bluuebunny/crossref_metadata_2025 huggingface dataset:
Transient embolic aorto-arteritis. Presentation of a patient.
Authors: Guerra R R , Hernandez-Batres F
Published: June 2011

The clinical and postmortem data from a 14-year-old girl who had transient embolic aorto-arteritis are presented. This disease was first described in 1974 by Peiris and Wickremasinghe in Hindu patients and is characterized by repetitive embolic occlusion of intra- and extracranial vessels of the brain, originating from focal thrombotic lesions in the aorta and its primary branches. The main histopathological lesion is located in the elastic tissue of the media in these arteries with alterations that vary from mild arteritis of the vasa vasorum to degeneration and destruction of the media which predisposes to aneurysm formation. This new entity apparently affects only adolescents and young adults and has no relation to atherosclerosis or other non-specific arteritides previously described. To our knowledge, this is the first such patient reported in America.
Changes in local cerebral blood flow following bilateral carotid occlusion in spontaneously hypertensive and normotensive rats.
Authors: Fujishima M , Ishitsuka T , Nakatomi Y , Tamaki K , Omae T
Published: June 2011

Local blood flow in the cortex and thalamus was measured by the hydrogen clearance method in spontaneously hypertensive rats (SHR) and normotensive rats (NTR) before and after bilateral carotid occlusion. There were no differences in the resting blood flow values between SHR and NTR. Following carotid occlusion cortical blood flow in SHR was markedly reduced to 17% of the resting level at 1 h and, further, to less than 10% at 3--5 h period, while in NTR it decreased only to 36--38% during 5 h occlusion. Thalamic blood flow in SHR was decreased to 39% at 1 hr and to below 20% at 3--5 h, while in NTR it remained approximately 40% of the resting level during 5 h occlusion. The blood flow reduction in either cortex or thalamus after carotid occlusion was much greater in SHR than in NTR. This difference was highly significant. The increased cerebral vascular resistance caused by persistent hypertension may play an important role in a greater reduction of blood flow in SHR after carotid occlusion. Relation of the blood flow reduction to the brain metabolism is discussed.
Reversible angiography.
Authors: Alpert J N , Gerson L P , Hall R J , Hallman G L
Published: June 2011

A 26 year old woman presented with a subacute onset of headache, hypertension, and neurologic impairment. Angiography revealed severe extracranial carotid and vertebral artery disease. Long segmental stenoses, lumen irregularities, and aneurysmal dilatations were noted. She improved with medical management and was followed for one year. Because recurrent neurologic symptoms developed, angiography was repeated and disclosed normal vasculature. "Spontaneous dissections" with recovery are the most probable explanation for this phenomenon.
Outcome of 314 patients with transient ischemic attacks.
Authors: Muuronen A , Kaste M
Published: June 2011

Between 1967 and 1976, 314 patients with transient ischemic attack (TIA) were evaluated and treated. Follow-up has been from 2.8 to 13.2 years (mean 7.8). As of 1979, 55 of the patients had succumbed to cardiovascular disease (28), cerebrovascular disease (9), malignancy (10), and other causes (8). During the follow-up period, 15 patients suffered brain infarction (4.8% under the risk) while 40 had myocardial infarction (12.7%) under the risk). Brain infarction occurred as often in patients with carotid TIA as in those with vertebral-basilar TIA, and was more common in patients under anticoagulation therapy than in those without it (p less than 0.05). Arterial hypertension, heart disease, peripheral arterial disease and diabetes did not increase the risk of brain infarction, but all (except diabetes) increased the risk of myocardial infarction. Combination of TIA with arterial hypertension, heat disease, or peripheral arterial disease increased the mortality (p less than 0.001). A life table analysis of surviving 1, 5, and 10 years gave probabilities of 99 and 100%, 89 and 91%, and 60 and 75% for males and females respectively. In the case of normotensive and hypertensive patients, a life table analysis of chances of surviving 1, 5, and 10 years gave probabilities of 100 and 95%. 94 and 80%, and 76 and 49% in both groups respectively. The result clearly emphasize treating of arterial hypertension, and demonstrate that TIA is not only a warning sign of impending stroke but also that of myocardial infarction.
Fibromuscular dysplasia and the brain. I. Observations on angiographic, clinical and genetic characteristics.
Authors: Mettinger K L , Ericson K
Published: June 2011

The angiographic, clinical, and genetic characteristics of fibromuscular dysplasia (FMD) are reviewed in 37 patients (mean age 48 years) selected from a pool of 4000 angiograms of carotid or vertebral arteries. FMD was a neglected pathogenic factor in 28 patients with hemorrhagic or ischemic cerebral lesions. The aneurysms found in 19 patients had conventional appearance and were mainly located in the internal carotid or middle cerebral arteries and on the same side as the most affected cervical artery, which suggests that aneurysms and FMD are pathogenically related. A clinical syndrome is presented where headache, ECG-abnormalities, hypertension, mental distress, tinnitus, vertigo, arrhythmia, TIA, and syncope are frequent components. Hemicrania, sometimes combined with ipsilateral Horner's Syndrome, was found in patients with advanced lesions in the carotid artery of the same side. An associated occurrence of stroke in pedigrees, especially among young and middle aged females, indicates that FMD in the majority of cases in inherited as an autosomal dominant trait with reduced penetrance in males.
Cortical injury without ischemia produced by topical monoamines.
Authors: Stein S C , Cracco R Q
Published: June 2011

Responses to monoamines perfused over the cortical surface through modified pial windows were monitored in 106 cats. Norepinephrine (NE) and serotonin (5-HT) were diluted in mock CSF to concentrations of 50 and 500 ng/ml respectively, levels at or near the maximum concentrations to which the cortical surface might be exposed in subarachnoid hemorrhage or damage to nearby neurons. Each cat had simultaneous one-hour perfusions of monoamine solution over one hemisphere and a control solution over the other hemisphere thus serving as its own control. The perfusion solutions were observed to be restricted to the area of the pial window, and minimal histological damage was seen with the perfusion technique. The 5-HT perfusions were associated with an almost 20% narrowing of small pial arteries and arterioles but no significant effect on regional cerebral blood flow (rCBF), cortical water content or cortical function as monitored by EEG and somatosensory evoked potentials (SEP). In contrast, NE caused cortical edema and changes in the EEG and SEP's without significant vascular effect. These results suggest a non-ischemic toxicity of NE released by subarachnoid hemorrhage or cerebral damage.
A randomized trial of aspirin and sulfinpyrazone in patients with TIA.
Authors: Candelise L , Landi G , Perrone P , Bracchi M , Brambilla G
Published: June 2011

In a double-blind multicenter study, 124 patients with transient ischemic attacks were randomly allocated to one of two groups treated with aspirin (ASA) or sulfinpyrazone respectively. Patients were followed up to assess the relative efficacy of the two treatments in the prevention of the outcomes of stroke, myocardial infarction, vascular death, and worsening or no improvement of TIAs. No significant difference was observed between the two treatments at the end of the follow-up period. Statistical analysis revealed a significant interaction of sex, treatment, and occurrence of events. Analysis of the results according to sex showed that male patients treated with ASA had a highly significant benefit (p less than 0.001) with a 53% risk reduction for further events. In female patients, sulfinpyrazone showed a favorable trend which was not statistically significant.
The association of cerebral aneurysms, infundibula, and intracranial arteriovenous malformations.
Authors: Miyasaka K , Wolpert S M , Prager R J
Published: June 2011

Intracranial arteriovenous malformations (AVMs) are congenital communications between the cerebral arteries and veins without an intervening capillary network. The association of the malformations with other vascular lesions such as intracranial aneurysms has previously been reported. We have reviewed 132 consecutive patients with intracranial AVMs evaluated angiographically at New England Medical Center. In addition to the expected high incidence of saccular aneurysms, a high incidence of arterial infundibula was found. A review of the association between the AVMs, aneurysms and infundibula, and possible etiologic factors in the relationship forms the subject of this report.
Cerebral blood flow studies in man using recirculation corrected height/area (H/A) computations for intravenous injection of 133Xenon.
Authors: Namon R , Reinmuth O M , Schwelm R
Published: June 2011

Our height/area (recirculation-corrected) non-invasive cerebral blood flow method compares well with k1 values and k average as determined from k1, k2, p1 and p2 by Obrist computations. The height/area method provides regional flow measurements with less variability than k1 due to low regional head counts, head motion and end-tidal gas sample variations. Derivation of the mathematical model is for a single flow compartment and suited for tomographic measurements such as PET. Collimated detector data using our computation provides a good approximation of flow even for multiple compartments. Our approach permits a lower counting rate by either a smaller isotope dose or better detector collimation than multicompartment curve fitting methods.
Nitroglycerin induced hypotension will maintain CBF in hypertensive rats.
Authors: Hoffman W E , Albrecht R F , Miletich D J
Published: June 2011

Cerebrovascular effects of intravenous (iv) nitroglycerin (NTG) infusions were tested in four month old spontaneously hypertensive rats (SHR) and Wistar Kyoto controls (WKY). Cerebral blood flow (CBF) changes were measured during iv NTG infusion in ventilated, halothane anesthetized rats using radioactive microspheres. In control WKY rats given isotonic saline infusions instead of NTG, blood pressure and CBF did not change over 3 microsphere injections. When blood pressure was decreased to 65 and then 45 torr with iv NTG infusions, CBF was maintained or increased in both SHR and WKY. There was no difference in response between SHR and WKY. These results support other reports that NTG has direct cerebrovasodilating effects, and indicate that this action will maintain adequate CBF in hypertensive as well as normotensive subjects to pressures below 50 torr.
Middle cerebral artery occlusion with migraine.
Authors: Castaldo J E , Anderson M , Reeves A G
Published: June 2011

A seven-year-old boy with migraine and a family history of hemiplegic migraine is described who, during an exacerbation, developed dysphasia and right hemiparesis. A CT scan showed a hypodense left cerebral lesion. Angiography revealed occlusion of the left middle cerebral artery at its origin. This represents the youngest case of stroke with migraine and, to our knowledge, is the first case report of angiogram-documented middle cerebral occlusion associated with migraine.
An evaluation of risk factors for stroke in a Dutch community.
Authors: Herman B , Leyten A C , van Luijk J H , Frenken C W , Op de Coul A A , Schulte B P
Published: June 2011

The objective of the present epidemiological study was to reevaluate the relationship of various suspect risk factors to stroke within a Dutch community. The Tilburg study lends support to findings in other countries concerning the greater stroke risk of persons with high blood pressure, heart disorders, and diabetes mellitus. Significant interactions of both age and a history of myocardial infarction with hypertension on stroke risk were noted. The presence of overweight and possible transient ischemic attacks (TIA) were found related to stroke onset. No increase in stroke risk was associated with cigarette smoking. The extent of leisure time physical activity during one's lifetime was found inversely related to one's chances for stroke.
Cerebrovascular arteriopathy (arteriosclerosis) and ischemic childhood stroke.
Authors: Daniels S R , Bates S , Lukin R R , Benton C , Third J , Glueck C J
Published: June 2011

The aim of this report is to describe the intracranial cerebrovascular abnormalities and clinical status of 8 children who had familial lipoprotein disorders and evidence of thromboembolic cerebrovascular disease. Six of the 8 children had low levels of plasma high density lipoprotein cholesterol, two had high triglyceride levels, and all came from kindreds characterized by familial lipoprotein abnormalities and premature cardio- and/or cerebrovascular atherosclerosis. Vascular occlusion, irregularities of the arterial lumen, beading, tortuosity, and evidence of collateralization were consistently noted. We speculate that cerebrovascular arteriosclerosis in pediatric ischemic stroke victims who have familial lipoprotein abnormalities may be related to lipoprotein-mediated endothelial damage and thrombosis formation, or to the failure to restore endothelial cells' integrity following damage. The apparent association of lipoproteins and strokes in children and their families merits further exploration, particularly when assessing cerebral angiograms in pediatric ischemic stroke victims. In children with unexplained ischemic cerebrovascular accidents, the diagnostic possibility of occlusive arteriosclerosis with thrombosis must be entertained.
Cerebral edema following experimental subarachnoid hemorrhage.
Authors: Shigeno T , Fritschka E , Brock M , Schramm J , Shigeno S , Cervoś-Navarro J
Published: June 2011

The development of cerebral edema after experimental subarachnoid hemorrhage (SAH) was studied in cats by determining regional brain tissue water content with the microgravimetric technique as well as the drying-weighing method. SAH was induced by withdrawing needles previously pierced into one or both infraclinoid internal carotid arteries through a unilateral transorbital approach. Serial determinations of regional cerebral blood flow (rCBF) by labelled microspheres, and monitorings of vital signs such as intracranial pressure (ICP), blood pressure and EEG were carried out up to 24 h after SAH. Animals could be classified into three grades according to the severity of SAH. In grade I, the increase of ICP was transient and minor. In grade II, ICP increased up to 200 mm Hg with a marked reduction of rCBF below 20% of control in cerebral hemispheres. Following subsequent reduction of ICP, rCBF increased over control, indicating reactive hyperemia. Thereafter, a great reduction of rCBF was again observed. In grade III, rCBF was sustained at essentially zero flow with the presence of continuously increased ICP above 100 mm Hg. Cerebral edema was observed particularly in the parasagittal water-shed areas of all grade II animals. It is concluded that cerebral edema complicating SAH is caused by the combination of an initially induced global cerebral ischemia and the subsequent recovery of cerebral circulation. Post SAH hypertension is another factor to exacerbate the development of cerebral edema.
Intravenous digital subtraction angiography: an index of collateral cerebral blood flow in internal carotid artery occlusion.
Authors: Awad I , Little J R , Modic M T , Furlan A J
Published: June 2011

The objective of this investigation was to correlate Xenon-133 inhalation rCBF measurements with the pattern of cortical arterial filling on intravenous DSA in 18 patients with unilateral internal carotid artery occlusion. Of 9 patients showing symmetrical filling of hemispheric cortical arteries, none showed an inter-hemispheric difference in rCBF ( delta Fg) greater than 10ml/100gm/min. Of 9 patients showing delayed cortical opacification ipsilateral to the internal artery occlusion, 3 showed a delta Fg greater than 10ml/100gm/min, 3 showed a delta Fg in the 7-10ml/100gm/min range, and 3 had a delta Fg less than 7ml/100gm/min. All patients with asymmetric abnormalities in the rCBF profile had the delayed pattern of cortical filling on DSA. The presence of symmetrical hemispheric opacification of cortical arteries on DSA indicates adequate interhemispheric redistribution of rCBF and patent inter-hemispheric collateral channels, but not necessarily normal cerebral blood flow. The presence of delayed cortical arterial opacification on the side of internal carotid artery occlusion does not necessarily imply significant inter-hemispheric rCBF differences, nor does it rule out a normal rCBF. The presence of bilateral reduction of rCBF and symmetrical cortical artery filling on DSA may represent an "interhemispheric steal".
Effects of hyperventilation on cerebral blood flow and brain tissue metabolism in normotensive and spontaneously hypertensive rats.
Authors: Ishitsuka T , Fujishima M , Nakatomi Y , Tamaki K , Omae T
Published: June 2011

Cerebral vascular carbon dioxide (CO2) reactivities were compared in normotensive (NTR) and hypertensive (SHR) rats. Cerebral blood flow (CBF) in cortex and thalamus were evaluated before and during one hour of hyperventilation. After one hour of hyperventilation brain lactate, pyruvate, and ATP concentrations were also determined. Significant and similar reductions of CBF due to hyperventilation induce hypocapnia were found in both NTR and SHR groups. In contrast the percent increase in cerebrovascular resistance (CVR) per unit decrease in paCO2 was significant, indicating that hypocapnia induced vasoconstriction is greater in NTR than in SHR groups. During hyperventilation the average value for lactate in the NTR group was 3.98 mM/kg. In contrast it was 3.15 mM/kg in the SHR group, a significant difference (p less than 0.05). When paCO2 fell below 15 mm Hg the cerebral lactate increased strikingly in the NTR group and cortical CVR was reduced suggesting that an accumulation of the ischemic metabolites caused dilatation of the constricted cerebral vessels. In contrast the SHR group disclosed no such changes. The increase CVR characteristic of SHR appeared to diminish the cerebral vasoconstrictive response to hypocapnia. As a result ischemic metabolites in the brain do not increase in this group to the degree that they do in NTR.
The influence of antihypertensive therapy on cerebral autoregulation in aged hypertensive rats.
Authors: Hoffman W E , Miletich D J , Albrecht R F
Published: June 2011

Cerebrovascular responses to hemorrhage induced hypotension were tested in aged (24 month) spontaneously hypertensive rats (SHR) and normotensive Wistar Kyoto (WKY) after ten weeks of antihypertensive drug or sham treatment. Antihypertensive drug treatment consisted of 1 mg/kg/day minoxidil, 4 mg/kg/day hydralazine and 4 mg/kg/day propranolol given in the drinking water. Antihypertensive therapy produced a 30% decrease in systolic blood pressure in aged SHR to levels not significantly different from sham treated WKY. Cerebral blood flow (CBF), measured under control conditions using ketamine anesthesia, was not significantly different between sham and drug treated SHR and WKY. Cerebral oxygen metabolic rate (CMRO2) was significantly decreased in drug treated SHR and WKY compared to sham treated rats. Lowering blood pressure to a level between 80 and 95 torr produced no significant change in CBF or CMRO2 in sham or drug treated WKY or antihypertensive treated SHR, but a produced a significant decrease it both CBF and CMRO2 in sham treated SHR. Decreasing mean blood pressure to 50-60 torr produced a significant decrease in CBF but not CMRO2 in both WKY treatment groups and in hypertensive treated SHR, but again in sham treated SHR both CBF ana CMRO2 were significantly decreased. These results indicate that aged hypertensive rats are unable to maintain CBF or CMRO2 under even moderate hypotensive test conditions, and that cerebral autoregulation can be improved with antihypertensive therapy.
Evaluation of brainstem stroke using brainstem auditory evoked responses.
Authors: Stern B J , Krumholz A , Weiss H D , Goldstein P , Harris K C
Published: June 2011

Brainstem stroke syndromes are primarily determined by clinical criteria. There are few diagnostic procedures which are of benefit for the evaluation of brainstem ischemic events. Brainstem auditory evoked responses (BAERs) are a new electrophysiologic technique for assessing brainstem function. To evaluate the use of BAERs in patients with brainstem ischemic events, 35 individuals with recent brainstem strokes, selected by strict clinical criteria, were evaluated with BAERs. The initial BAER was abnormal in 22 of 35 patients (63%). When the clinical course and site of the lesion are correlated with the BAER results, several trends emerge. An unstable course, characterized by progression or remission and relapse, was present in 19/35 (54%) of patients, and 15/19 (79%) of these individuals had an initially abnormal BAER. The other 16 brainstem stroke patients with a stable clinical course had an initially abnormal BAER in 7 instances (44%). This difference is statistically significant at the p = 0.04 level. The principal sites of ischemia were mesencephalic in 11/35, pontine in 13/35, and medullary in 11/35. The association of an abnormal BAER with an unstable clinical course seemed independent of the site of the lesion, However, of the 9 deaths that occurred, all were in patients with mesencephalic or pontine lesions, and 8 of these individuals had an initially abnormal BAER. Abnormal BAERs in patients with brainstem ischemic lesions correlate with an unstable clinical course. Furthermore, individuals with pontomesencephalic infarction and abnormal BAERs have an especially poor prognosis. The BAER may be of prognostic value in the early evaluation of patients with brainstem ischemic strokes.
Fusiform basilar aneurysm as a cause of embolic stroke.
Authors: Steel J G , Thomas H A , Strollo P J
Published: June 2011

Giant fusiform basilar aneurysms (dolicho-ectatic basilar anomalies) are rare and have not previously been reported to cause embolic infarction in territory distal to the aneurysm. They most commonly present as posterior fossa mass lesions with brainstem compression and cranial neuropathies. Originally considered atherosclerotic in etiology, recent authors feel that they may represent a unique arteriopathy characterized by loss of elastin in the vessel wall. We report a case which presented solely as an occipital lobe infarction. To our knowledge, this is the first case in which a fusiform basilar aneurysm presented with an embolic infarction as its only manifestation.
Experimental air embolism of the brain: an analysis of the technique in the rat.
Authors: Furlow T W
Published: June 2011

Air embolization of the brain produces cerebral ischemia that can be focal and reversible. The method has previously been hampered by (1) lack of selective arterial injection of the embolus, (2) disruption of local hemodynamic relationships by ligation of major arterial channels, (3) excessive volume of the air embolus, and (4) uncontrolled bubble size. To minimize these factors, a technique was devised in the rat whereby a fine catheter was advanced through a branch of the external carotid artery into the internal carotid artery. Air emboli of 5 microliters were found to arrest blood flow and to attenuate electrical activity in the ipsilateral cerebral hemisphere for seconds to a couple of minutes. The duration of ischemia varied from region to region, and it tended to be prolonged by arterial hypotension. In the nonembolized hemisphere, CBF never declined abruptly (indicating no cross-over of air) although electrical activity was suppressed in two-thirds of the animals.
Acetylsalicylic acid in the prevention of stroke in patients with reversible cerebral ischemic attacks. A Danish cooperative study.
Authors: Sorensen P S , Pedersen H , Marquardsen J , Petersson H , Heltberg A , Simonsen N , Munck O , Andersen L A
Published: June 2011

Two hundred and three patients, 148 males and 55 females, who during the last month before admission had experienced at least one reversible cerebral ischemic attack of less than 72 hours duration, were randomly assigned to treatment with either acetylsalicylic acid (ASA) 1000 mg daily (101 patients) or placebo (102 patients). The average follow-up period was 25 months. The two treatment groups were comparable with respect to age, sex, associated diseases, risk factors, number and duration of cerebral ischemic attacks. No statistically significant differences were found between the treatment groups as to the primary end point: stroke or death (ASA group 20.8%, placebo group 16.7%). Occurrence of transient ischemic attacks during the treatment period was not reduced by ASA treatment, whereas there was a trend suggesting fewer myocardial infarctions in the ASA group (5.9%) than in the placebo group (13.7%). The difference, however, was not statistically significant (p = 0.10). We were thus unable to demonstrate any favorable influence of ASA 1000 mg daily in patients with reversible ischemic attacks. This study does not, of course, prove that ASA treatment is ineffective in stroke prevention.
"AICLA" controlled trial of aspirin and dipyridamole in the secondary prevention of athero-thrombotic cerebral ischemia.
Authors: Bousser M G , Eschwege E , Haguenau M , Lefaucconnier J M , Thibult N , Touboul D , Touboul P J
Published: June 2011

604 Patients with atherothrombotic cerebral ischemic events (transient, 16%: or completed, 84%) referrable either to the carotid or to the vertebral-basilar circulation were entered into a double blind randomized clinical trial (AICLA) to determine whether aspirin (A) (1 g/day) or aspirin (1 g/day) + Dipyridamole (225 mg/day) (AD) would produce a significant reduction in the subsequent (3 years) occurrence of fatal and nonfatal cerebral infarction. Randomization produced remarkably comparable treatment groups and this good comparability was maintained throughout the study. Adherence to the protocol and drug compliance were excellent. Side effects, particularly symptoms of peptic ulcer and hemorrhagic events were significantly (p less than 0.03) more frequent in the two treatment groups containing aspirin. With the exception of patients who withdrew from the study, each patient was followed for 3 years. At the end of the study, the number of fatal and nonfatal cerebral infarctions was 31 in the placebo (P) group, 17 in the A group and 18 in the AD group. Taking into account the duration of follow-up for each patient, these figures correspond to cumulative rates of 18% in the P group and 10.5% in each of the 2 active treatment groups. Analysis with the Mantel Method showed: 1)--A difference at the 6% level between the 3 groups and between P and AD; 2)--A difference at the 5% level between P and A; 3)--No difference between (A and AD; 4)--A difference at the 2% level between the P group and the two treated groups taken together (A + AD). Among other diseases occurring during the trial, the only significant difference concerned myocardial infarction, which was less frequent in the 2 treated groups (P less than 0.05). Subgroup analysis failed to show a significant sex difference in the efficacy of aspirin. It is concluded that, in patients comparable to those defined in the protocol, Aspirin (1 g) has a significantly beneficial effect in the secondary prevention of atherothrombotic cerebral infarction.
Association between sympathetic nerve activity and cerebrovascular protection in young spontaneously hypertensive rats.
Authors: Mueller S M , Ertel P J
Published: June 2011

The purpose of this study was to determine resting and maximal superior cervical sympathetic nerve activity in spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) at five and ten weeks of age as hypertension was developing. Basal cervical sympathetic nerve activity (SNA) of five week SHR was 58 +/- 3 muv* which was significantly elevated over age-matched WKY (SNA = 30 +/- 4 muv, *p less than 0.001) and ten week SHR (SNA = 30 +/- 4 muv, *p less than 0.001) as well as ten week WKY (SNA = 24 +/- 4 muv, *p less than 0.001). Thus, during basal conditions five week SHR nerve traffic was approximately two times that found in age-matched WKY as well as in ten week SHR and WKY. The peak sympathetic nerve activity in response to rapid hemorrhage in five week SHR (215 +/- 16 muv*) was significantly elevated over the maximal response of WKY (140 +/- 23 muv) (*p less than 0.02). Ten week SHR also reached a maximal sympathetic nerve activity (187 +/- 28 muv*) that was significantly elevated over WKY (100 +/- 15 muv) (*p less than 0.02). Thus, both five and ten week SHR had a greater capacity for elevated nerve activity following rapid hemorrhage than age-matched WKY. The elevation in resting cervical sympathetic activity in five week SHR, and the elevated capacity for sympathetic neural response in both five as well as ten week SHR, are consistent with a central nervous system abnormality in SHR that could relate to the previously described protective influence of sympathetic nerves on SHR cerebral blood vessels as hypertension is developing.
True three-dimensional nuclear magnetic resonance neuro-imaging in ischemic stroke: correlation of NMR, X-ray CT and pathology.
Authors: Pykett I L , Buonanno F S , Brady T J , Kistler J P
Published: June 2011

True three-dimensional proton nuclear magnetic resonance (NMR) imaging was performed on an 84-year-old man following a recent cerebral embolic infarction. NMR data obtained using different pulse sequences were inter-correlated, stressing the significance of image appearance in terms of the NMR tissue parameters. Planes selected for display from the three-dimensional data set allowed optimal visualization of the pathology. Accurate correlations of the NMR data with X-ray computerized tomography scans and with subsequent autopsy findings indicate that NMR may play an important role in the detection and diagnosis of ischemic stroke.
Acute NMR changes during MCA occlusion: a preliminary study in primates.
Authors: Spetzler R F , Zabramski J M , Kaufman B , Yeung H N
Published: June 2011

Advancements in computer science and magnet design have resulted in the recent development of high resolution NMR imaging systems. Using our primate model we evaluated the ability of NMR scanning to detect early changes following middle cerebral artery (MCA) occlusion. Serial NMR scans documented progressive changes secondary to edema and swelling beginning ninety minutes after MCA occlusion. NMR was also able to readily demonstrate the area of cerebral infarct 10 days after a six hour episode of MCA occlusion. Soft tissue contrast and image resolution were superb. Correlation with pathologic sections was excellent.
Chronological sequences and blood-brain barrier permeability changes in local injury as assessed by nuclear magnetic resonance (NMR) images from sliced rat brain.
Authors: Asato R , Handa H , Hashi T , Hatta J , Komoike M , Yazaki T
Published: June 2011

Two experiments were done with a prototype mini-NMR imager to evaluate the potential application of nuclear magnetic resonance (NMR) imaging in neuropathology. Cryo-injury-induced brain edema in brain slices from 22 adult male rats was imaged for observing the chronological sequences. Blood-brain barrier permeability changes were evaluated in 12 other brain slice images. EDTA-2Na-Mn solution was intravenously injected as an indicator of blood-brain barrier permeability. Contrast enhancement was achieved by changing the NMR imaging parameters. High resolution imaging permitted visualization of the corpus callosum, the thickness of which was only 0.2-0.4 mm. The extent of edema in gray matter was clearly shown with a striking contrast; no consistent findings were seen with slight differences in water content between edema and the surrounding normal cortex. As a result, the chronological sequences of brain edema were clearly observed. Mn-EDTA leaking from the circulating blood through the damaged capillary wall had a "paradoxical enhancement" effect on the NMR images; this effect might be suitable for evaluating blood-brain barrier permeability changes in NMR images.
Measurement of carotid blood flow in man and its clinical application.
Authors: Uematsu S , Yang A , Preziosi T J , Kouba R , Toung T J
Published: June 2011

With the use of a new ultrasonic volume flow meter (VFM), over 8000 measurements of common carotid blood flow were made in 120 normal control subjects and 550 patients with various neurological disease. The accuracy of the flow meter in measuring blood flow on an experimental model ranged from 93 to 97%. In normal subjects, common carotid blood flow varies with age. It increased from newborn to age 20 and gradually decreased thereafter. In normal healthy subjects, the flow varies within +/- 6.7% (2SD) at one sitting (intrasession) and +/- 21.2% (2SD) from week to week (intersession study). Carotid blood flow varies linearly with PaCO2 and increased markedly in response to endotracheal intubation. In healthy adults, the flow ratio between the two common carotid arteries is 1.07 +/- 0.052. This ratio increases in patients with transient ischemic attacks to 1.28 +/- 0.23 (p less than 0.05) and in patients with intracranial space occupying lesions to 1.46 +/- 0.39, (p less than 0.01). In 26 consecutive cases of carotid endarterectomies, the preoperative common carotid blood volume flow was 5.1 +/- 1.0 cc/sec. All cases preoperatively had at least 30% stenosis and ranged from 30 to 100% stenosis. The carotid blood volume was significantly increased post-operatively (p less than 0.001). The overall accuracy in detecting carotid and cerebral arterial disease is 89% with sensitivity of 96% and the specificity of 71%. Our clinical experience indicates that this device is not only a valuable noninvasive diagnostic tool for evaluation of carotid disease but also appears to be useful in assessing cerebral blood flow.
CSF enzymes in lacunar and cortical stroke.
Authors: Donnan G A , Zapf P , Doyle A E , Bladin P F
Published: June 2011

Cerebrospinal fluid enzyme levels of creatine kinase (CK), lactate dehydrogenase (LDH), glutamate oxaloacetate transaminase (GOT) and angiotensin converting enzyme (ACE) were studied in 40 acute stroke patients comprising 20 lacunar strokes and 20 cortical strokes. A marked elevation of at least one of the enzymes CK, GOT or LDH was seen in 80% of cases of cortical strokes. No elevation was seen in lacunar stroke with CK, GOT or ACE and only a slight elevation with LDH. Within the cortical group, there was a correlation between the site, size of infarction seen on CT scan and enzyme level. These findings may help to explain the previously noted unpredictability of rises in CSF enzymes in stroke patients. In certain instances, a study of CSF enzymes may be of use to distinguish cortical from lacunar stroke. A precise diagnosis of lacunar infarction is important for management purposes, entry into stroke treatment trials or description of new syndrome types.
Acute hypertensive subdural hematoma from arterial rupture shortly after the onset of cerebral subcortical hemorrhage: leakage of contrast medium during angiography.
Authors: Arai H
Published: June 2011

A case is reported of a Japanese female in whom acute right subdural hematoma due to the spontaneous rupture of the posterior branch of the right central artery occurred shortly after the onset of hypertensive subcortical hemorrhage of the right occipital lobe. Marked hypertension persisted. There was no evidence of subdural hematoma when a small collection of extravasated contrast medium from the cortical artery was revealed during right carotid angiography. Soon thereafter the patient became comatose and developed decerebrate posturing. Computed tomography scan was done immediately and a large subdural hematoma was identified. There was a gratifying response to prompt recognition and neurosurgical therapy of the condition. The pinpoint rupture of the cortical artery is considered to have occurred during marked hypertension. Previous 39 cases with subdural hematomas from arterial rupture, 27 traumatic and 12 spontaneous nontraumatic, are reviewed.
Subarachnoid hemorrhage in New Zealand: an epidemiological study.
Authors: Bonita R , Beaglehole R , North J D
Published: June 2011

To examine long-term trends in subarachnoid hemorrhage (SAH) mortality and morbidity, an analysis of routinely available information is presented for the 20 year period from 1959. To document the current incidence and case fatality of SAH, the results of a large scale community-based study in the Auckland region are presented. SAH mortality rates for both men and women, especially women, have declined since the mid-1970's. The decline appears to be real, and is most striking in the 45-64 year age groups. A corresponding decline in discharge rates from hospital has also occurred in these age groups. In contrast, cases fatality rates have remained stable at about 42% for the 20 year period under review. The community-based study identified 92 cases in a total population of 829,464 in a twelve month period. The age standardised incidence rates were 13.4 and 15.8 per 100,000 for men and women respectively. In the age group 25-35 years, the incidence rate was particularly high at 8.5/100,000. Case fatality at 28 days was 52%. A decline in incidence appears the most likely explanation for the overall decline in national mortality.
Cerebral artery mass in the rabbit is reduced by chronic sympathetic denervation.
Authors: Bevan R D , Tsuru H , Bevan J A
Published: June 2011

Weights of matching right and left middle or posterior cerebral arteries and their main branches from the same animal were compared 8-10 weeks after unilateral denervation by superior cervical ganglionectomy. When compared in pairs, the denervated arterial systems weighed significantly less (mean 85%) than their innervated counterparts. This suggests that the sympathetic innervation exerts a trophic influence on extracerebral arteries.
Unusual clinical signs in left subclavian artery occlusion: clinical and angiographic correlation.
Authors: Goldenberg E , Arlazoroff A , Pajewski M , Carpel C L
Published: June 2011

A case of left subclavian steal syndrome with transient ischemic attacks of left carotid artery distribution is presented. An attempt to explain this uncommon symptomatology is based on a rare patent cervical arterial network, stealing blood from the left common carotid artery and supplying the distal portion of the obstructed left subclavian artery.
Spontaneous brain hemorrhage.
Authors: Ojemann R G , Heros R C
Published: June 2011

Spontaneous brain hemorrhage accounts for about 10% of all strokes and is fatal in about 50% of the cases. Its incidence, in contrast to other types of strokes, has not declined. Hypertension accounts for about half of these hemorrhages; the rest are due to tumors, aneurysms and vascular malformations, inflammatory and degenerative vasculopathies and hematologic and iatrogenic disorders of coagulation. In some patients no cause is ever found. Hypertensive brain hemorrhage occurs in the deep gray nuclei of the hemispheres, the cerebellum, and the pons and results in specific clinical syndromes depending on the location. Computerized tomography has revolutionized the diagnosis of brain hemorrhage and is resulting in the development of rational criteria for medical and surgical management of these lesions. Intensive medical therapy guided by clinical status and continuous monitoring of ICP may improve outcome. Surgical removal of the hematoma is indicated in lobar and putaminal hemorrhages when the patient is deteriorating in spite of vigorous medical therapy. In addition most large (greater than 3 cm) cerebellar hemorrhages, as well as smaller cerebellar hemorrhages that result in significant brain stem compression should be evaluated. The roles of intensive medical therapy, elective late surgery and of immediate operation in improving eventual functional outcome need to be investigated further.
Factors affecting the prognosis in thalamic hemorrhage.
Authors: Kwak R , Kadoya S , Suzuki T
Published: June 2011

The present study deals with the factors affecting the prognosis in the acute stage of 29 cases with hypertensive thalamic hemorrhage diagnosed by CT scan. It was thought that the following factors were significantly related to the outcome of the patients who were unable to lead daily life, remained in vegetative state or died: (1) consciousness level was below 10 in the so-called 3-3-9 formula, (2) bilateral Babinski's signs were observed, (3) localization of the hematoma was all the thalamic nuclei type, (4) hematoma volume was above 10 ml, (5) the maximum dimension of hematoma was over 30 or 35 mm, maximum width over 30 mm, maximum length over 25 mm and maximum height over 30 or 40 mm, and (6) the ventricles were dilatated. The prognosis had no significant relationship with the age of the patients, the side of the hematoma, the presence or the absence of ventricular penetration of the hematoma, or the existence of midline shift. We believe that in the acute stage of hypertensive thalamic hemorrhage, the prognosis can be forecasted by neurological findings, accurate calculation of the hematoma volume and size, localization of the hematoma and presence or absence of ventricular dilatation as determined by CT scan.
Differential outcome to middle cerebral artery occlusion in spontaneously hypertensive stroke-prone rats (SHRSP) and Wistar Kyoto (WKY) rats.
Authors: Coyle P , Jokelainen P T
Published: June 2011

Evidence was found for different outcomes to middle cerebral artery occlusion in the young genetically hypertensive stroke-prone rat (SHRSP) compared to sham operated controls and the Wistar Kyoto rat (WKY). Qualitatively and quantitatively different gross lesions marked by Evans blue-albumin, cortical atrophy, large areas of strikingly altered cortical histology, postoperative survival and motor behavioral deficits differentiate young SHRSP from sham operated controls and the normotensive WKY. We conclude that the limited focal lesion observed in normotensive and sham operated rats is primarily due to surgical trauma of exposing the vessel and passing the ligature deep to it. The grossly larger and qualitatively different lesion in the SHRSP is the result of an inadequate circulation provided by the dorsal cerebral arterial collaterals. Since the 5-6 week old SHRSP were only mildly hypertensive (systolic blood pressure 140 mm Hg), the inadequate collateral circulation appears to be related to either a genetic or acquired problem rather than being secondary to a vascular lesion of chronic hypertension.
Delayed cerebellar infarction following a car accident.
Authors: Nichelli P , Gibertoni M , Guerzoni C
Published: June 2011

A patient developed a cerebellar infarction five weeks after a car accident. The pathophysiology and the medico-legal implications are discussed.
Pial arterial pressure in cats following middle cerebral artery occlusion. 1. Relationship to blood flow, regulation of blood flow and electrophysiological function.
Authors: Shima T , Hossmann K A , Date H
Published: June 2011

In lightly anesthetized cats, the left middle cerebral artery was occluded using a transorbital approach. Pial arterial pressure was measured with a feedback-controlled micropressure recording system in the territory of the occluded artery, and compared with changes of cortical blood flow, cortical steady potential and cortical EEG activity. After middle cerebral artery occlusion pial artery pressure fell from 56.2 +/- 1.6 to 7.8 +/- 0.4 mm Hg; during the following two hours it again slowly rose to about 15 mm Hg. Cortical heat conductance, as a measure of blood flow, decreased from 15.1 +/- 0.2 to 11.9 +/- 0.2 X 10(-4) cal X cm-1 X sec-1 X degrees C-1, and remained at this level throughout the observation period. Cortical steady potential shifted by 9.1 +/- 0.7 mV towards negativity, and EEG amplitude was reduced by about 50%. Pial arterial pressure correlated with blood flow, cortical steady potential and EEG amplitude, but not with EEG frequency. Autoregulation and CO2 reactivity of blood flow were disturbed after middle cerebral artery occlusion. Calculation of extra- and intracortical vascular resistances revealed that this disturbance was entirely due to intracortical vasoparalysis whereas the collateral vessels supplying the ischemic territory continued to react to both pressure and CO2 changes. Maintained vascular reactivity of collateral vessels, therefore, is a decisive factor for the efficiency of therapeutic blood flow improvement after acute middle cerebral artery occlusion.
Cerebral vascular response to moderate blood loss: modification by hypertension.
Authors: Holladay F P , Bean J R , Young B , Todd E P , Roy M W
Published: June 2011

To study the effect of non-hypotensive hemorrhage on cerebral blood flow in normo- and hypertensive states, chloralose anesthetized cats were subjected to graded blood loss (5 ml/kg) every 30 min. Cerebral blood flow was measured using radiolabelled microspheres or H2 clearance. Hypertension was produced by infusion of phenylephrine to a diastolic blood pressure of 100 mm Hg. Control animals suffered no net blood loss. PCO2 was between 28 and 32 mm Hg for all groups over the entire experiment. In normotensive cats, cerebral blood flow increased following withdrawal of 10 ml/kg of blood. In hypertensive cats, cerebral blood flow increased after withdrawal of 20 ml/kg of blood. These findings were consistent for all brain regions examined. Animals without blood loss, whether normo- or hypertensive showed no consistent change in cerebral blood flows. Possible explanations for these findings, particularly neurally mediated responses, are discussed.
Carotid artery noninvasive testing is being overused.
Authors: Berguer R
Published: June 2011

The most frequent tests done in the evaluation of patients with potential cerebrovascular disease are Oculoplethysmography (OPG) and Imaging procedures. These procedures are useful in the evaluation of asymptomatic carotid bruits and may be helpful in evaluating patients with nonhemispheric symptoms. However, there is no reasonable indication for the use of these noninvasive procedures on patients with lateralizing hemispheric or ocular transient ischemic attacks. Lateralizing transient ischemic attacks are very often caused by ulcerated non-stenosing lesions which are easily missed by these noninvasive means. Arteriography is mandatory in this group whenever the patient is a potential surgical candidate should an appropriate lesion be found. Finally, progress made in bruit analysis is acknowledged but the clinical relevance of this datum is questioned.
Cerebrovascular diseases and their underlying vascular lesions in Hisayama, Japan--a pathological study of autopsy cases.
Authors: Masuda J , Tanaka K , Omae T , Ueda K , Sadoshima S
Published: June 2011

Frequency of cerebrovascular diseases (CVD) and their underlying vascular lesions were analyzed in 724 autopsy cases, aged 40 years and over, in the community of Hisayama, Japan during the period 1961 to 1981. Cerebral infarction (CI) was more frequently found at autopsy than cerebral hemorrhage (CH) with a ratio of infarction and hemorrhage of 4.4. Small CI occupied 75.7% of the cases with CI. The cases with any type of CVD showed more severe atherosclerosis of the major cerebral arteries than did those without CI or CH. Cerebral atherosclerosis of those with large and medium CI was the greatest, and with decreasing severity in those with small CI and with CH sequentially. Fibrinoid necrosis of the intracerebral small arteries was frequently found in cases with hypertension and particularly associated with CH. The decline in frequency of CH was confirmed; however, changes in frequency of CI were not evident. Fibrinoid necrosis was also reduced, although the severity of cerebral atherosclerosis showed no definite change. The decline of CH seemed to be ascribed to the reduction of fibrinoid necrosis of the intracerebral small arteries.