained with epidural devices. However, variable increases of ICP were recorded on the sides of occlusion from three cats, and were directly related to the severity of the neurological deficits. On the sides opposite occlusion ICP increased slightly or not at all. Several days after occlusion ICP decreased and gradients could not be demonstrated with certainty. Thus, measurements of ICP gradients can be used to assess ischemic cerebral edema and brain swelling, but the usefulness of such measurements is limited at present by methodological problems.
The Effects of Increased Intracranial Pressure on Flow Through Major Cerebral Arteries In Vitro
Authors: FARRAR J. K. , ROACH MARGOT R.
Published: June 2011

The effect of transmural pressure (TMP) (intraluminal minus extraluminal pressure) on flow was measured for 26 isolated major cerebral arteries from human autopsies. The maximum flow rate through an artery was determined by the perfusion pressure (PP), the maximum vessel caliber, and the presence and magnitude of external resistances. Assuming a diastolic PP of 85 mm Hg, intracranial pressure increases above 33±2 SEM mm Hg (45±3 cm H
2
O) resulted in a reduction of flow through these arteries. For atherosclerotic arteries, flow was reduced by 50% at a TMP of 12±1 mm Hg; for nonatherosclerotic arteries, the critical TMP for 50% flow reduction was 20±1 mm Hg. Flow ceased at a TMP of +3 mm Hg for small (cerebellar) arteries to -7 mm Hg for large (posterior cerebral) arteries. For grossly atherosclerotic arteries, this closing pressure was as low as -15 mm Hg. When two arteries were cannulated and perfused in parallel, preferential flow reductions of up to 50% were noted in one of the arteries with no flow change in the other at the same TMP. This preferential narrowing depended on the relative sizes and degree of atherosclerosis of the two arteries.

Wall thickness to lumen diameter ratios were obtained for all arteries and their relevance to the possibility of active closure was discussed.
Epidemiology of In-Hospital Deaths Among Black Stroke Patients
Authors: SHAFER STEPHEN Q. , BRUUN BERTEL , RICHTER RALPH W.
Published: June 2011

Fatality rates in 527 consecutive stroke patients were compared by nine different criteria: age, sex, each of four risk factors or the absence of all, type of lesion, and initial level of consciousness. In the 527, the only significant increases (P < 0.01) in fatality rate were in older patients compared to younger patients (48% versus 34%), hemorrhages compared to infarctions (85% versus 33%), and patients with depressed sensoriums compared to alert ones (65% versus 19%). When the series was split by age (≤ 65 years, ≥ 66 years), younger hypertensives had more fatalities than normotensives (39% versus 24%, P < 0.02), while older hypertensives fared better than normotensives (45% fatalities versus 50%, not significant). For infarction alone, younger hypertensives had 21% fatalities, normotensives 16%; of older hypertensives, 39% died compared to 44% of the normotensives. These differences are not significant (P<0.25).

In this series, it appears that (1) age, initial sensorium, and type of lesion are good discriminant factors in the prognosis for life after stroke, (2) age-specific analysis may highlight other factors operating only in a certain age group, and (3) hypertension may have relatively benign associations among more elderly patients.
Disaggregation of Polyribosomes in Intact Gerbils Following Ischemia. An Ultrastructural Study
Authors: HARTMANN J. FRANCIS , BECKER RUTH A.
Published: June 2011

Adult gerbils were subjected to either unilateral or bilateral common carotid artery ligation for varying periods of time with varying durations of recovery. Selected brain regions were prepared for ultrastructural study after perfusion fixation. Dissociation of polyribosomes was observed in neurons but not in glial cells of the cerebral cortex and thalamus after 30 minutes of unilateral occlusion with no recovery period. At the other extreme, disaggregation was present in all brain regions studied after 60 minutes of bilateral occlusion followed by a 60-minute recovery period. Still longer recovery periods result in the appearance of some neurons with normally aggregated polyribosomes. The results suggest that a relatively long period of ischemia induces a derangement of neuronal protein synthesis that may persist for some time after restoration of circulation.
The Effects of Ventricular Tachycardia on Carotid Artery Blood Flow Velocity
Authors: BENCHIMOL ALBERTO , BALDI JOSE , DESSER KENNETH B.
Published: June 2011

Utilizing the Doppler flowmeter catheter, right carotid blood velocity was measured during episodes of catheter-evoked and pacemaker-induced ventricular tachycardias. Such tachyarrhythmias uniformly diminished peak carotid blood velocity, which in the case of catheter-evoked episodes reduced phasic blood velocity by 50%. At driving rates greater than 140 per minute, the average peak carotid blood velocity was 25% to 50% lower during ventricular when compared with atrial pacing. There was a direct correlation between the ventricular pacing rates and the percent decline of peak carotid blood velocity. Such arrhythmia-related carotid blood velocity deficits may account for syncopal episodes in subjects so affected.
Stroke Surveillance: The Concept of Stroke Team in Diagnosis, Treatment and Prevention
Authors: BORHANI NEMAT O.
Published: June 2011

The Stroke Project in the Sacramento Medical Center has had two primary objectives. These were: (1) to create an atmosphere of stroke awareness by continuous feedback of relevant and reliable information to physicians who care for stroke patients, and (2) to introduce the concept of the stroke team in daily care of the stroke patient in the hospital and beyond.

During a period of two years 171 stroke patients were admitted to the Project. The system devised provided a useful tool in planning objectively the appropriate course of action in patient education and training programs.
Acute and Chronic Effects of Unilateral Cerebral Infarction on the EEG and Behavior of the Rat
Authors: WIEDERHOLT W. C. , PARISER STEVEN F.
Published: June 2011

Anoxic ischemia with resultant unilateral cerebral infarction was produced in the rat by unilateral ligation of the external and common carotid arteries and exposure of the animal to nitrogen. EEG and behavior were studied for one month after the anoxic insult. Infarcted animals showed prominent circling, contralateral flexion postures, and absent visual and tactile placing. At the end of one month the only persistent clinical abnormality was absent contralateral tactile placing. Acutely the EEG showed loss of normal background activity and high voltage slow waves over the infarcted hemisphere. EEG improvement paralleled clinical improvement. At the end of one month only minor asymmetries were observed in the EEG but sleep spindles remained absent on the infarcted side.
Regional Cerebral Blood Flow in Patients With Hypertensive Intracerebral Hemorrhage
Authors: KAWAKAMI HIROSHI , KUTSUZAWA TAKASHI , UEMURA KAZUO , SAKURAI YOSHIHARU , NAKAMURA TAKASHI
Published: June 2011

Regional cerebral blood flow was measured by
183
Xe clearance method in 44 patients with hypertensive intracerebral hemorrhage (HIH) within three weeks from attack. Mean CBF in cases with the more disturbed consciousness was the lower value. There was no definite relationship between mean CBF and the duration from last stroke to measurement. In 44 cases, 35 showed hematoma of so-called "lateral type" and nine showed a "mesial type." There was no difference of mean CBF between these two groups. In the group with lateral-type hematoma, 14 cases were thought to show large space-occupying signs, and their mean CBF was significantly lower than that of the other 21 cases.

In 16 cases, relative hyperemic regions were observed in both the focal and nonfocal areas. In seven cases, relative ischemic regions were frequently in nonfocus rather than focus.

Response of hyperemic region to carbon dioxide was good in seven and poor in three regions in focal area, and was good in eight and poor in one region in nonfocal area. Reactivity of ischemic region to 5% CO
2
inhalation was good in three and poor in zero regions in focus, and was good in three and poor in two regions in nonfocus.

Early venous filling (EVF) was observed in 13 cases and all of them were with lateral-type hematomas.

Only four out of 13 cases showed good correlation between angiographical findings and cerebral circulation.
Effect of Anoxia on Protein Metabolism in Subcellular Fractions of Rabbit Brain
Authors: YANAGIHARA TAKEHIKO
Published: June 2011

The effect of cerebral anoxia on leucine incorporation into proteins of various subcellular fractions from rabbit brain was studied by using a previously reported in vitro model. Although the decrease in leucine incorporation was observed earlier in nuclei and microsomes, other fractions also demonstrated a rapid decrease. These results were quite different from the pattern of leucine incorporation observed in a type of reversible suppression produced with diphenylhydantoin.
Body Weight, Cerebral Atherosclerosis and Cerebral Vascular Disease: An Autopsy Study
Authors: KLASSIN A. C. , LOEWENSON R. B. , RESCH J. A.
Published: June 2011

The severity of atherosclerotic involvement of intracranial cerebral arteries was assessed at autopsy in 3,315 adult subjects. Ponderal index values were calculated for each sex and ten-year age group. In most age groups, subjects with cerebral vascular disease, or one or more of several conditions known to be associated with increased cerebral atherosclerosis, had higher relative body weight than did subjects without those conditions. Subjects in the lower quartile of ponderal index distribution ("overweight" group) had more severe cerebral atherosclerosis than did subjects in the upper quartile ("underweight" group). However, when subjects with disease conditions known to be associated with increased cerebral atherosclerosis were excluded from the analysis, no relationship between relative body weight and severity of cerebral atherosclerosis could be demonstrated. Clinical and/or pathological evidence of cerebral vascular disease was apparently present more often in "overweight" than in "underweight" subjects, at least in certain age groups.
Cerebral Protection During Carotid Endarterectomy
Authors: HOWE JAMES R. , KINDT GLENN W.
Published: June 2011

Carotid endarterectomy was performed on 73 occasions using the following regimen during the operative period: (1) general anesthesia with normothermia, (2) maintaining a normal or slightly elevated arterial oxygen tension (Pa
o
2
, (3) maintaining a normal or low arterial carbon dioxide tension (P
co
2
), (4) maintaining systemic arterial pressure (SAP) at normal or slightly elevated levels, (5) employing a bypass shunt in all cases, and (6) utilizing transient systemic anticoagulation with heparin. The rationale for this regimen is explained in terms of current concepts of cerebral blood flow and metabolism. No new neurological deficit has appeared after operation using these techniques.
Cardiac Abnormalities in Subarachnoid Hemorrhage: A Resumé
Authors: WEINTRAUB BERNARD M. , McHENRY LAWRENCE C.
Published: June 2011

There have been numerous reports demonstrating electrocardiographical changes secondary to subarachnoid hemorrhage, consisting of atrial and ventricular arrhythmias, alterations in QRS configuration, Q-T interval prolongation, T-wave abnormalities, and S-T segment elevation or depression. Abnormalities of cardiac muscle and subendocardial hemorrhage have been seen in patients dying of subarachnoid hemorrhage. Experimental work has shown that electrical impulses in the sympathetic nervous system and hypothalamus produce most of these changes, and the implication is that these changes can be prevented by sympathetic blockade. Pulmonary edema also has been shown to occur frequently after subarachnoid hemorrhage, and again the sympathetic nervous system is implicated in the pathophysiology. Studies done illustrating these points are discussed and conclusions drawn with reference to therapy.
Effects of Catecholamine Infusions on Cerebral Blood Flow and Oxygen Consumption of the Isolated Perfused Dog Brain
Authors: ZIMMER R. , LANG R. , OBERDöRSTER G.
Published: June 2011

Our earlier studies revealed a weak alpha-adrenergic and beta-adrenergic activity of the cerebral vessels of the isolated perfused dog brain. The present investigations were undertaken to determine whether vascular adjustments occur in the cerebral circulation during longer periods of catecholamine infusions. The experiments were performed on six isolated canine brains cross perfused from donor dogs. Norepinephrine (2 µg per minute), epinephrine (2 µg per minute), and isoprenaline (0.2 µg per minute) were applied intra-arterially (i.a.) for a period of ten minutes. Total venous outflow, perfusion pressure in the circle of Willis, and venous O
2
saturation were monitored continuously. Cerebral vascular resistance (CVR) and cerebral O
2
consumption (CMRO
2
) were calculated. Based on the pressure-flow relationship tested in each brain, the indirect effects of catecholamines on CVR caused by autoregulatory influences were calculated and eliminated. During norepinephrine and epinephrine infusions cerebral blood flow (CBF) was found to be decreased by 10.2 ± 6.0% and 4.1 ± 3.3%, respectively, whereas during isoprenaline infusion CBF increased by 9.3 ± 3.6% (mean values ± SD). The maximal changes of CBF were reached in the first or second minute of catecholamine infusion and persisted up to the end of infusion (P > 0.05). After elimination of the indirect effects of catecholamines on CVR, the direct effects on CVR were reduced to about 50% of the original values and remained constant at the level reached during the whole period of infusion. CMRO
2
was not changed (P > 0.05) during infusion of the different catecholamines. Based on these investigations it is assumed that no pronounced vascular adjustments occur in the cerebral circulation during catecholamine infusions.
Glycerol Therapy of Experimental Cerebral Microembolism
Authors: WELCH DENNIS M. , STUDER REBECCA K. , SIEGEL BARRY A.
Published: June 2011

Glycerol was administered to control rats and to animals with experimental cerebral microembolism as a single intravenous injection (1 gm per kilogram), a single one-hour intravenous infusion (1.5 gm per kilogram), daily one-hour intravenous infusions (1 gm per kilogram), or in multiple oral doses (1 gm per kilogram per four hours). There were no effects of glycerol on the mortality, brain edema or increased brain sodium concentration and
75
Seselenate space due to cerebral microembolism. Brain water was not reduced in the hemispheres contralateral to embolization or in glycerol-treated controls. The results suggest that glycerol, at the dose levels reported to be beneficial in human cerebral infarction, is ineffective for cerebral dehydration.
Dynamics and Control Mechanisms in Maintenance of Regional Cerebral Blood Flow
Authors: MOSKALENKO YURI E. , DEMCHENKO IVAN T. , KRIVCHENKO ALEXANDER I. , FEDULOVA INNA P.
Published: June 2011

Experiments with rabbits, cats, and monkeys during recording of complex physiological processes (LEPG, ThG, Po
2
, Pco
2
, and ECoG) in functionally discrete brain regions of awake animals have shown that functional changes, expressed as desynchronization effects on ECoG, are followed by an increase of local blood flow (LCBF) in regional brain cortex up to 0.3 to 0.4 ml per minute per 1 gm brain tissue or an increase of 35% to 45% of resting levels of LCBF. Under normal physiological conditions LCBF and Po
2
change periodically without any external interference at frequency ranges 0.005 to 0.2 cps. This is characteristic of all brain regions and all species of animals investigated. These variations range in amplitude as much as 28% of the mean level of LCBF.

Changes of LCBF have no correlation with changes of systemic blood pressure (SAP). Local control mechanisms appear to be responsible for them. The interrelationships of changes of functional activity and CBF in local regions of awake brain are characterized by a very short time delay (less than one second), but under narcosis it increased up to ten seconds. All these facts taken together suggest that control mechanisms responsible for local brain vascular reactions have two components; the first is metabolic and the second is neurogenic in nature.
The Mechanics of Breathing and Stabilization of Ventilation in Patients With Unilateral Cerebral Infarction
Authors: MCMAHON SAMUEL M. , HEYMAN ALBERT
Published: June 2011

The mechanics of breathing and responses of the respiratory system to CO
2
during resistance breathing were studied in 12 patients with clinical evidence of unilateral cerebral infarction and compared with the findings in normal subjects. The respiratory abnormalities in patients with cerebrovascular disease consisted of noncompliant lungs and high levels of elastic and nonelastic work while rebreathing CO
2
. There were no differences in responses of minute ventilation to CO
2
in the two groups. Unlike normal subjects, the patients did not increase their level of respiratory work to compensate for the addition of a modest external resistance to airflow, and the ventilatory response to CO
2
, consequently, became less than in the normal subjects. This failure to maintain tidal volumes and minute ventilation while breathing through an external resistance may account for some instances of respiratory deterioration among patients with cerebrovascular disease.
Cooperative Study of Intracranial Aneurysms and Subarachnoid Hemorrhage. Report on a Randomized Treatment Study
Authors: NIBBELINK DONALD W. , KNOWLER LLOYD A.
Published: June 2011

Four selected treatments, namely, regulated bed rest, drug-induced hypotension, carotid ligation, and intracranial surgery, were randomly allocated with respect to location of the aneurysm and interval following last bleed. The objective of the Study was to answer the question. "What mode of treatment offers a patient with a single ruptured intracranial aneurysm during the previous three months the highest probability of optimal results with respect to survival. residual neurological deficit, capacity for self-care, and gainful employment? " Various treatments were suspended at specific intervals when a particular mode of therapy became inferior to the others.

A group of 33 patients was disqualified after treatment was randomly allocated. The numbers of protocols remaining for analysis within each treatment category were 202 for regulated bed rest, 309 for drug-induced hypotension, 187 for carotid ligation, and 274 for intracranial surgery.
Cerebrovascular CO
2
Reactivity of the Fast and Slow Clearing Compartments
Authors: ILIFF LINNETTE D. , ZILKHA E. , DU BOULAY G. H. , MARSHALL JOHN , RUSSELL R. W. ROSS , SYMON LINDSAY
Published: June 2011

Regional cerebral blood flow measurements have been made at two levels of Pa
CO
2
, using the clearance of
133
Xenon injected into the internal carotid artery. Specific and percent changes in blood flow per mm Hg change in Pa
CO
2
. (CO
2
reactivity) have been calculated for the fast and slow clearing tissue (Ff and Fs) and F initial. Mean hemisphere CO
2
reactivity was marginally greater in the fast clearing tissue than in the slow clearing tissue (P = 0.05). On a regional basis the greater CO
2
, reactivity of Ff over Fs was significant in five areas (P ≤ 0.05). A strong positive linear correlation between mean specific reactivity and conductance (the reciprocal of resistance) has been demonstrated for Ff and Fs and confirmed in the F initial.
Early Rehabilitative Care in Community Hospitals: Effect on Quality of Survivorship Following a Stroke
Authors: TRUSCOTT B. LIONEL , KRETSCHMANN CLAIRE M. , TOOLE JAMES F. , PAJAK THOMAS F.
Published: June 2011

The effect of early institution of rehabilitative care on quality of survivorship was investigated in 483 patients with their first cerebral infarction. Impaired consciousness at onset adversely affects survivorship and recovery of motor strength. Early institution of rehabilitation was associated with reduced mortality and improved quality of survivorship regardless of severity of the illness, age, or presence of associated diseases.
Amaurosis Fugax: Diagnostic and Therapeutic Aspects
Authors: HOOSHMAND H. , VINES F. S. , LEE H. M. , GRINDAL A.
Published: June 2011

The three to eight-year follow-up study of 34 patients with unilateral amaurosis fugax (AF) suggests the following points: (1) A significant number of frequent unilateral AF patients suffer from small ulcerative plaques or irregular stenoses without any bruit in the neck or major changes in ophthalmodynamometry (ODM). The most important diagnostic test in these cases is angiography. (2) Surgery in patients with frequent unilateral AF seems to be more successful than anticoagulation. (3) No treatment cannot be considered a policy of "benign neglect" and may result in serious complications. (4) Cholesterol plaques, carotid bruits, and abnormal ODM are suggestive of carotid artery disease in unilateral AF. However, the absence of these signs is not helpful in differentiating carotid artery from cardiac origin of the emboli. (5) Heart disease may be the main etiological factor in a few patients with AF. It plays a major role in mortality regardless of the type of treatment.
Tube Feeding and Lethal Aspiration in Neurological Patients: A Review of 720 Autopsy Cases
Authors: OLIVARES LADISLAO , SEGOVIA ALBERTO , REVUELTA ROGELIO
Published: June 2011

A study of 720 autopsy cases from the Instituto Nacional de Neurologia, SSA (INN) and the Centro Hospitalario 20 de Noviembre ISSTE (CH 20 N) was made in order to investigate the frequency of aspiration in postmortem material of neurological cases. Aspiration occurred in 12.5% and 6.5%, respectively, of the cases under study. The clinical features of both groups were quite similar, and slight differences could not account for the uneven proportion of aspiration. When correlating the presence or absence of aspiration in both groups with and without the use of a gastric tube, a significant correlation was found between the use of a tube and the postmortem finding of aspiration. Gastric tube (tube feeding) increases the risk of aspiration six times. Our results support the view that opposes the early, indiscriminate and incautious use of tube feeding in the comatose patient.
Neurovascular Complications of Dialysis and Transplantation
Authors: HARRIS LCDR ROBERT D. , CAMPBELL J. KEITH , HOWARD FRANK M. , WOODS JOHN E. , ANDERSON CARL F. , SAYRE GEORGE P.
Published: June 2011

Dialysis and transplantation are now standard treatments for end-stage renal failure. Often, neurologists are consulted regarding the neurological complications of these therapeutic procedures. In addition to previously reported complications, neurovascular disease is being recognized as a cause of mortality and morbidity in these patients. We report two cases of apparent thromboembolic stroke in young patients with renal failure -- one treated by dialysis and the other by renal transplantation. The risk factors of both dialysis and transplant are identified and data from the American College of Surgeons/National Institutes of Health Transplant Registry are reviewed.
Occlusion of the Carotid Artery: Prognosis (Natural History) and the Possibilities of Surgical Revascularization
Authors: GRILLO PETER , PATTERSON RUSSEL H.
Published: June 2011

A retrospective study was made of a group of 44 patients with arteriosclerotic occlusion of the internal carotid artery trying to identify a group that might benefit from extracranial-intracranial arterial bypass. Eight of the 44 patients died of cerebral infarction. Seven of these deaths were due to the cerebral infarction that prompted the arteriogram and the only fatal infarct during the period of follow-up occurred in the opposite cerebral hemisphere. Four nonfatal strokes occurred during the follow-up period, and these also were in the cerebral hemisphere contralateral to the carotid occlusion. We conclude that the role of extracranial-intracranial arterial bypass is limited to the occasional patient who has recurrent symptoms due to vascular insufficiency in the cerebral hemisphere distal to an occluded carotid or middle cerebral artery. The main role of surgery appears to lie in the opening of the occluded carotid artery in selected patients with acute stroke and in the prophylactic repair of contralateral carotid stenosis.
Polarographical Measurement of Local Cerebral Blood Flow in the Conscious and Anesthetized Primate
Authors: FEIN JACK M. , WILLIS JAMES , HAMILTON JOHN , PARKHURST JOHN
Published: June 2011

This study was undertaken to evaluate the brain hemodynamics of the primate (
Macaca mulatta
) in the conscious and anesthetized state. A polarographical circuit was utilized for repetitive measurements of local and average total cerebral blood flow in the conscious state, during analgesia/paralysis, and in the anesthetized state. The electrochemical considerations and in vitro testing are described. Blood flow values were highest in sensory and motor cortex (92.5 ± 3.5 ml/100 gm per minute and 86.2 ± 2.6 ml/100 gm per minute), while there were no significant differences found between other regions of association cortex. Mean deep gray matter blood flow values ranged between 57.6 ± 3.8 and 69.2 ± 3.4 ml/100 gm per minute. The mean local blood flow for the centrum semiovale was found to be 19.5 ± 1.2 ml/100 gm per minute and that for pontine tegmentum was 58.1 ± 3.5 ml/100 gm per minute. At any one electrode locus, at steady state levels of arterial blood gases, the reproducibility of blood flow ranged between 11% and 18%. Seventy-five percent nitrous oxide/25% oxygen in combination with a paralytic agent produced a questionably significant drop in caudate nucleus blood flow. The depressant effects of anesthetic doses of sodium pentobarbital on cerebral blood flow, however, were significant at most electrode sites. These data indicate that the measured blood flow rates within small brain volumes are critically affected by barbiturate anesthesia and seriously question the value of published reports in which these agents were utilized.
Effects of Bilateral Carotid Artery Ligation on Brain Lactate and Pyruvate Concentrations in Normotensive and Spontaneously Hypertensive Rats
Authors: FUJISHIMA MASATOSHI , SUGI TOMEI , MOROTOMI YASUYUKI , OMAE TERUO
Published: June 2011

Brain lactate, pyruvate, and arterial acid-base balance were measured in normotensive rats (NTR) and spontaneously hypertensive rats (SHR) 60 minutes after bilateral carotid artery ligation. Brain lactate and lactate-pyruvate ratios were significantly increased in both SHR and NTR following carotid occlusion, although lactate increase in the former was six and one-half times greater than in the latter. These findings suggest that bilateral carotid occlusion in SHR may cause more severe circulatory changes which result in increased anaerobic metabolism. Furthermore, higher brain lactate was concomitant with lower arterial carbon dioxide tension. The mechanism of spontaneous hyperventilation following cerebral ischemia was discussed.
Limitations of Radionuclide Flow Studies in Bilateral Carotid Thrombosis
Authors: MESSERT BERNARD , TYSON IAN B. , BARRON STEPHEN A.
Published: June 2011

Radionuclide angiography as a noninvasive procedure has become an important tool in the evaluation of cerebrovascular diseases. Determinations of arm-to-brain circulation times complemented by the transit times of the radionuclide bolus through the brain afford insight into the functional status of the vascular system of the brain. Delays in perfusion, asymmetries in appearance, and washout of the radionuclide material can be correlated with disease entities. However, as with many procedures elevated to the status of a screening test, the possibility of false-positive and false-negative results exists. Two cases of bilateral carotid occlusion are presented, showing normal or only delayed, fairly symmetrical brain perfusion. The appearance of the radionuclide flow in the neck in AP and lateral views gave no suggestion of the involved deficits. Even multiple-projection imaging might fail to demonstrate major vascular obstructions. However, attentive study of these projections might yield interesting evidence of unexpected collateral flow systems.
The Assessment of Insulin, Glucose and Lipids in Ischemic Thrombotic Cerebrovascular Disease
Authors: GERTLER MENARD M. , LEETMA HILLAR E. , KOUTROUBY RUSSELL J. , JOHNSON ELYSE D.
Published: June 2011

Sixty-one male patients with ischemic thrombotic cerebrovascular disease (ITCVD) and 61 age-matched controls were studied to determine the interrelationships between the primary risk factors of ITCVD. Impaired carbohydrate metabolism in ITCVD was reflected in the significantly greater number of abnormal oral glucose tolerance tests (GTT) and type IV lipoprotein abnormalities when compared to controls. Elevated uric acid and triglyceride levels also were observed in ITCVD. Glucose and immunoreactive insulin (IRI) response curves in ITCVD were elevated and exhibited delayed peaks despite the normal or abnormal classification of GTT, indicating that insulin is ineffective in restoring glucose to normal levels. In the ITCVD and control groups with abnormal GTT the free fatty acid (FFA) levels were elevated at fasting and lacked the characteristic rebound at two hours observed in subjects with normal GTT, supporting the theory of a glucose-FFA cycle and its role in carbohydrate disturbances.
Positive Scans in Angiographically Proved Cases of Recanalized Cerebral Infarction
Authors: IRINO TADAYOSHI , TANEDA MAMORU , MINAMI TAKAO
Published: June 2011

In 20 patients with acute major cerebral arterial occlusion, follow-up angiograms were obtained to inspect the occluded artery. These angiograms were compared with brain scans in the fourth week after the stroke. The angiograms revealed that frequent recanalization of the occluded arteries occurred within a week after the onset. On the other hand, brain scans showed the increased uptake of radioisotopes even in the patients with angiographically demonstrated arterial recanalization.

The present study clarified that positive scans could be obtained in the patients with and without recanalization, and emphasized the diagnostic value of brain scans in the subacute or chronic stage of cerebral infarction, especially in patients with no arterial occlusion appearing on the angiograms.
Data Base for Stroke Rehabilitation Using Computerized English Text Discharge Summaries
Authors: STERN PETER H. , LINCOLN JAY C. , ROBINSON MARILYN B.
Published: June 2011

A data processing system
programmed in a terminal-oriented language called APL is described. This user-oriented system features the print-out of
English text discharge summaries
for patients treated in a stroke rehabilitation unit. The variables contained in the summaries are stored in the computer for
statistical analysis
, allowing continuous monitoring of the unit's activities. Seventy-eight percent of patients with moderate to severe hemiparesis were able to return home after an average length of stay of 44 days. The value of the described system is suggested for multicenter, cooperative studies on stroke.
Characterization of Malignant Gliomas and Cerebrovascular Disease by Cerebral Dynamic Studies
Authors: WITHERSPOON LYNN R. , PREISSIG R. S. , MAHALEY M. S. , TYSON J. WENDELL , HARRIS C. CRAIG , LEONARD JOHN R. , GOODRICH JACK K.
Published: June 2011

A technique for analysis of dynamic radionuclide studies of the cerebral circulation is described. This technique permits objective classification of observed radionuclide distribution patterns. Variation in the time-to-peak activity, and in the maximum attained activity as determined by region-of-interest analysis of cerebral hemispheric activity, was defined for a normal population. Application of these normal values permits classification of observed hemispheric radionuclide distribution patterns in anaplastic gliomas and in occlusive cerebrovascular disease. Radionuclide activity in gliomas may be normal, decreased, or increased in the region of the tumor. In cerebrovascular occlusion, decreased activity, associated with a delay in time-to-peak activity, is frequently demonstrated in the affected hemisphere.
The Role of the Peripheral Sympathetic Nervous System in Cerebral Blood Flow Autoregulation
Authors: HERNÁNDEZ-PÉREZ M. J. , RAICHLE M. E. , STONE H. L.
Published: June 2011

The effect of chronic, unilateral superior cervical ganglionectomy on cerebral blood flow and blood flow autoregulation to changes in perfusion pressure was examined in seven phencyclidine anesthetized monkeys. Ten to 14 days prior to the experiments Doppler ultrasonic flow transducers were placed on both carotid arteries after ligation of the external carotid branches and removal of one superior cervical ganglion. Autoregulation was tested by exsanguination and metaraminol infusion with the monkeys inspiring room air, 9% and 12% carbon dioxide in air. Immediately following experimentation the cerebral vessels were examined for the presence of noradrenergic fibers. The results of the study demonstrate that: (1) superior cervical ganglionectomy produces a significant reduction in the noradrenergic innervation of ipsilateral extraparenchymal arteries; (2) the peripheral sympathetic nervous system contributes to overall cerebral vascular resistance primarily by affecting resistance in extraparenchymal arteries; and (3) as a result, it determines the contribution of the extraparenchymal arteries to overall cerebral blood flow autoregulation.
Constriction of Pial Arterioles Produced by Prostaglandin F
2α
Authors: ROSENBLUM WILLIAM I.
Published: June 2011

Prostaglandin F
2α
constricted pial arterioles when locally applied to the cerebral surface. Norepinephrine and serotonin each elicited similar contractile effects. The constriction produced by F
2α
in combination with either biogenic amine was greater than the constriction elicited by F
2α
or amine acting alone. The effect of one agent on the other was additive rather than potentiating. Since F
2α
, norepinephrine and serotonin are all naturally occurring agents, it is possible that their combined effect is important under pathological circumstances and this combined effect should not be overlooked in the search for single spasmogens of great potency. Before ascribing a pathologically important effect to F
2α
, either alone or in combination, evidence is required showing that doses effective in experiments are similar to the concentrations occurring during disease states and/or that vessels may become hypersensitive to F
2α
during such states.
Endothelial Cell Ischemic Injury: Protective Effect of Heparin or Aspirin Assessed by Scanning Electron Microscopy
Authors: GERTZ S. DAVID , RENNELS MARSHALL L. , NELSON ERLAND
Published: June 2011

Scanning electron microscopic observations of the luminal surface of the rabbit common carotid artery subjected to occlusion for 30 minutes or two hours revealed crater-like and balloon-like defects in the endothelial surface. The frequency of occurrence of these abnormalities was significantly decreased by pretreatment with heparin or aspirin in doses considered to have antiplatelet aggregating activity.
Some Experimental Errors in Calculating Regional Cerebral Blood Flow From the Intracarotid
133
Xe Clearance Curve
Authors: KANNO IWAO , UEMURA KAZUO
Published: June 2011

A digital model study has been developed for quantitative assessment of experimental errors in the analysis of
133
Xe clearance curve from the brain. A small Computer synthesized a model of the clearance curve, varying combinations of fast and slow components. The curves were convoluted with Poisson random digits to simulate statistical fluctuations. Identical curves were overlapped with varying intervals to study the influence of remaining activity.

The height over area method to ten minutes was confirmed to overestimate CBF by 10% to 15% with a slow component of 20 ml/100 gm per minute, and the overestimation was increased with a lower slow flow component. The initial slope value was shown to have a close relationship with the fast flow component when the latter was less than 100 ml/100 gm per minute. Errors due to statistical fluctuations were determined only by the initial height (H
0
cps), as the percent standard deviation was ΔH
0
/H
0
in the height over area method and 2ΔH
0
/H
0
logH
0
in the initial slope method, where ΔH
0
= √H
0
. Remaining activity caused errors of 1% to 3% in the initial slope method with an injection interval of 15 minutes. The influence of remaining activity can be eliminated with an injection interval of more than 25 to 30 minutes in the initial slope method and more than 40 minutes in the height over area method.