bluuebunny/crossref_metadata_2025 huggingface dataset:
Increased Binding of Norepinephrine by Nerves to Cerebral Blood Vessels: Evidence from the Effects of Reserpine on Nerves to Cerebral and Extracerebral Blood Vessels
Authors: ROSENBLUM WILLIAM I.
Published: June 2011

It has been proposed by others that adrenergic nerves to cerebral blood vessels bind norepinephrine more avidly than do nerves to vessels outside the brain. This suggestion is supported by the present data which show that in the rat intraperitoneal reserpine depletes norepinephrine less readily from nerves to cerebral blood vessels than from nerves to extracerebral blood vessels. Alternate hypotheses to explain our data are contradicted by available evidence, except for the hypothesis of unequal distribution of reserpine between perivascular nerves in various locations. No evidence has been located to favor the latter hypothesis. The postulate of increased norepinephrine binding by nerves to cerebral vessels not only explains the present data, but also can account for the surprisingly small responses of cerebral vessels to exogenous norepinephrine or to sympathetic stimulation.
Arterial Peaks in Regional Cerebral Blood Flow
133
Xenon Clearance Curves
Authors: ROSENBAUM STEPHEN G. , ILIFF LINNETTE D. , BULL J. W. D. , DU BOULAY G. H. , MARSHALL JOHN , RUSSELL R. W. ROSS , SYMON LINDSAY
Published: June 2011

In patients with normal rCBF, arterial spikes are found in all regions of the cerebral hemisphere. The normal range of spike height is 17% to 31 % of H max, except over the carotid siphon (region 15), when it is 36% to 38%.

Under general anesthesia proportionate spike height increases significantly when CBF is low. Increased blood flow is not, however, significantly associated with decrease in spike height.

The possible explanations for this are discussed.
Effect of pH on Metabolism and Ultrastructure of Guinea Pig Cerebral Cortex Slices
Authors: PATEL KUSUM K. , HARTMANN J. FRANCIS , COHEN MAYNARD M.
Published: June 2011

Lactic acidosis is a prominent biochemical alteration which follows cerebral ischemia and is of sufficient degree to result in pH decrease in involved and adjacent tissue. Because of the significance of acidosis in the cerebral ischemic process, we have investigated ultrastruclural changes and some biochemical parameters under varying pH conditions using guinea pig cerebral cortex slices.

Metabolic rates decreased markedly during acidic incubations, and increased only minimally during basic incubations. Acidic pH affected oxygen and glucose utilization rates and fine structure to a greater degree than did an equal change in pH from 7.4 toward the alkaline. Glucose consumption was affected by pH deviations from 7.4 to a greater degree than oxygen uptake.
Cholinergic Control of Blood Flow in the Cerebral Cortex of the Rat
Authors: SCREMIN OSCAR U. , ROVERE ALFREDO A. , RAYNALD AUGUSTO C. , GIARDINI ADOLFO
Published: June 2011

Local blood flow was measured in the somatosensory cortex of urethanized rats by means of the hydrogen clearance method. The variations of cortical blood flow in the course of the anesthesia and the effects of the topical application of atropine, eserine and cholinomimetic drugs were studied. During urethan anesthesia, the electrical activity of the cerebral cortex fluctuated between a synchronized and a desynchronized state. During desynchronization, local cortical blood flow increased significantly. This increase in blood flow could be prevented by topical application of atropine and exaggerated by topical eserine. Topical application of arecoline, carbaminoylcholine, pilocarpine or acetylcholine with eserine significantly increased cortical blood flow. It is concluded that the increase in cortical blood flow that accompanies cortical desynchronization in the urethanized rat is mediated, at least in part, by a neurogenic mechanism that involves a cholinergic step at the cortical level.
The Effects of Arterial Blood Pressure on the Regional Cerebral Blood Volume by X-Ray Fluorescence
Authors: GRUBB ROBERT L. , PHELPS MICHAEL E. , RAICHLE MARCUS E. , TER-POGOSSIAN MICHEL M.
Published: June 2011

Cerebral blood flow (CBF) remains constant over a wide range of arterial blood pressure. This is thought to be accomplished by changes in the diameter, and therefore the volume, of the cerebral resistance vessels. To test this hypothesis, regional cerebral blood volume (rCBV) was measured in vivo in Rhesus monkeys over a range of mean arterial blood pressures (MABP) of 35 to 200 torr. Multiple measurements were made in each animal by the method of stimulated x-ray fluorescence. A significant linear relationship of rCBV = 6.26 (±0.47 SD) -0.015 (±0.004 SD) MABP was found. For each one torr change in the MABP, there is a change in rCBV of 0.015 cc/100 gm of brain tissue over a range of MABP of 35 to 200 torr. An additional observation of this investigation was that autoregulation of the cerebral blood flow (CBF) is perturbed for a period lasting up to 15 minutes after the intravenous injection of Renografin 76
R
.
VIII. Training, Education, Manpower, and Research for Stroke Care
Authors: GIFFORD RAY W. , BELL RODERIC M. , GILROY JOHN , GOLDSCHMIDT JOHN W. , GREENHOUSE ARNOLD H. , LEONE LUCILE P. , MCHENRY LAWRENCE C. , O'LEARY JAMES L. , POWERS LELAND E. , SCHATZ IRWIN J. , SCHWARTZ HENRY G. , STEARNS NORMAN S.
Published: June 2011

The manpower required for diagnosis and management of the 500,000 patients who experience stroke in the United States annually encompasses numerous disciplines, beginning with the family physician. The medical specialists and allied health personnel chiefly involved in addition are the neurologist, internist/cardiologist, nurse, physiatrist, physical therapist, occupational therapist, and speech therapist. Besides these, services of the radiologist, neurosurgeon, vascular surgeon, psychiatrist, orthopaedist, urologist, ophthalmologist, and pathologist frequently are needed. Important support is given by the dietitian, social worker, psychologist, and vocational rehabilitation counselor. Statistics are included for manpower available at present in a number of these disciplines.

Training and education extend throughout all levels, from the undergraduate through the postgraduate, and including continuing education. The knowledge and skills which each of these special groups should possess for competence in the area of stroke are described. The results of a survey are summarized, indicating the current status of stroke care in the curricula of United States medical schools and schools of osteopathy.

The concept of a stroke team is presented, describing the advantages of interdisciplinary action and effective utilization of available personnel and resources for patient care and for educational and training functions. An example is cited to demonstrate its feasibility and to illustrate the methods of establishing a local stroke program.

The list of research needs in the area of stroke is extensive--over 100 pertinent topics are cited. Recommendations of the study group are summarized.
Dexamethasone as Treatment in Cerebrovascular Disease. 2. A Controlled Study in Acute Cerebral Infarction
Authors: BAUER RAYMOND B. , TELLEZ HENRY
Published: June 2011

Fifty-four patients with acute cerebral infarction were included in a double-blind study to evaluate Decadron® as therapy. When comparison of patients with similar levels of consciousness was made, there was no significant difference between those patients receiving Decadron® and those receiving placebo therapy.

Three patients developed gastrointestinal tract bleeding in the placebo group, but there were none in the Decadron®-treated group.

There was no good correlation between the clinical state of the patient and the CSF pressure, either on admission or during the 14-day course of the study.
Cerebral Apoplexy (Stroke) Treated With or Without Prolonged Artificial Hyperventilation: 2. Cerebrospinal Fluid Acid-Base Balance and Intracranial Pressure
Authors: CHRISTENSEN M. STIG , BRODERSEN POUL , OLESEN JES , PAULSON OLAF B.
Published: June 2011

CSF acid-base changes and intracranial pressure (ICP) were studied in 50 patients with cerebral apoplexy (stroke) in the acute phase. Thirty-three of the patients were treated afterward with artificial hyperventilation for 72 hours (15 hypocapnic [Pa

CO

CO
2

25 mm Hg] and 18 normocapnic). The remaining 17 patients were breathing spontaneously throughout. Arterial P

CO

CO
2

, CSF lactate, pyruvate and bicarbonate and ICP were followed during the course.

Compared to a control group initial mean values showed significant increases of CSF lactate (2.36 mmol per liter) and pyruvate (0.183 mmol per liter) but with a normal lactate/pyruvate ratio (13.3), a reduced bicarbonate (22.0 mmol per liter), and reduced Pa

CO

CO
2

(34 mm Hg), indicating spontaneous hyperventilation. No correlation between the degree of initial hyperventilation or CSF lactate and the mortality rate was found. ICP averaged initially 15 mm Hg.

The untreated patients had almost unchanged CSF values and Pa

CO

CO
2

during the following six days. During induced and sustained hypocapnia and normocapnia, CSF bicarbonate slowly followed changes in Pa

CO

CO
2

with CSF pH tending to return toward normal. The time course of this CSF pH adaptation had an estimated half-time of about six hours, and was complete within 30 hours. A similar time course of changes induced in ICP by ventilation was observed.
Physiological Responses of Local Areas of the Cerebral Circulation in Experimental Primates Determined by the Method of Hydrogen Clearance
Authors: SYMON LINDSAY , PASZTOR EMIL , DORSCH N. W. C. , BRANSTON NEIL M.
Published: June 2011

The reactivity of cortex, putamen and white matter to changes in arterial CO
2
tension has been assessed. There was no significant difference between the CO
2
reactivity obtained for the three tissues which were in the region of 2% to 3.5% increase over basal blood flow per mm Hg P

CO

CO
2

increase. The data suggested a somewhat greater reactivity for white matter than for gray matter, though differences were not significant.

Excellent autoregulation to altered perfusion pressure, induced either by hemorrhage or by raising the intracranial pressure with cisternal infusion, was found in gray matter of cortex and putamen and in white matter. With reduction of perfusion pressure by both techniques, it appeared that zero blood flow could be more readily induced in white matter than in gray matter.

Autoregulatory curves to change in perfusion pressure obtained by either method seemed identical, suggesting that the mechanisms involved in the maintenance of cerebral blood flow in the face of reduced arterial pressure or rising intracranial pressure are the same.

Hyperemia was observed in all three areas of the cerebral circulation examined following the restoration of perfusion pressure after a period of reduction. No significant differences in the degree of hyperemia induced by similar stimuli were observed in these three sites.
Evidence for Abnormalities in Clotting and Thrombolysis as a Risk Factor For Stroke
Authors: PILGERAM LAURENCE O. , CHEE ANTHONY N. , VON DEM BUSSCHE GLENN
Published: June 2011

Four hundred six patients with ischemic thrombotic cerebrovascular disease (ITCVD) and 115 age-matched controls were studied to select risk factors which would identify ITCVD-prone individuals from a healthy population. The following factors were evaluated: soluble fibrin, plasminogen, plasminogen activator, fibrinogen, partial thromboplastin time, generation of thromboplastin, fibrin degradation products, triglycerides, type IV hyperlipoproteinemia, and cholesterol. Discriminate function analyses were used to select those risk factors which best separate and classify the ITCVD and control subjects. The primary risk factors are the activated partial thromboplastin time, soluble fibrin, fibrinogen, and plasminogen activator. Utilizing only these four primary risk factors in a discriminate function, 93.2% of the patients were correctly classified. Consideration of other variables increased still further the discriminate function.
The Outcome of Stroke at Hospital Discharge in New York City Blacks
Authors: SHAFER STEPHEN Q. , BRUUN BERTEL , RICHTER RALPH W.
Published: June 2011

Of 527 black patients admitted with new stroke to a municipal general hospital, 311 (59%) were discharged alive. Thirty-nine percent of survivors were independent with minimal or mild deficit. Thirty-two percent were independent with significant neurological deficit. Twenty-two percent were dependent, of whom half went home with special assistance and half to nursing homes. Five percent were transferred to a long-term rehabilitation hospital. These figures are similar to those from other races and settings. Stroke patients used more than 12,400 hospital days per year, at least 11% of all bed-days on the appropriate services. The average stay was 54 days for survivors, 22 days for fatal cases, and 45 days for all cases. The 28% of survivors who were severely disabled used 51% of all the hospital days, much of that time stable and awaiting transfer to long-term care. Such severely disabled patients comprise much of the growing burden of stroke on a community's resources. Expanding long-term care facilities for stroke patients is a social and economic necessity.
Cardiovascular Dimensions in Patients With Intracranial Arteriovenous Malformation
Authors: PERÄSALO JUHANI , WALTIMO OLLI , RICHTER TIMO HEISKANEN
Published: June 2011

The hemodynamics of 29 adult subjects with a congenital intracranial arteriovenous malformation were studied by radiocardiography. The cardiac index, heart rate, stroke index, systemic arterial pulse pressure and radiographical heart volume did not differ significantly from the normal. However, the total blood volume (P < 0.001) and the plasma volume (P < 0.05) were greater than normal.

The radiocardiograms of 17 patients were analyzed by analogue computer. The right heart blood volume (P < 0.05) and the left heart blood volume (P < 0.02) were above normal, but of equal magnitude. The pulmonary blood volume did not differ from the normal. The same was true of the respective volumes as percentages of the total blood volume. The cardiopulmonary (P < 0.01) and the peripheral (P < 0.005) blood volumes were greater than normal.

The results indicate that the major circulatory consequence of a congenital intracranial arteriovenous malformation is an increased circulating blood volume.

The size or the location of the malformation did not correlate with the hemodynamic parameters.
Management of Completed Strokes With Dextran 40. A Community Hospital Failure
Authors: SPUDIS EDWARD V. , de la TORRE ERNESTO , PIKULA LOUIS
Published: June 2011

Fifty-nine patients with onset of moderate to severe unimproving paralysis of less than 24 hours' duration were randomized into treatment (Dextran 40) and control groups, managed similarly except for the dextran. A strict effort to study a uniform cerebral process by rejecting patients with hypertension, insulin-dependent diabetes, potential emboli, and pulmonary or renal disease resulted in a small sample. Most patients considered for the study had begun to improve before the initial examination. All patients had spinal tap prior to the decision to randomize. Results were evaluated independently by the three authors over a three-week interval and tabulated after three years. A greater percentage of dextran-treated patients improved with respect to consciousness and strength in upper and lower extremities, but showed less restoration of language than the untreated patients. The differences in the two groups were not significant. One of 30 patients given dextran may have had a reaction.
Autoregulation and Hyperemia of Cerebral Blood Flow as Evaluated by Thermal Diffusion
Authors: CARTER L. PHILIP , ATKINSON JAMES R.
Published: June 2011

A thermal diffusion flow probe gave a quantitative dynamic recording of cerebral blood flow (CBF) during bleeding and transfusion in experimental animals. Autoregulation was readily demonstrated in nine of 12 animals and was found only with gradual hypotension. After autoregulation was lost, no increase in CBF could be obtained with carbon dioxide inhalation. Reactive hyperemia was demonstrated consistently following compromised CBF and, again, no increase in CBF with hypercarbia could be obtained until the hyperemia had subsided. Once hyperemia ceased, autoregulation could be demonstrated again in the same animal.
Cholinergic Mechanism in the Cerebrovascular Action of Carbon Dioxide
Authors: ROVERE ALFREDO A. , SCREMIN OSCAR U. , BERESI MARIA R. , RAYNALD AUGUST C. , GIARDINI ADOLFO
Published: June 2011

The effect of an increase in Pa

CO
CO2

on cortical blood flow was tested in control animals and after atropine or eserine administration. Blood flow was measured at the tip of implanted platinum electrodes by means of the hydrogen clearance method. The results showed that, although atropine did not impede the appearance of autoregulation, it completely blocked the increase in cortical blood flow associated to a step increase in Pa

CO
CO2

. The effect of CO
2
on cortical blood flow was significantly greater under eserine than in untreated controls.
Failures and Successes in a Stroke Program
Authors: DOW ROBERT S. , DICK H. LENOX , CROWELL FRED A.
Published: June 2011

The activities toward stroke prevention and improving stroke care at Good Samaritan Hospital and Medical Center of Portland, Oregon, for the past ten years are described. The program was multifaceted and included a stroke clinic, a stroke care unit, a course for nurses from throughout the state of Oregon and southwestern Washington, panel discussions and exhibits about stroke care, an educational program for families of stroke patients and satellite clinics at two small communities in Oregon.

The presence of this program changed the percentage of patients with strokes of equal severity going home from 13% to 58% at Good Samaritan Hospital and Medical Center and no similar trend could be detected in five other hospitals in Portland during a comparable period.

The evaluation of the program revealed that a team approach to stroke care in a special unit improved the care of stroke patients throughout the hospital and was effective in bringing the family into an active role in rehabilitation and patient care. The program also achieved educational goals.
Epidemiology of Stroke: Emphasis on Transient Cerebral Ischemic Attacks and Hypertension
Authors: WHISNANT JACK P.
Published: June 2011

The three factors other than age that are the most important determinants of stroke occurrence are (1) transient cerebral ischemic attacks (TIAs), (2) hypertension, and (3) cardiac disease.

In the Rochester population study, a stroke developed during the period of observation in 36% of the patients with TIAs. Fifty-one percent of all the strokes occurred during the first year after the TIA, and 21% occurred during the first month after the first attack.

Hypertensive persons have an increased incidence of each of the major atherothrombotic diseases as compared to normotensive persons.

During the full 25 years of study of the Rochester population, there was a decrease from the earliest to the latest five-year period of 32% for all strokes in women and 20% in men. This may reflect treatment of this population.
Regional Cerebral Blood Flow in Acute Stroke: Preliminary Experience With the
133
Xenon Inhalation Method
Authors: RAO N. S. , ALI Z. A. , OMAR H. M. , HALSEY J. H.
Published: June 2011

The
133
Xenon inhalation method of measuring regional cerebral blood flow was applied in serial studies comprising 100 measurements in 57 cases of acute hemiparesis and hemiplegia presumed due to arterial occlusion. Satisfactory data for analysis were obtained in over 95% of the cases studied. Significant flow reductions in the ischemic hemisphere were demonstrated in the cases with more severe clinical disability. This study demonstrates the feasibility of applying this method for serial regional cerebral blood flow measurements in most cases of acute stroke. The expected clinical usefulness and limitations of the method are discussed.
Cervical Carotid Imaging With a Continuous-Wave Doppler Flowmeter
Authors: SPENCER MERRILL P. , REID JOHN M. , DAVIS DONALD L. , PAULSON PAUL S.
Published: June 2011

A noninvasive technique for carotid arteriography using an ultrasonic directional Doppler flowmeter to image the carotid bifurcations is described. The technique uses a position sensing arm to hold the sharply focusing probe and translates the position of arterial flow onto an image storage screen. By multiple manual sweeps across the cervical carotids, a two-dimensional projection of the locus of arterial flow is developed. The probe beam is then applied through the eyelids to assess the posterior orbital ophthalmic flow. The adequacy of the internal carotid circulation and the presence of stenosis and calcified plaques are determined. Experience with the first 60 patients surveyed using the Doppler technique demonstrated a high degree of accuracy and reproducibility. The ultrasonic angiography provided local flow and velocity information that x-ray angiography did not. X-ray angiography is frequently indicated by the ultrasonic findings when risks of x-ray angiography might not otherwise be taken. The technique was found especially sensitive in detecting calcified atherosclerotic plaques and may be used in screening for the stroke-prone patient and following arterial lesions over extended periods of time.
Cerebral Metabolic Changes During Treatment of Subacute Cerebral Infarction by Alpha and Beta Adrenergic Blockade With Phenoxybenzamine and Propranolol
Authors: STIRLING JOHN , OKAMOTO SHIGEMICHI , SHIMAZU KUNIO , KOTO ATSUO , OHUCHI TADAO , SARI ATSUO , ERICSSON ARTHUR DALE
Published: June 2011

Cerebral hemispheric blood flow (HBF) and metabolism were measured in 30 patients with acute and subacute cerebral infarction before and after intracarotid infusion of the alpha adrenergic blocking agent phenoxybenzamine (PBZ) or the beta adrenergic blocker propranolol (PPL) dissolved in saline. Following intracarotid injection of 7 µg per kilogram per minute PBZ, HBF showed no change but cerebral hemispheric oxygen consumption (HMIO
2
) and carbon dioxide production (HMICO
2
) decreased. Glucose consumption (HMIGl) was unchanged but the glucose to oxygen utilization ratio (HG:O) increased. Intracarotid injection of 1.45 µg per kilogram per minute PPL caused reduction of HBF, HMIO
2
, HMICO
2
, HMIGl and HG:O. After PBZ infusion, mean systemic arterial blood pressure (MABP) decreased slightly, intracranial venous pressure (ICVP) and CSF pressure (CSFP) increased, and central venous pressure (CVP) remained unchanged. PPL infusion had no effect on intracranial dynamics.

Possible mechanisms whereby PBZ and PPL influence cerebral metabolism and function were discussed. Inhibition of uncoupling of oxidative phosphorylation appeared to be the most likely explanation for the improvement in brain function and metabolic change associated with each of the drugs. These data support the concept that catecholamines released into brain tissue are a possible cause of uncoupled oxidative phosphorylation.

Presently available evidence suggests that adrenergic blocking agents warrant clinical evaluation in the treatment of acute cerebral ischemia, infarction, hemorrhage, and anoxia.
Pathogenesis and Natural History of Transient Global Amnesia
Authors: MATHEW NINAN T. , MEYIR JOHN STIRLING
Published: June 2011

Fourteen patients aged between 49 and 92 years who had suffered from one or more attacks of transient global amnesia (TGA) have been followed for a mean interval of 30 months. Thirteen patients had one or more risk factors for cerebrovascular disease, such as hypertension, cardiac abnormalities, diabetes and hyperlipidemia. Clinical evidence for vertebrobasilar arterial insufficiency was demonstrated in 11 cases. EEG examination revealed bitemporal or bioccipital slow wave activity. Four-vessel arteriography showed atherosclerotic, stenotic, or occlusive lesions predominantly in the vertebrobasilar and posterior cerebral arterial systems. Five patients without recurrence of TGA showed no permanent impairment of memory, whereas eight who had recurrent attacks of TGA showed permanent memory impairment as well as mild visual-spatial or visual-motor dyspraxia as judged by neuropsychological tests on follow-up visits. "Amnesic stroke" with permanent and gross memory defect and dyspraxia occurred in two patients.

It is concluded that the majority of transient global amnesic episodes in the elderly or in those with the risk factors listed above result from cerebrovascular insufficiency particularly in the territory of vertebrobasilar and posterior cerebral arterial systems (which supply major portions of the ascending reticular activating system, parahippocampal-fornical-mamillary system, inferomedial aspects of the temporal lobe and occipital lobe). Repeated attacks of TGA are not rare and with each attack the likelihood increases of permanent memory deficits and progressive dementia. A rarer outcome is cerebral infarction in the territory of posterior cerebral arteries commonly referred to as "amnesic stroke."
Thromboelastographic Studies in Cerebral Infarction
Authors: ETTINGER MILTON G.
Published: June 2011

Blood coagulability in patients following cerebral infarction was studied utilizing the thromboelastograph (TEG). Cerebral infarction patients from two separate institutions were studied within 24 to 48 hours after onset of stroke. Ninety-four stroke patients from one institution and 109 from another yielded a total stroke population of 203 patients for this study. Fifty-nine age-matched normals were used as a control group. Frequency distribution curves were determined for a TEG ratio of ma/(r + k). The 59 controls exhibited a normal frequency distribution between the values of 1.6 and 4.0. Both groups of stroke patients revealed an increased number of patients with a ratio exceeding 4.0, suggesting a hypercoagulable state exists following cerebral infarction in approximately 29% to 38% of the patients studied.
Surgical Decompression for Cerebral and Cerebellar Infarcts
Authors: IVAMOTO HENRIQUE S. , NUMOTO MITSUO , PEARDON DONAGHY R. M.
Published: June 2011

Following an infarction in the right cerebral hemisphere, massive cerebral edema developed in a woman and led to a marked intracranial hypertension and to a progressive "uncal and central herniation." The downhill course was reverted with a decompressive operation. Epidural pressure was monitored during the procedure and in the postoperative period. She showed progressive recovery from the initial motor, sensory, and visual field losses. Among 18 reported patients with cerebral infarction who underwent surgical decompression, 11 presented pupillary asymmetry, 14 were in stupor or coma, and 18 were either hemiplegic or hemiparetic preoperatively. Seven died following the operation. Among four cases of cerebellar infarction who underwent similar procedures, there were three survivors. Due to the lack of a controlled study the data available so far are not conclusive as to the beneficial effects of surgical decompression for cerebral or cerebellar infarcts. Some data of clinical relevance on cerebral edema and intracranial hypertension associated with cerebral infarction are reviewed.
Cooperative Study of Intracranial Aneurysms and Subarachnoid Hemorrhage. Report on a Randomized Treatment Study
Authors: SAHS ADOLPH L.
Published: June 2011

Fifteen institutions participated in a cooperative study for treatment of single ruptured intracranial aneurysms. Between June, 1963, and February, 1970, 1,005 protocols were submitted to the Central Registry. All patients had a single ruptured aneurysm on the internal carotid, middle cerebral, anterior cerebral-anterior communicating or vertebral-basilar arteries. The four treatments allocated randomly were regulated bed rest, drug-induced hypotension, carotid ligation, and intracranial surgery. This study was an attempt to provide the relative merits of these several modes of therapy.
Respiratory Pattern Disturbances in Ischemic Cerebral Vascular Disease
Authors: LEE M. C. , KLASSEN A. C. , RESCH J. A.
Published: June 2011

Impedance pneumography was used to monitor respiratory rates and patterns in 49 patients with acute ischemic cerebral vascular disease. Nine patients had clinical evidence of bilateral ischemic cerebral disease. In one of these, normal respiratory pattern was present at all times; in five, there was intermittent Cheyne-Stokes respiration; in two, there were variants of Cheyne-Stokes pattern, and one patient eventually developed sustained tachypnea with probable hyperpnea. Twenty-eight patients had unilateral cerebral infarct. In five of these, normal respiratory pattern was present at all times; in 15, there was intermittent Cheyne-Stokes respiration; six had a variant of Cheyne-Stokes respiration; two had sustained tachypnea with probable hyperpnea. In 12 patients with brainstem infarcts, Cheyne-Stokes respiration was intermittently present in four, Cheyne-Stokes variant patterns were observed in two, and sustained tachypnea with probable hyperpnea developed in six. Abnormalities of respiratory patterns occurred more frequently during sleep, in the presence of a depressed sensorium, and in patients with severe neurological deficits. Respiratory alkalosis of variable degree was present in all patients with Cheyne-Stokes respiration or sustained tachypnea with probable hyperpnea. Cheyne-Stokes respiration was not always related to bilateral cerebral lesions. Intermittent Cheyne-Stokes respiration was not closely related to immediate prognosis. Sustained tachypnea with respiratory alkalosis was associated with the highest mortality rate among patients with respiratory pattern abnormalities.
Incidence and Early Prognosis of Stroke in Espoo-Kauniainen Area, Finland, in 1972
Authors: AHO KARI , FOGELHOLM RAINER
Published: June 2011

A stroke register has been operating in the Espoo-Kauniainen area, Finland, since January 1, 1972. The study population was 108,000 persons on January 1, 1972. In order to find totally new cases of stroke the following sources were utilized: hospitals and practicing physicians serving the study area were contacted regularly, death certificates were perused every two weeks, and copies of medical certificates or stroke patients applying for sick leave were received from The National Pensions Institute.

During 1972 a total of 153 new stroke cases were registered, giving an incidence of 142/100,000/year. The young age structure of the study population (5.2% were 65 years or older) explains this relatively low incidence. When applied to the total population of Finland and adjusted for age and sex the incidence is 231/100,000/year. The total cases were distributed equally between men and women. Men in age groups 50 to 59 and 60 to 69 years had an incidence twice that of women. The opposite was true in the age group 70 to 79 years. The incidence increased steeply with age.

Case fatality during the acute phase, the first three weeks, was 38% for all stroke cases. In the different clinical entities the case fatality was highest among intracerebral hemorrhages (66%) and lowest among ischemic cerebral infarction (27%).

The results of the first year of registry give an incidence of stroke for Finland which is relatively high compared with many earlier studies from other countries.
Role of Lipids in the Development of Brain Infarction: The Framingham Study
Authors: KANNEL WILLIAM B. , GORDON TAVIA , DAWBER THOMAS R.
Published: June 2011

An association of blood lipids with the development of atherothrombotic brain infarction under age 60 is demonstrated. This is based on 18 years' surveillance of 5,209 men and women, of whom 52 men and 59 women developed brain infarction. The relationship under age 60 was statistically significant only for men.

Triglyceride-rich pre-beta and cholesterol-rich beta lipoprotein were both related to the incidence of premature brain infarctions. Regardless of associated lipoprotein pattern, risk was proportional to serum cholesterol value, under age 60. On the other hand, pre-beta lipoprotein was unrelated to risk when associated cholesterol was taken into account.

At any lipid value risk of brain infarction varied greatly depending on the number and intensity of other contributors. Blood lipids are best considered as an ingredient of a stroke profile, and in the absence of other contributors to risk the influence of lipid is feeble.
Cerebral Autoregulation in Man
Authors: MCHENRY LAWRENCE C. , WEST JAMES W. , COOPER EDWARD S. , GOLDBERG HERBERT I. , JAFFE MARVIN E.
Published: June 2011

Autoregulation was tested by regional blood flow (rCBF) and cardiohemodynamic measurements before and after induced systemic arterial hypertension in 16 patients with varying neurological disorders. Hypertension was induced by increasing the arterial blood pressure by an intravenous infusion of Aramine. Seven (Group 1) of the patients had a mean increase in mean arterial pressure (MAP) of 32 mm Hg and had preserved autoregulation while nine (Group 2) with a 56 mm Hg increase in MAP showed complete or mixed loss of autoregulation. Group 1 had a higher baseline mean CBF than did the group with loss of autoregulation. The group with loss of autoregulation also generally had more severe involvement on the cerebral angiogram than did the other. Baseline cardiac index and cardiac work were lower in the group with loss of autoregulation. During Aramine infusion the MAP was increased by 38% in Group 1 and 59% in Group 2. The mean CBF was essentially unchanged in Group 1 but increased 24% in Group 2. When autoregulation is lost, rCBF may increase homogeneously or heterogeneously with some areas increasing while others remained unchanged or even decreased. In four instances there was an intracerebral steal during induced hypertension with a fall in rCBF. Whether or not autoregulation is preserved could be related to: (1) the greater induced increase in MAP in Group 2 than Group 1, (2) greater angiographical involvement with a lower baseline in CBF in Group 2 than in Group 1 or (3) a direct or indirect influence of various cardiovascular factors.
To-and-Fro Movement and External Escape of Carotid Arterial Blood in Brain Death Cases. A Doppler Ultrasonic Study
Authors: YONEDA SHOTARO , NISHIMOTO AKIFUMI , NUKADA TADAATSU , KURIYAMA YOSHIHIRO , KATSURADA KIKUSHI , ABE HIROSHI
Published: June 2011

In brain death cases who showed nonfilling phenomena in the internal carotid angiograms, the blood flow velocity patterns of the common carotid arteries were characterized by involvement of a single systolic peak and a marked reverse flow component which had never been observed in healthy subjects.

The individuality of each blood flow velocity pattern in the common, internal and external carotid arteries was made clear by placing the transducer in contact with the respective artery in a certain case. The Doppler signal from the internal carotid artery involving a signal from a reverse flow was slightly detectable, even if the blood pressure was elevated by norepinephrine infusion and the external carotid artery was temporarily compressed. The blood flow velocity pattern of the external carotid artery was similar to the pattern of the common carotid artery. The peculiar flow pattern indicates that a brain death case has a to-and-fro movement in the internal carotid blood flow and an external carotid escape of common carotid arterial blood.
Hypotension-Induced Changes in Cerebral Function During Cardiac Surgery
Authors: STOCKARD JAMES J. , BICKFORD REGINALD G. , MYERS ROBERT R. , AUNG MAUNG H. , DILLEY RALPH B. , SCHAUBLE JAMES F.
Published: June 2011

In a series of 75 patients undergoing cardiac operations with the assistance of cardiopulmonary bypass (CPB), 15 patients were subjected to relatively large hypotensive stresses during CPB as measured by the depth and duration of the fall in cerebral perfusion pressure. Of these 15 patients, eight manifested cerebral dysfunction postoperatively ranging from temporary exacerbation of pre-existing focal neurological deficits to irreversible coma. In each of these eight cases, EEG disturbances which first appeared at the time of hypotensive episodes during CPB persisted postoperatively and correlated with the nature and evolution of the clinical deficit. In two of the patients who did not regain consciousness postoperatively, neuropathological studies revealed bilateral laminar cortical necrosis, primarily involving cerebral cortex in one case and cerebellar cortex in the other, with accentuation in arterial border zones. Of seven other patients who suffered comparable exposures to hypotension during CPB, none evidenced cerebral dysfunction postoperatively. The most important determinants of this selective vulnerability to low extracorporeal perfusion pressure appeared to be the "reperfusion" pressure established after the hypotensive episode, postoperative blood pressure and cardiac output, and brain temperature at the time of the hypotension. Advanced age and history of cerebrovascular insufficiency were the greatest risk factors among patient variables.
Cerebral Energy Metabolism After Subarachnoid Hemorrhage
Authors: FEIN JACK M.
Published: June 2011

The purpose of this study was to determine the primary effects of subarachnoid hemorrhage (SAH) on cerebral oxidative metabolism and energy balance. Rhesus monkeys were prepared so that cerebral metabolic consumption rates of oxygen, glucose and the lactate/pyruvate ratios of CSF were estimated after isobarically and hyperbarically induced SAH. A regional analysis was performed on brain sections after similarly induced SAH in the rat, for levels of tissue, glucose, lactate, pyruvate, ATP, ADP, AMP, PCr and the partition of hexokinase between soluble and mitochondrial bound forms. The presence of intracranial hypertension was associated with an immediate ischemia, and increased cerebral glucose extraction was initially noted. Specific tissue substrate concentrations in rat brain indicated that fresh intracisternal hemorrhage is associated with decreased glycosis at a time when high energy phosphate levels are normal. It is concluded that intracranial hypertension hastens the onset of ischemia after SAH. SAH alone produces a decrease in cerebral energy requirements which secondarily depresses the rates of consumption of energy yielding substrates. The depression in metabolic rates may be mediated through a brain stem mechanism.
Experimental Study on the Genesis of Cerebral Vasospasm
Authors: WHITE RICHARD P. , HAGEN A. AINSWORTH , MORGAN HOWARD , DAWSON WILLIAM N. , ROBERTSON JAMES T.
Published: June 2011

The cerebral vasospasm produced by blood, fractions of blood, and blood-borne agents administered intracisternally was studied arteriographically to attain a better understanding of the genesis of vasospasm. The results indicate this phenomenon is multifarious in origin, involving a number of spasmogens. Whole blood, platelets, platelet extracts, some isolated components of platelets, plasma, thrombin, histamine, serotonin and prostaglandins F
1α
, E
2
and F
2α
produced a significant incidence and duration of spasm. Norepinephrine and prostaglandin E
1
were inactive. Spasm produced by arachidonic acid and red blood cells was of questionable significance.

Compared to whole blood, thrombin usually produced spasm which was more delayed in onset while most other active substances produced a shorter-lived spasm. However, among the pure substances tested, serotonin, prostaglandin E
2
and prostaglandin F
2α
induced spasm in small doses which most nearly resembled that observed with whole blood.

The hypothesis that the course of spasm depends upon synthesis of spasmogens by brain and blood is advanced. Prostaglandin synthesis plays a major role in this concept.
Effects of Excess NaCl Intake on Blood Pressure and Cholesterol-Induced Atherosclerosis in the Monkey
Authors: NAKAMURA MOTOOMI , MURAKAMI HIROAKI , SHIGEMI UMPEI
Published: June 2011

The
Macaca irus
is a monkey species that is highly susceptible to experimental cholesterol atherosclerosis of the aorta, coronary and cerebral arteries and cutaneous xanthomatosis-like lesions induced by feeding a diet high in cholesterol and/or coconut oil for 14 months.

The monkeys fed an atherogenic diet were divided into two groups: monkeys receiving excess sodium and controls. The excess sodium group showed a significantly higher systolic blood pressure as compared with the control group; however, elevation of blood pressure was mild and was not considered as significant hypertension.

The loading of excess sodium chloride in monkeys fed an atherogenic diet did not enhance severity of atherosclerosis of the aorta, coronary and cerebral arteries.
Hindbrain Stroke in Children Caused by Extracranial Vertebral Artery Trauma
Authors: FRASER RICHARD A. R. , ZIMBLER SEYMOUR M.
Published: June 2011

Hindbrain transient ischemic attacks (TIAs) culminating in posterior circulation stroke are described in five children. Atlanto-axial subluxation and angiographical documentation of C1 to C2 level arterial pathology are documented in one patient. Four additional patients with nearly identical clinical presentations, posterior fossa TIAs, stroke and basilar angiographical pathology are reviewed. A mechanical traumatic etiology is suggested.

Unexplained transient repeated brain stem and/or cerebellar symptomatology may be due to extracranial vertebral artery stenosis or occlusion by atlanto-axial instability. After appropriate documentation, stabilization may prevent further TIAs or strokes.
Pathological Studies on the Intracerebral and Retinal Arteries in Cerebrovascular and Noncerebrovascular Diseases
Authors: GOTO IKUO , KIMOTO KATSUHARU , KATSUKI SHIBANOSUKE , MIMATSU TAKAAKI , HIROSHI IKUI
Published: June 2011

Histological examinations of the intracerebral and retinal arteries were performed in patients who had cerebrovascular disease and in those cases who did not. Fibrinoid degeneration, fibrous nodule, and splitting, which are most frequently found in putamen, thalamus and pons, are thought to be the main changes in cerebral hemorrhage and infarction. Fibrous and fibro-hyalinoid thickenings of the retinal arteries were found mainly in the neighboring region of the optic disk, which reflects the changes of the intracerebral arteries. Hyalinoid thickening was found in the ora serrata, which does not reflect the changes of the intracerebral arteries.

Our results suggest that patients with these retinal artery changes in the region near the optic disk, if moderate to severe, have an increased risk of having or incurring cerebral hemorrhage and infarction, but the arterial changes in the ora serrata do not always indicate risk of cerebral hemorrhage and infarction.
Characteristics and Survival of Patients With Brain Stem Infarction
Authors: FOGELHOLM RAINER , AHO KARI
Published: June 2011

A retrospective study of 141 patients with ischemic brain stem infarction admitted to the Department of Neurology, University of Helsinki, during 1966 to 1973 was performed. The patients were contacted by mail in January and February, 1974; in case of death, the death certificates were procured. The follow-up period was from 4 to 99 months (median 46.5 months), during which a total of 39 patients had died. A life table analysis gave a 50% probability of a seven-year survival after the stroke. Survival was similar for men and women, and age appeared to have little influence on the prognosis with only a slightly higher case fatality in old age. Soft palate paralysis, disturbed sensorium, need of special treatment measures (feeding by gastric tube, intravenous infusions, etc.) during the acute phase, abnormalities in the ECG (T-wave negativity, S-T segment depression), fasting blood glucose 100 mg/100 ml or higher, and an abnormal EEG (slowing down of alpha rhythm alone or in association with paroxysmal and/or focal disturbances) were all associated with high case fatality. Preceding TIAs, blood pressure level, serum cholesterol and triglyceride values, and aortic arch angiogram findings, on the other hand, had no effect upon the prognosis. The effects of body build on prognosis remained obscure.
Carotid Arterial Supply of the Feline Brain
Authors: KAMIJYO YOSHINARI , GARCIA JULIO H.
Published: June 2011

A study of the supply to the feline brain by the carotid-middle cerebral arteries was conducted using in vivo transcardiac injection with a mixture of micropaque and carbon black. Modifications in the filling pattern of the arterial vessels were visualized following short-term occlusion of a middle cerebral artery. A modified surgical method to induce occlusion of the M-1 segment of the middle cerebral artery is also described.
Cardiac Arrhythmias and Sudden Death in Subarachnoid Hemorrhage
Authors: ESTANOL BRUNO V. , M.MARIN OSCAR S.
Published: June 2011

Life-threatening cardiac arrhythmias can occur in patients with subarachnoid hemorrhage secondary to rupture of intracranial aneurysms. The arrhythmias are secondary to acute dysfunction of the central nervous system and possibly to sudden increase in intracranial pressure. The autonomic nervous system is the mediator in the production of these disorders. The clinical significance of these rhythm disorders is discussed, particularly in regard to the sudden, unexpected death seen in this type of patient. The possible mechanisms of production are analyzed and their therapeutic implications are stressed.
A Paradoxical Cerebral Hemodynamic Effect of Hydralazine
Authors: OVERGAARD JØRN , SKINHØJ ERIK
Published: June 2011

Hydralazine is shown to have a very complex cerebral hemodynamic effect. It raises the intracranial pressure which, together with its effect upon systemic blood pressure, reduces the cerebral perfusion pressure. In spite of this and a concomitantly induced hyperventilation by hydralazine, CBF increases with some delay. The conclusion is that hydralazine is a cerebral vasodilator acting immediately upon cerebral capacitance vessels but later upon the resistance vessels as well.
Animal Model of TIA: An Experimental Study With Intracarotid ADP Infusion in Rabbits
Authors: FIESCHI C. , BATTISTINI N. , VOLANTE F. , ZANETTE E. , WEBER G. , PASSERO S.
Published: June 2011

Adenosine diphosphate (8 mg per minute for five minutes) was infused into the carotid artery of 63 rabbits. The effects were twofold: systemic hypotension and platelet aggregation in the cerebral circulation. As a consequence of the last effect, platelet emboli were produced which occluded cerebral arteries in a number and size sufficient to cause cerebral ischemia. Areas of focal ischemia were observed through a cranial window, and documented with antipyrine autoradiography.

Platelet thrombi were almost entirely transient, being fragmented and removed within a very short time of cessation of ADP infusion. Consequently, no permanent tissue damage ensued. This experimental model approaches the spontaneous transient ischemic attacks (TIAs) in man, demonstrating that these can be caused by pure platelet emboli.

A high cholesterol diet administered for two months prior to ADP infusion did not enhance the effect of the procedure or make the platelet aggregation and the following ischemia longer in duration or more severe.