bluuebunny/crossref_metadata_2025 huggingface dataset:
Range-gated pulsed Doppler power frequency spectrum analysis for the diagnosis of carotid arterial occlusive disease.
Authors: Harward T R , Bernstein E F , Fronek A
Published: June 2011

Carotid arterial disease was investigated with a Duplex Scanner using Power Frequency Spectrum Analysis. Sixty-one carotid systems were evaluated noninvasively and angiographically, while 20 controls were examined and assumed to be normal. Peak frequency and 50% frequency bandwidth, a quantitative index of spectral broadening, were correlated with the percentage of stenosis. Peak frequency predicted the presence or absence of hemodynamically significant stenoses (greater than or equal to 50% diameter reduction) with 90.8% accuracy, while 50% frequency bandwidth correctly identified similar lesions with 93.2% accuracy (p = NS). Also, with the latter results, carotid systems were grouped into less than 25%, 25% to 49%, and greater than or equal to 50% stenosis categories with an 86.4% accuracy. Similar statistical evaluation was attempted for peak frequency results. It was not possible to separate hemodynamically insignificant lesions (less than 50% diameter reduction) into distinct groups because of the overlap of results among those arteries with less than 50% stenosis. Finally, all eight occluded internal carotid arteries were identified with combined Doppler/imaging analysis. However, with imaging alone, only 5 of 8 (63%) occluded arteries were correctly identified.
Clinico-topographic correlation of small vertebrobasilar infarct using magnetic resonance imaging.
Authors: Bogousslavsky J , Fox A J , Barnett H J , Hachinski V C , Vinitski S , Carey L S
Published: June 2011

Neurological, CT and high-field (1.5T) magnetic resonance imaging (MRI) data were correlated in 6 patients previously clinically diagnosed as having suffered small vertebrobasilar infarct. MRI demonstrated infarcts in areas where CT was nearly always negative. MRI allowed very precise clinico-topographic correlations and appears to be the preferred imaging technique in vertebrobasilar infarcts.
Failure of central nervous system serotonin blockage to influence outcome in acute cerebral infarction. A double blind randomized trial.
Authors: Ramirez-Lessepas M , Patrick B K , Snyder B D , Lakatua D J
Published: June 2011

To determine the effect of blocking central nervous system (CNS) serotonin reuptake in the outcome of acute cerebral infarction (ACI), 49 patients were studied in a double blind, randomized trial. All patients suffered hemispheric ACI, were seen within 24 hours of onset, and were treated with low dose, subcutaneous heparin to prevent venous thrombosis; 25 received 10 mg. of trazodone hydrochloride intravenously every 12 hours for seven days and 24 were given an identically appearing placebo. To monitor trazodone effect, indol derivatives were measured in spinal fluid collected before and after treatment in 38 patients. Treatment and placebo patients had similar demographic characteristics, comparable risk factors, and neurologic deficit at onset. No appreciable difference was seen between treatment and control patients in regard to intercurrent events, degree of neurologic deficit, time of hospitalization, and mortality. Indol derivatives were consistently higher in the spinal fluid of trazodone patients after treatment, confirming serotonin reuptake blockage; however, this seems to have had no beneficial effect on the outcome of ACI.
Post-stroke depression: relationships to functional impairment, coping strategies, and rehabilitation outcome.
Authors: Sinyor D , Amato P , Kaloupek D G , Becker R , Goldenberg M , Coopersmith H
Published: June 2011

This study examined the phenomenon of post-stroke depression and evaluated its impact on rehabilitation outcome. Sixty-four patients presenting to a rehabilitation program within weeks of first stroke were evaluated for depression through self-report measures and staff ratings. Patients also rated the particular coping strategies which they used in dealing with their illness and hospital stay. Physical and occupational therapists provided measures of functional impairment at admission and discharge. A high (47%) prevalence of depression was found in this population, with no overall differences observed between patients with right or left hemisphere lesions. Depressed patients, in comparison to non-depressed, evidenced greater functional impairment at both admission and discharge. However, both groups showed similar gains over the course of rehabilitation. Coping strategies employed by depressed patients appeared to reflect a lower level of participation in the rehabilitation process. A subgroup of patients evaluated 6 weeks after discharge revealed that depression was associated with a worsening on one measure of functional status. These findings indicate that depression is a frequent companion of stroke, that it is associated with degree of functional impairment, and that it may exert a negative impact on the rehabilitation process and outcome.
Bilateral occlusion of the trunk of the middle cerebral artery. Results of an international randomized trial. The EC/IC Bypass Study Group.
Authors: Bogousslavsky J , Wong W , Barnett H J , Fox A J
Published: June 2011

Bilateral occlusion of the middle cerebral artery (MCA) trunk theoretically should be a very severe condition, but its actual prognosis has never been studied. Nine of 1,377 patients (7 Asians, 1 Black, 1 Caucasian) from the Cooperative Study of Extracranial/Intracranial Arterial Anastomosis were found to have atherosclerotic bilateral occlusion of the middle cerebral artery (MCA) trunk before entering the trial. Three presented with a stroke followed by a contralateral stroke, two experienced a unilateral stroke, two had a unilateral stroke preceded by ipsilateral TIAs, one had a unilateral stroke preceded by TIAs on both sides and one experienced isolated unilateral TIAs. Retrograde filling to the distal MCA was universally present. During follow-up (mean: 45 months), only one (non-operated) patient had further cerebrovascular events, and ultimately a fatal stroke. One additional patient died of sepsis and one had a silent myocardial infarct. All survivors resumed their previous activities. This study shows that in bilateral MCA trunk occlusion, the long-term prognosis is reasonable in the patients who do not present with a devastating stroke.
Urinary and gait disturbances as markers for early multi-infarct dementia.
Authors: Kotsoris H , Barclay L L , Kheyfets S , Hulyalkar A , Dougherty J
Published: June 2011

In a retrospective study of 84 outpatients with multiinfarct dementia, urinary and gait disturbances were found in 50% and 27%, respectively, and often preceded dementia and discrete stroke-like episodes by more than 5 years. Compared to patients without urinary disturbance, those with urinary dysfunction were predominantly male and more behaviorally impaired, but were similar in age, cognitive score, depression score, computerized tomography findings, and relative survival. Compared to patients without gait disturbance, those with gait abnormality had a higher Hachinski ischemic score and depression score and were more behaviorally impaired. Urinary and gait abnormalities may be markers for cerebrovascular disease and vascular dementia even in the absence of frank stroke. Damage to bifrontal outflow tracts may be the common pathophysiological mechanism underlying the behavioral and motor symptoms characteristic of vascular dementias.
Water extraction fraction and permeability-surface product after intravenous injection in rats.
Authors: Takagi S , Ehara K , Finn R D
Published: June 2011

A quantitative method has been developed to measure the water extraction fraction of rat brain after successive intravenous bolus injections of [15O]water and [11C]butanol based on a mathematical equation developed by the authors. This new method is noninvasive to the brain or craniocervical large vessels and does not require sacrifice of the rats. Arterial concentration curves and total head counts were measured in 8 rats by means of external coincidence detectors. Water extraction fraction in rat brain was 0.67 +/- 0.13 (mean +/- SD) and permeability-surface product was 1.75 ml/g min, where cerebral blood flow and arterial carbon dioxide tension were 1.71 +/- 0.86 ml/g min and 44.8 +/- 14.0 mm Hg, respectively. Water extraction fraction was stable with different measurement times from 20 to 80 seconds.
Pathophysiologic study of chronic infarcts with I-123 isopropyl iodo-amphetamine (IMP): the importance of periinfarct area.
Authors: Raynaud C , Rancurel G , Samson Y , Baron J C , Soucy J P , Kieffer E , Cabanis E , Majdalani A , Ricard S , Bardy A
Published: June 2011

Seventeen chronic cerebral infarcts were investigated by a highly sensitive, dedicated brain single photon emission computerized tomography system using 123I-isopropyl iodoamphetamine (IMP) and 133Xe. IMP uptake was measured 10 minutes, 2 hours, and 5 hours after injection, and regional cerebral blood flow was measured with 133Xe. In 4 cases a positron emission tomography system was used to measure the rCBF and the regional metabolic rate of oxygen with C15O2 and 15O2. The results obtained allowed us to identify 2 abnormal zones. One, the "central area," was characterized by a severe decrease in IMP uptake and rCBF averaging 34% and 46% respectively and by a hypodense image on the x-ray computerized tomography scan. The second, the periinfarct or "peripheral area" was characterized by a moderate decrease in IMP uptake and regional cerebral blood flow averaging 13 and 19% respectively; this area extended around the central area and had a normal density on computerized tomography scan. The IMP hypofixation of the peripheral area observed at the 10th minute tended to disappear at the 5th hour. The volume of this area was often found to be quite large, covering more than 30% of a hemisphere whereas the central area did not exceed 25%. Volume appeared to be correlated with the neurological status of the patient. The nature of the peripheral area is not established with certainty. It may be caused by deafferentation of areas not directly affected by the ischemic insult and/or selective ischemic neuronal loss. The results stress the important role played by the peripheral area, which may be useful in establishing the prognosis and evaluating the efficacy of therapy in individual stroke cases.
Can raising cerebral blood flow improve outcome after acute cerebral infarction?
Authors: Grotta J C
Published: June 2011

Cerebral blood flow correlates poorly with outcome after stroke, and most therapies aimed at increasing cerebral perfusion have not succeeded in predictably reducing neurological deficit. Newer approaches such as hemodilution and thrombolysis may prove to be more effective but might be most advantageous if combined with efforts to correct postischemic disturbances in cellular metabolism.
Effect of ketamine on cerebral cortical blood flow and metabolism in rabbits.
Authors: Oren R E , Rasool N A , Rubinstein E H
Published: June 2011

The effects of intravenous ketamine (1 mg/kg) on cerebral cortical blood flow and O2 uptake were evaluated in 13 anesthetized, ventilated rabbits. Blood flow was measured either directly (Group 1) or by the H2 clearance method (Group 2). In those animals of Groups 1 and 2 with normal control arterial pH (pHa), ketamine produced a significant increase in cerebral cortical blood flow of 18 and 34%, respectively, but had no effect on cerebral cortical O2 uptake. However, in rabbits with low control pHa, ketamine caused an increase in blood flow (30%) accompanied by a significant increase in O2 uptake (22%). Ketamine produced nonsignificant changes in mean arterial blood pressure and arterial blood gases, except for a significant reduction in pressure in animals with low pHa. It is concluded that ketamine is a cerebral vasodilator without cerebral metabolic effect when mean arterial blood pressure and arterial PCO2, PO2, and pH are held constant at physiologic levels. The vasodilator effect of ketamine is probably due to direct dilating action or activation of a cholinergic cerebral vasodilator system.
Ischemia in normo- and hyperglycemic rats: effects on brain water and electrolytes.
Authors: Warner D S , Smith M L , Siesjö B K
Published: June 2011

Previous investigations have shown that preischemic hyperglycemia worsens cerebral outcome. This study sought to delineate the temporal relations between postischemic brain edema and the development of spontaneous epileptic activity. Fasted rats were subjected to 10 minutes of forebrain ischemia. One-half of the animals were made hyperglycemic by glucose infusion prior to ischemia. At serial recirculation intervals regional specific gravity and cortical electrolytes were measured. Normoglycemic animals showed a biphasic increase in brain water content that was fully resolved by 96 hours and had no convulsive activities. Hyperglycemic brains, although displaying a slower resolution from an initial transient decrease in specific gravity, also developed an interval with normal water content that persisted at 18 hours postischemia. At 24 hours, an increase in water content recurred and was soon followed by the onset of seizure activity. Cortical electrolyte changes were unremarkable until seizures occurred. Significant increases in total Na+, Cl-, and Ca2+ and a decrease in K+ were then seen. We conclude that while the normoglycemic brain is capable of resolving postischemic edema in this model, the hyperglycemic brain develops a delayed secondary increase in water content followed by the onset of seizure activity accompanied by a deterioration of ionic homeostasis.
Cerebral effects of extended hyperventilation in unanesthetized goats.
Authors: Albrecht R F , Miletich D J , Ruttle M
Published: June 2011

Thirty-six adult, male unanesthetized goats were hyperventilated to a PaCO2 level of 16-18 mm Hg for 6 hours. Arterial and sagittal sinus blood and cerebrospinal fluid were analyzed for pH, blood gases, bicarbonate, lactate, and pyruvate before hyperventilation, during hyperventilation, and after the termination of hyperventilation. Total cerebral blood flow, regional brain blood flows, and cerebral metabolic rate for oxygen were calculated from the distribution of radioactive microspheres. Intracranial pressure was measured in either the right or left cerebral ventricle. With the initiation of hyperventilation, cerebral blood flow and cerebral metabolic rate for oxygen fell significantly (64 +/- 5 ml/100 g/min to 41 +/- 3; 4.6 +/- 0.3 ml O2/100 g/min to 3.6 +/- 0.2), but both returned to prehyperventilation values within 6 hours of hyperventilation. With termination of hyperventilation, cerebral blood flow and cerebral metabolic rate for oxygen increased significantly above control levels (64 +/- 5 vs. 105 +/- 9; 4.6 +/- 0.3 vs. 5.4 +/- 0.4). Intracranial pressure was unaffected by hyperventilation or its termination. Arterial and sagittal sinus blood and cerebrospinal fluid pH increased with hyperventilation but returned to control values by 6 hours. However, pH was still significantly elevated at 6 hours. Lactate and pyruvate followed a similar pattern except in the cerebrospinal fluid, where both increased throughout the course of hyperventilation. There were no significant differences in the lactate:pyruvate ratio. On termination of hyperventilation, pH of the arterial and sagittal sinus blood and cerebrospinal fluid fell below control levels. Bicarbonate values decreased in all fluid compartments and were still below control values 2 hours after the cessation of hyperventilation.(ABSTRACT TRUNCATED AT 250 WORDS)
Brain magnetic resonance imaging in the evaluation of lacunar stroke.
Authors: Rothrock J F , Lyden P D , Hesselink J R , Brown J J , Healy M E
Published: June 2011

Thirty-one patients with presumed lacunar stroke, recent (18 patients) or remote (13 patients), were evaluated with brain magnetic resonance imaging (MRI). MRI detected small, deep lesions appropriate to symptoms in 23 of the patients (74%) and was diagnostically superior to brain computed tomography (CT) in those cases where both studies were obtained acutely. MRI also appeared useful in distinguishing between acute and chronic ischemic lesions. Especially in the setting of suspected acute lacunar infarction, MRI, when available, should replace CT as the diagnostic imaging procedure of choice.
Spontaneous internal jugular vein thrombosis and venous-stasis retinopathy.
Authors: Gutteridge I F , Royle J P , Cockburn D M
Published: June 2011

A case is presented in-which the detection of venous-stasis retinopathy in one eye led to investigation of the carotid circulation. There were no neurologic symptoms of carotid insufficiency, and noninvasive tests failed to reveal significant carotid pathology. Digital subtraction angiography and carotid angiography demonstrated a carotid plaque of doubtful significance. At carotid endarterectomy, the venous-stasis retinopathy was found to be associated with venous thrombosis distant from the eye and in the internal jugular vein. This site is beyond the range over which isolated ocular vascular effects would be expected and was thought to be unrelated to the hemodynamically insignificant, nonulcerated carotid artery plaque. The possibility of this association being causal is discussed.
Transient cerebral ischemic attacks in a Japanese community, Hisayama, Japan.
Authors: Ueda K , Kiyohara Y , Hasuo Y , Yanai T , Kawano H , Wada J , Kato I , Kajiwara E , Omae T , Fujishima M
Published: June 2011

During a 20-year follow-up of 1,621 men and women aged 40 and over in Hisayama, Japan, 18 were found to have suffered transient cerebral ischemic attacks (TIAs) determined by clinical symptoms based on criteria proposed by the US Joint Committee for Stroke Facilities. The average annual incidence rate for the first TIA was 0.56 per 1,000 residents. Age and high blood pressure were strong determinants of TIAs for men. Nine of the 18 cases with TIAs (50%) subsequently developed cerebral infarction, an incidence significantly higher than that in the 1,603 subjects without TIAs (10.9%). Lacunar infarcts were most commonly found on pathologic examination of patients with TIAs who had had a subsequent stroke.
Contralateral flow reduction in unilateral stroke: evidence for transhemispheric diaschisis.
Authors: Lagrèze H L , Levine R L , Pedula K L , Nickles R J , Sunderland J S , Rowe B R
Published: June 2011

Using clinical presentation, angiography, computed tomography, and nuclear magnetic resonance imaging, 7 patients were identified who had strictly unilateral hemispheric infarction and unilateral cerebrovascular disease. In 6, cerebral blood flow measured by fluorine-18-fluoromethane inhalation and positron emission tomography was reduced in the contralateral hemisphere (p less than 0.05). Multiple regression analysis demonstrated a high correlation between contralateral flow reduction and the degree of flow impairment in the infarcted area (r = 0.941, p = 0.0014) but not with age, risk factor profile, blood pressure, PCO2, hematocrit, or duration of stroke. We conclude that transhemispheric diaschisis best explains the contralateral flow reduction seen in supratentorial ischemic stroke.
Measurement variability of carotid atherosclerosis: real-time (B-mode) ultrasonography and angiography.
Authors: O'Leary D H , Bryan F A , Goodison M W , Rifkin M D , Gramiak R , Ball M , Bond M G , Dunn R A , Goldberg B B , Toole J F
Published: June 2011

To quantify the within- and between-reader agreement of carotid B-mode ultrasonography and angiography interpretation, images from 117 patients examined by both modalities were read multiple times. Angiographic measurements were more reproducible than those of B-mode scans for all parameters except lesion width, but variations for B-mode scan measurements were similar to those for angiographic measurements. Within-reader agreement on the presence of ulceration was substantial for both modalities, whereas between-reader agreement was poor for B-mode scan and only moderate for angiography.
Risk factors for extracranial carotid artery atherosclerosis.
Authors: Crouse J R , Toole J F , McKinney W M , Dignan M B , Howard G , Kahl F R , McMahan M R , Harpold G H
Published: June 2011

We related risk factors, cardiovascular symptoms, and coronary status to the extent of extracranial carotid atherosclerosis as measured by B-mode ultrasonography in 376 volunteers hospitalized for elective coronary angiography. In a first analysis, we correlated risk factors and cardiovascular symptoms with carotid atherosclerosis. Univariate analysis showed that relations between many continuous risk factors and carotid atherosclerosis were graded and consistent for men and women. Multivariate analysis identified 6 significant variables (age, hypertension, pack-years smoked, and inversely, plasma concentrations of high density lipoprotein cholesterol and uric acid, and Framingham Type A score) that together accounted for 35% of the variability in extent of carotid atherosclerosis. In a second multivariate analysis, addition of coronary status (presence or absence of coronary stenosis as evaluated by coronary angiography) to the roster of candidate independent variables produced a new equation that accounted for an additional 5% of the variability in carotid atherosclerosis extent. Although much of the variability in extent of carotid atherosclerosis remains unexplained, these data define an association between coronary and carotid atherosclerosis that depends partly on shared exposure of both arteries to the same risk factors. They are also consistent with the concept that as yet undiscovered risk factors and/or genetic (e.g., arterial wall) factors common to both arterial beds also contribute to the relation between coronary and carotid atherosclerosis in human beings.
Clinical events following neuroangiography: a prospective study.
Authors: Dion J E , Gates P C , Fox A J , Barnett H J , Blom R J
Published: June 2011

Clinical events following cerebral angiography were prospectively evaluated in 1,002 procedures. The ischemic event rate between 0 and 24 hours was 1.3% (0.1% permanent). This incidence was higher (2.5%) in patients investigated for cerebrovascular disease, but the difference was not significant. In addition, 1.8% of the patients suffered ischemia (0.3% permanent) between 24 and 72 hours after angiography. Cerebral ischemic events occurred as a recurrence or worsening of a preexisting phenomenon. twice as often as de novo. All permanent ischemia was a worsening of a preexisting phenomenon. There was a significant increase in the incidence of neurologic events between 0 and 24 hours when the procedure lasted longer than 60 minutes and when there was systolic hypertension. Trends toward higher incidence were noted with the use of increased volume of contrast, with increased serum creatinine, when transient ischemic attacks or stroke were the indications, and when 3 or more catheters were used. The incidence of neurologic events between 24 and 72 hours increased significantly with the increase in the amount of contrast used, with age, and with diabetes. The occurrence of nonneurologic events (mostly hematomas) was significantly increased by multiple factors. This study shows that events can and do occur beyond the usual observation period of 24 hours but confirms the low risk of cerebral angiography when performed judiciously.
Carotid body tumor: unusual cause of transient ischemic attacks.
Authors: Chamorro Sanchez A , Varela de Seijas E , Matesanz Matesanz J , Trapero V L
Published: June 2011

Carotid body tumors are an unusual cause of transient ischemic attacks. The cases reported in the literature have been limited to the postoperative period. We report a patient with bilateral carotid body tumors and transient ischemic attacks as the presenting syndrome. A low-perfusion state could explain his symptomatology.
Local embolism from vertebral artery occlusion.
Authors: Pessin M S , Daneault N , Kwan E S , Eisengart M A , Caplan L R
Published: June 2011

Basilar artery territory stroke may result from embolism arising from the site of vertebral artery occlusion. This stroke mechanism (local embolism) has been well documented in the middle cerebral artery territory from extracranial internal carotid artery disease but not fully appreciated in the vertebral basilar circulation. We report two patients whose clinical presentation indicated major basilar artery territory infarction documented by angiography to be the result of vertebral artery occlusion and artery-to-artery embolism. Vertebral artery occlusion has often been associated with a benign course, but under certain circumstances embolism to the basilar artery may complicate the outcome.
Prevalence of stroke in the Parsi community of Bombay.
Authors: Bharucha N E , Bharucha E P , Bharucha A E , Bhise A V , Schoenberg B S
Published: June 2011

A door-to-door survey of 14,010 Parsis living in colonies in Bombay, India, screened people for possible neurologic diseases. High school graduates, social workers, and a medical student administered a questionnaire that had been shown in a pilot study to have a sensitivity of 100% for identifying persons with stroke. Neurologists used defined diagnostic criteria to evaluate those who were positive on the screening survey. One hundred eighteen persons (57 men, 61 women) suffered from stroke (842.3 cases/100,000 population). The age-specific prevalence ratios increased with age for both sexes and for each age group. Age-adjusted prevalence ratios were slightly higher for men than for women. The most common type of stroke was ischemic (114 cases).
Combination of aminocaproic acid and nicardipine in treatment of aneurysmal subarachnoid hemorrhage.
Authors: Beck D W , Adams H P , Flamm E S , Godersky J C , Loftus C M
Published: June 2011

Antifibrinolytic drugs reduce the risk of rebleeding during the first 2 weeks after aneurysmal subarachnoid hemorrhage. However, they do not lower overall mortality, largely because of an increased incidence of cerebral ischemia. The usefulness of antifibrinolytic drugs might be increased if a method to prevent or control vasospasm in patients were to be developed. We recently completed late Phase I and Phase II studies of the calcium ion blocking drug nicardipine in 67 patients treated within 1 week of subarachnoid hemorrhage. Of these 67 patients, 42 had delayed operations and were treated concomitantly with the antifibrinolytic drug aminocaproic acid (1.5 g/hr) for an average of 6 days before surgery. The outcome of these 42 patients is the subject of this report. Fifteen of 42 patients were treated with the lower dosage levels of nicardipine (0.4-4.5 mg/m2/hr), and 27 patients were treated at the highest dosage level (6.0 mg/m2/hr). Using the World Federation of Neurological Surgeons scale for subarachnoid hemorrhage, at admission 18 patients were Grade I, 15 were Grade II, 6 were Grade III, and 3 were Grade IV. Five patients (12%) developed clinical signs of deterioration suggestive of cerebral ischemia with concomitant evidence of vasospasm on arteriography. These patients were all treated with hypervolemic hypertensive therapy. Only one patient (2%) developed an infarction from vasospasm. Two patients developed symptomatic hydrocephalus requiring ventriculoperitoneal shunting, and a third patient required a temporary ventriculostomy. The 3-month postoperative outcomes were excellent. Three patients (7%) rebled. Three patients died, two from rebleeding of the aneurysm and one who never regained consciousness from the initial hemorrhage.(ABSTRACT TRUNCATED AT 250 WORDS)
Leukocyte response in patients suffering from acute stroke.
Authors: Violi F , Rasura M , Alessandri C , Intiso D , Germani M , Servi M , Fieschi C , Balsano F
Published: June 2011

The oxidation of adrenaline to adrenochrome has been shown to reflect the activation of leukocytes in vivo. We tested the in vivo activation of leukocytes by measuring plasma oxidation of adrenaline to adrenochrome in patients suffering from cerebral ischemia, cerebral hemorrhage, and transient ischemic attacks and in healthy subjects. Patients with cerebral ischemia and cerebral hemorrhage had significantly higher values than healthy subjects, while patients with transient ischemic attacks had values similar to those of healthy subjects. In some patients with cerebral ischemia, the test was repeated 4 and 15 days after the acute event, but the follow-up data did not differ from baseline values. Our study shows that leukocyte activation occurs in cerebral ischemia and cerebral hemorrhage.
Global cerebral ischemia and intracellular pH during hyperglycemia and hypoglycemia in cats.
Authors: Chopp M , Welch K M , Tidwell C D , Helpern J A
Published: June 2011

In 27 cats treated to vary arterial serum glucose concentrations, we measured cerebral high-energy phosphate metabolite concentration and intracellular pH using in vivo phosphorus-31 nuclear magnetic resonance spectroscopy during transient global cerebral ischemia and reperfusion. Hypoglycemia was induced with 4 units/kg i.v. insulin in six cats before ischemia; hyperglycemia was induced with 1.5 g/kg i.v. glucose in six cats before and in six cats during ischemia. Nine untreated cats subjected to ischemia without manipulation of blood glucose concentration served as controls. During ischemia, intracellular pH fell to similar levels in the control and both hyperglycemic groups. During reperfusion, the hyperglycemic before ischemia group initially exhibited a severe further decline in intracellular pH (p less than 0.003); this further decline was not observed in the control or the hyperglycemic during ischemia groups. Intracellular acidosis was attenuated both during ischemia and early after reperfusion in the hypoglycemic before ischemia group. In all groups, cerebral high-energy phosphate metabolite concentrations were depleted during ischemia and then recovered to the same degree during reperfusion. Our data suggest that brain glucose stores before ischemia determine the severity and time course of intracellular acidosis during ischemia and reperfusion.
Postinfarction seizures. A clinical study.
Authors: Gupta S R , Naheedy M H , Elias D , Rubino F A
Published: June 2011

We retrospectively studied 90 patients with postinfarction seizures to determine the clinical features (onset, number, type), prognosis, and electroencephalographic and computed tomographic findings; we included infarctions of all etiologies. Thirty-three percent of the 90 seizures appeared early (within 2 weeks after the infarction), and 90% of the 30 early seizures appeared within 24 hours after the infarction. Seventy-three percent of the 90 seizures occurred within the first year, and only 2% occurred greater than 2 years after the infarction. Fifty-six percent of the 90 seizures were single, and status epilepticus was seen in only 8%. Early-onset seizures were more likely to be partial (57% of 30); late-onset seizures were more likely to be generalized (65% of 60). Thirty-nine percent of the 90 initial seizures recurred, and there was no significant difference in recurrence rate between early- or late-onset initial seizures. Twenty-two percent of the 90 initial seizures became multiple recurrent seizures, and we could identify a precipitating factor in 86% of the 35 recurrent seizures. The most common electroencephalographic abnormality in the 61 patients so examined was focal slowing (61%), but recurrent seizures occurred in 100% of the four patients with periodic lateralized epileptiform discharges and in 75% of the eight patients with diffuse slowing. Computed tomography in 61 patients showed that large infarctions were associated with early (p less than 0.021) and multiple (p less than 0.05) seizures. Deep infarctions on computed tomograms (cortical infarctions extending to subcortical structures) tended to cause recurrent seizures (p less than 0.057). Seizures in 88% of the 90 patients could be managed with monotherapy.
Carotid endarterectomy: to shunt or not to shunt.
Authors: Gumerlock M K , Neuwelt E A
Published: June 2011

Because of controversies in the cerebrovascular literature regarding the use of an intraluminal shunt in carotid endarterectomy, we report a randomized prospective study of 118 consecutive symptomatic patients receiving surgery within a single neurosurgical practice. Over 4 years, 138 carotid endarterectomies were performed in the 118 patients, 63 operations with intraluminal shunting and 75 without. Standard rationale for surgery included ipsilateral cerebral infarction in 38% of the operations and ipsilateral transient ischemic attacks in 36%. Unilateral angiographic stenosis of greater than 90% was seen in 58% of the operations; there were no ipsilateral occlusions. Surgery was performed under general anesthesia with barbiturate induction and mild blood pressure elevation. The 30-day complication rate included a mortality rate of 0.7% with a 5.1% incidence of postoperative neurologic deficit and a 1.4% rate of myocardial infarction. In the 24 hours after surgery there were no cerebral infarctions in the shunted group and six in the unshunted group. This 8% rate in the unshunted group compared with 0% in the shunted group was significant at p = 0.023 with a power of 0.95 by Fisher's exact test and chi 2 analysis. This suggests that in our neurosurgical practice (resident training program) the use of an intraluminal shunt during carotid endarterectomy significantly reduces the risk of intraoperative neurologic deficit without increasing the incidence of other complications.
Comparison of spontaneously recovered versus nonrecovered patients with poststroke depression.
Authors: Starkstein S E , Robinson R G , Price T R
Published: June 2011

We followed 16 patients who developed depression immediately after a stroke for 6 months. By that time, six patients showed no depression (recovered group), while 10 patients were still depressed (nonrecovered group). There were no significant differences in demographic variables and social functioning between the groups, but the nonrecovered group showed less improvement in cognitive function and more physical impairments. Patients in the nonrecovered group had mainly cortical lesions, while those in the recovered group had mainly subcortical and posterior circulation strokes.
Pulsed Doppler assessment of innominate artery obstructive diseases.
Authors: Rautenberg W , Hennerici M
Published: June 2011

In 14 patients with severe stenosis or occlusion of the innominate artery a new high-energy, low-frequency (2 MHz) pulsed Doppler ultrasound method was used to investigate blood flow velocity patterns of both intrathoracic and intracranial cerebral arteries. Direct acquisition and evaluation of the innominate artery at its origin near the aortic arch enabled separation of it from adjacent arteries and reliable differentiation of stenosis from occlusion. Transcranial recordings from the basal cerebral arteries showed abnormal Doppler signals in 12 patients (86%). Among these abnormalities, observation of a latent steal phenomenon was closely related to the prevalence of cerebrovascular events. This latent steal phenomenon was characterized by a transient reduction of orthograde blood flow in the ipsilateral anterior, middle, and posterior cerebral arteries or in the basilar artery during postischemic hyperemia of the upper extremities. The predictive value of the latent steal phenomenon for the management and follow-up of asymptomatic patients with severe innominate artery obstructions is discussed.
Lower cranial nerve palsies due to internal carotid dissection.
Authors: Waespe W , Niesper J , Imhof H G , Valavanis A
Published: June 2011

A 41-year-old man experienced intense headache and neck pain, bruits, and a complete unilateral cranial nerve palsy IX-XII (Collet-Sicard syndrome) after a trivial back trauma. Magnetic resonance imaging and angiography demonstrated features of bilateral internal carotid artery dissection with aneurysm formation at the base of the skull compressing the nerves at the level of the jugular foramen. Severe dysphagia persisted for 1 month but rapidly improved after occlusion of the carotid aneurysm with a detachable balloon.
Segmental duplication of the basilar artery with thrombosis.
Authors: Berry A D , Kepes J J , Wetzel M D
Published: June 2011

Duplication or fenestration of the basilar artery, a result of an embryologic malformation, has an incidence of up to 5.3% in the general population. The most common complication of this anomaly is the formation of aneurysms. Thrombosis of a partially duplicated basilar artery developed in a 43-year-old man who complained of visual disturbances followed by seizures and coma, and who eventually died. Autopsy showed a partially organized thrombus occluding both halves of a duplicated portion of the basilar artery, old infarcts in the calcarine cortices, and a recent large infarct in the basis pontis. There was only minimal atherosclerosis of other intracranial arteries, including the vertebral arteries. Hemodynamic disturbances and turbulent blood flow at the site of fenestration may be the cause of the thrombosis that occurred in this artery.
Prediction of stroke before and after unilateral occlusion of the common carotid artery in gerbils.
Authors: Matsumoto M , Hatakeyama T , Akai F , Brengman J M , Yanagihara T
Published: June 2011

A method was developed to predict the severity of cerebral ischemia before permanent occlusion of a common carotid artery in gerbils by observing the diameter and appearance of the artery after temporary occlusion and observing clinical signs after permanent occlusion. The severity of cerebral ischemia was confirmed by a sensitive immunohistochemical method and measurement of focal cerebral blood flow after 30 minutes' ischemia. All gerbils with greater than 40% reduction of the diameter and a white arterial margin distal to temporary occlusion developed severe neurologic signs following permanent occlusion, but no gerbils with reduction of less than 30% and a red arterial margin developed neurologic signs. With the cumulative neurologic score, gerbils could be divided into classes with no, mild, moderate, and severe symptoms, mostly after 10 minutes. Severely symptomatic gerbils were identified in 3 minutes. Extensive ischemic damage was observed in severely symptomatic gerbils, but no immunohistochemical lesion was detected in mildly symptomatic gerbils. Cerebral blood flow was markedly reduced in severely symptomatic gerbils but more selectively reduced in the cortical structures of moderately symptomatic gerbils. This prediction method is useful for investigating early cerebral ischemia and for evaluating the effectiveness of pharmacologic agents.
Bilateral posterior cerebral artery strokes in a young migraine sufferer.
Authors: Moen M , Levine S R , Newman D S , Dull-Baird A , Brown G G , Welch K M
Published: June 2011

We report a young migraine sufferer who developed bilateral posterior cerebral artery territory infarcts during the course of his classic migraines, the second of which was associated with intraluminal clot in the posterior cerebral artery. To our knowledge, bilateral posterior cerebral artery stroke from spontaneous migraine has not been reported. Head computed tomographic, magnetic resonance imaging, and angiographic correlation is presented. The mechanism of migrainous infarction may be in part explained by caliber changes in arterioles and capillaries leading to flow reduction in the more proximal conduit arteries combined with the associated coagulopathy that has been previously documented during migraine attacks.
Intellectual impairment and cerebral lesions in multiple cerebral infarcts. A clinical-computed tomography study.
Authors: Loeb C , Gandolfo C , Bino G
Published: June 2011

The relation between cerebral lesions studied by computed tomography and the dementia syndrome has been evaluated in 40 patients with multi-infarct dementia, in 44 nondemented subjects with multiple infarcts, and in 30 controls matched for age and sex. Our study of the volume of ischemic lesions showed a slightly greater loss of cerebral substance in patients with multi-infarct dementia than in nondemented subjects with multiple infarcts, particularly in subjects with unilateral focal lesions and in patients with bilateral multiple cortical and subcortical lesions. The dementia syndrome was significantly associated with multiple locations of lesions in the thalamic and cortical areas supplied by the middle cerebral arteries. Moreover, patients with the dementia syndrome showed a significantly higher degree of cerebral atrophy than nondemented subjects and controls as evaluated by measurements of ventricular size, area of ventricular space, and area of subarachnoid space.
Individual variation in platelet aggregability and serum thromboxane B2 concentrations after low-dose aspirin.
Authors: Tohgi H , Tamura K , Kimura B , Kimura M , Suzuki H
Published: June 2011

The effects of low daily oral doses of aspirin (40 mg/day) on platelet aggregability and serum thromboxane B2 concentrations were studied in 19 poststroke patients. Although platelet aggregation was reduced significantly after 1 week, there was wide individual variation in the inhibition of platelet function in spite of marked decreases of serum thromboxane B2 concentrations by greater than 90% (from 224 +/- 58 to 8 +/- 8 ng/ml). There was no correlation between collagen-induced platelet aggregability and serum thromboxane B2 concentration before aspirin administration in the range 100-350 ng/ml, but after 1 week of repeated administration of aspirin, there was a correlation between platelet aggregability and serum thromboxane B2 concentrations of less than 25 ng/ml (r = 0.68, p less than 0.01). However, platelet inhibition was insufficient even in some patients with markedly decreased thromboxane B2 concentrations (less than 5 ng/ml). Our results suggest that individual variation of platelet aggregability in response to low-dose aspirin may be due to variation not only in the degree of inhibition of thromboxane A2 production but also in the relative dependence of platelet aggregation on extra-arachidonic pathways.
Regional differences in cerebrovascular cholinergic innervation in goats.
Authors: Triguero D , López de Pablo A L , Gómez B , Estrada C
Published: June 2011

The presence and distribution of a cerebrovascular cholinergic system were studied in goats. Regional cerebral blood flow was measured in the parietal cerebral cortex, caudate nucleus, and white matter by the hydrogen clearance technique in unanesthetized goats. Intravenous low doses of physostigmine, but not of neostigmine, significantly increased regional blood flow without changing mean arterial blood pressure or behavior. Increases of blood flow were greater in cerebral cortex and caudate nucleus than in white matter although the vasodilation induced by hypercapnia was similar in the three regions. Intracerebral microvessels were isolated from cerebral cortex, caudate nucleus, and white matter to evaluate choline acetyltransferase activity as a marker for perivascular cholinergic nerves. The enzyme level was higher in vessels from cerebral cortex and caudate nucleus than in vessels from white matter, which is in accordance with the functional data. These results suggest the presence of a cholinergic perivascular innervation system in intracerebral microvessels. Such innervation has a nonhomogeneous distribution throughout the brain and might be implicated in the local regulation of cerebral blood flow.
Intracarotid urokinase with thromboembolic occlusion of the middle cerebral artery.
Authors: Mori E , Tabuchi M , Yoshida T , Yamadori A
Published: June 2011

Intracarotid urokinase infusion therapy was performed on 22 patients with evolving cerebral infarction due to acute thromboembolic occlusion of the middle cerebral artery. Mean time from onset of symptoms to start of infusion and mean dosage of urokinase were 4.5 hours and 927,000 units, respectively. Immediate recanalization was achieved in 10 patients (45%) after urokinase therapy. In patients with successful recanalization, rapid amelioration of symptoms followed the restoration of blood flow. Thrombolytic recanalization was associated with reduction of neurologic deficits and of computed tomography-demonstrable infarction volume. The reduction of infarction volume and functional outcome correlated highly with the degree of reflow. Hemorrhagic transformation of infarction occurred in four patients and controllable extracranial bleeding in three patients. These results support the safety and efficacy of urokinase therapy for acute thromboembolic occlusion of the middle cerebral artery.
Treatment of sagittal sinus thrombosis associated with cerebral hemorrhage and intracranial hypertension.
Authors: Hanley D F , Feldman E , Borel C O , Rosenbaum A E , Goldberg A L
Published: June 2011

Two cases of complete sagittal sinus occlusion with multiple brain hemorrhages, elevated intracranial pressure, and disseminated intravascular coagulation are described. These patients were successfully managed using pentobarbital-induced coma to ameliorate intracranial pressure elevation. This therapy was combined with monitoring of intracranial pressure and intermittent drainage of cerebrospinal fluid to further control intracranial pressure elevations. Thrombus and coagulopathy resolved with pentobarbital alone in one patient and after pentobarbital plus heparin therapy in the second patient. It is suggested that cases of severe distal sagittal sinus thrombosis with brain hemorrhage and intracranial hypertension may benefit from combined pentobarbital coma and intraventricular drainage. This allows for stabilization of bleeding tendencies before instituting heparin therapy when necessary. Management of sagittal sinus thrombosis with barbiturates or ventricular drainage is best performed in an intensive care unit environment with continuous monitoring of intracranial pressure and substantial electrophysiologic and neuroradiologic support.
Acute stroke therapy trials: problems in patient accrual.
Authors: LaRue L J , Alter M , Traven N D , Sterman A B , Sobel E , Kleiner J
Published: June 2011

Temple University Hospital participated in a multicenter acute stroke trial but enrolled only one patient out of 192 screened over 2 years; other centers had similar difficulty in patient recruitment. We analyzed our screening data to determine which enrollment criteria created difficulties in recruitment and whether the problem was attributable to any single criterion or to combinations of criteria. Six individual criteria were frequent causes for exclusion; however, greater than 80% of the patients were excluded for multiple reasons. Consequently, modifying or eliminating any single criterion did not appreciably increase patient accrual. Only 17 of 210 possible pairs of criteria occurred with statistically significant frequency (p less than 0.05), and these were most likely random associations. Therefore, only by minimizing the number and stringency of enrollment criteria will patient accrual be at a level that allows the study to be completed in a timely manner with a fiscally reasonable number of centers.
Osteoporosis in Hemiplegia
Authors: PANIN NICHOLAS , GORDAY W. J. , PAUL B. J.
Published: June 2011

Localized osteoporosis in 25 long-term stroke patients was evaluated by means of measuring the combined cortical thickness in the humerus, radius and third metacarpal bones of both involved and noninvolved upper extremities. The combined cortical thickness was found to be consistently smaller on the involved side. Since the factors of weight bearing and calcium homeostasis were eliminated or controlled in this study, the authors were able to focus on the role of muscle pull as manifested by voluntary muscle function and spasticity in relation to the degree of cortical thinning. A smaller degree of cortical thinning was associated with better voluntary muscle function, but the relationship of spasticity to preservation of cortical thickness was not clear cut. The applicability of these techniques to the study of factors affecting localized osteoporosis is discussed.