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PubMedDate not supplied

Respiratory rate and pattern disturbances in acute brain stem infarction.

Respiratory rates and patterns were studied in 23 patients with acute brain stem infarction using impedance pneumography. Autopsy was obtained in six of eight fatal cases. Pontine lesions were present in all patients, with coexistent infarction of midbrain in four and of medulla in nine. Respiratory rate and pattern abnormalities observed included Cheyne-Stokes respiration, Cheynb-Stokes variant pattern and tachypnea. Abnormalities of respiratory rate and pattern of varying duration were observed at some time in all patients. All patients in whom prominent Cheyne-Stokes respiration or tachypnea were observed had extensive bilateral pontine lesions involving both basal and tegmental portions. However, not all patients with large pontine infarcts had Cheyne-Stokes respiration or tachypnea. Cheyne-Stokes respiration was prominent in four patients (two fatal, two nonfatal). Cheyne-Stokes variant pattern was present frequently in four patients (one fatal, three nonfatal). Sustained tachypnea developed in five patients, four of whom died. In ten patients (one fatal, nine nonfatal), normal respiratory rate and pattern predominated with only rare or occasional apperance of Cheyne-Stokes respiration or Cheyne-Stokes variant pattern, especially during sleep. The types of respiratory rate and pattern abnormalities in acute brain stem infarction were not specifically related to the level of lesions, but rather to the size and bilaterality of the lesions. Respiratory alkalosis was present in varying degrees in most patients with either tachypnea or prominent CSR.

Acute Disease↗
PubMed2002

Increase of intracranial pressure after hypothermic circulatory arrest in a chronic porcine model.

OBJECTIVE: An increase in intracranial pressure has been shown to threaten the outcome of patients with ischemic or traumatic brain injury. Its impact on the outcome of pigs undergoing hypothermic circulatory arrest has been evaluated in this study. DESIGN: Fifty-six pigs underwent a 75-min period of hypothermic circulatory arrest at 20 degrees C. Intracranial pressure, cerebral microdialysis, hemodynamic and metabolic parameters were monitored throughout the experiment. The animals were allowed to survive until the 7th postoperative day and, then, electively killed. RESULTS: The 7-day survival rate was 60.7%, and among survivors, 20 of them (58.8%) developed brain infarction. A significant increase in intracranial pressure as compared with the baseline level was observed since the end of cooling (p = 0.047) and the difference became larger during all the postoperative intervals (p < 0.0001). Animals that died postoperatively tended to have higher intracranial pressure levels during all the postoperative intervals, but such a difference reached significance only at the 4-h postoperative interval (p = 0.040). The same tendency was observed among animals that survived until the 7th postoperative day and that developed brain infarction or not, but the difference between these two groups did not reach statistical significance. The animals that died or developed postoperatively brain infarction had higher intracranial pressure values postoperatively as compared with those that survived without developing brain infarction and such a difference reached significance at the 2-h (p = 0.015) and 4-h postoperative intervals (p = 0.035). The peak intracranial pressure was 17.2 mmHg (IQR, 13.7-20.8) in animals that died or developed brain infarction and 14.1 mmHg (IQR, 11.8-16.4) in those that survived 7 days without developing brain infarction (p = NS). CONCLUSION: Intracranial pressure increases significantly after 75 min of experimental hypothermic circulatory arrest and such an increase is associated with a high risk of postoperative death and brain infarction.

Animals↗
PubMed2006

Exercise pre-conditioning strengthens brain microvascular integrity in a rat stroke model.

Increasing evidence indicates that physical activity reduces brain damage after stroke. The purpose of this study was to determine whether exercise-induced neuroprotection is associated with improved brain integrity in stroke. Adult male Sprague-Dawley rats (3 months old, n=38) exercised on a treadmill, which required repetitive locomotor movement, for 30 minutes each day for 3 weeks. Then, using an intraluminal filament, stroke was induced by either 2 hours middle cerebral artery (MCA) occlusion followed by 24 or 48 hours of reperfusion. Brain damage was determined by evaluating brain infarction and brain edema, as well as ultrastructural alteration in endothelial-matrix-astrocyte interfaces.Pre-ischemic motor exercise significantly (p<0.01) reduced infarct volume in the frontoparietal cortex and the dorsolateral striatum by 79%. By comparing the percentage difference in brain volume between the right (stroke site) and left hemispheres, we demonstrated a significant (p<0.01) reduction in brain edema associated with reduced infarct volume in a 3 week exercise group (Group 1, n=10) and a 3 week exercise plus 3 week rest group (Group 2, n=10). Edema in cortex and striatum was 19 +/- 4% without exercise pre-conditioning (n=10), in contrast to 5 +/- 3% (Group 1) or 6 +/- 4% (Group 2). The thickness of the basal lamina was enhanced by exercise. In ischemic rats without pre-exercise, alterations in microvessel ultrastructure with decreased luminal area, parenchymal edema and swollen astrocyte end-feet, as well as an abnormally thin basal lamina were observed. In contrast, exercise pre-conditioning significantly reduced the ischemic alterations, decreasing brain edema and increasing basal lamina thickness. This study suggests that exercise pre-conditioning reduces brain injury by decreasing cerebral permeability and enhancing brain integrity after stroke. This exercise-induced endogenous neuroprotection could be an effective strategy to ameliorate ischemic brain injury from stroke.

Animals↗
PubMed2001

[Diffusion-weighted magnetic resonance imaging (MRI) in acute brain stem infarction].

Diffusion-weighted magnetic resonance imaging (DWI) provides one of the earliest demonstrations of ischemic lesions. However, some lesions may be missed in the acute stage due to technical limitation of DWI. We therefore conducted the study to clarify the sensitivity of DWI to acute brain stem infarctions. Twenty-eight patients with the final diagnosis of brain stem infarction(midbrain 2, pons 9, medulla oblongata 17) who had been examined by DWI within 24 hours of onset were retrospectively analyzed for how sensitively the initial DWI demonstrated the final ischemic lesion. Only obvious(distinguishable with DWI alone without referring clinical symptoms and other informations) hyperintensity on DWI was regarded to show an ischemic lesion. Sixteen(57.1%) out of 28 patients had brain stem infarctions demonstrated by initial DWI. In the remaining 12 cases, no obvious ischemic lesion was evident on initial DWI. Subsequent MRI studies obtained 127 hours, on average after the onset showed infarction in the medulla oblongata in 11 cases and in the pons in one case. Negative findings of DWI in the acute stage does not exclude possibility of the brain stem infarction, in particulary medulla oblongata infarction.

Adult↗
PubMed1999

Natural course of combined limb and palatal tremor caused by cerebellar-brain stem infarction.

After infarction of the left superior cerebellar peduncle and dentate nucleus, a patient developed tremor of the left upper limb beginning on the twelfth day followed by palatal tremor appearing 10 months after infarction. Surface electromyogram revealed a difference in the frequency of the tremor in the upper limb and soft palate. When the palatal tremor appeared, brain magnetic resonance T2-weighted images revealed high signal intensity of the contralateral, right inferior olivary nucleus. Subsequently, when the amplitude of palatal tremor became less severe, the high olivary signal intensity subsided whereas the hypertrophy of the nucleus remained. This patient provides useful information on the pathogenesis of skeletal and palatal tremor with brain stem or cerebellar lesions based on the differences in the onset and frequency of tremors and morphologic changes in the inferior olive.

Arm↗
PubMed2004

[Current use and possible future applications of the magnetization transfer technique in neuroradiology].

Magnetization transfer (MT) imaging is a special MR technique used for selective suppression of the MR signal of protons bound on macromolecules. The most important applications in neuroradiology are (1) detection of subtle changes in otherwise normal-appearing cerebral white matter, for instance in multiple sclerosis (MS), Wallerian degeneration, and hydrocephalus, (2) differentiation of white matter lesions with high signal on T (2)-weighted MR-images, like MS plaques, brain infarctions, and brain edema, (3) follow-up of cerebral white matter diseases using volumetric MT techniques, and (4) improvement in delineating of contrast enhancing brain lesions, such as cerebral metastases. We describe the physical rationale of the MT technique and present the most important current and possible future applications of MT imaging to answer clinical and scientific questions in neuroradiology.

AIDS Dementia Complex↗
PubMed2003

[Proliferation and differentiation of neural stem cells after cerebral infarction: an experimental study of adult rats].

OBJECTIVE: To investigate the proliferation and differentiation of neural stem cells after cerebral infarction(CI) in adult rats. METHODS: CI animal model was made by ligating the common carotid artery and external carotid artery and inserting a piece of nylon thread into the internal carotid artery among 100 male Wistar rats. Then the rats were randomly divided into 5 groups: group of I day after brain infarction (n = 20), group of 3 days after brain infarction (n = 20), group of 7 days after brain infarction (n = 20), group of 14 days after brain infarction (n = 20), and group of 28 days after brain infarction (n = 20). Twelve rats undergoing sham operation with a piece of nylon thread inserted only into the common carotid artery were used as controls. The rats were killed at different time points and their brains were taken out. The expression of bromodeoxyuridine (BrdU) and Musashil (both used to mark the dividing neural stem cells), and of glial fibrillary acidic protein (GFAP) and neuronal nuclear antigen (NeuN) (both used to mark the differentiating neural stem cells) were determined by immunohistochemistry and immunofluorescence staining. RESULTS: In the normal brain tissues, only a small amount of BrdU(+) cells were found in the hippocampus. One day after CI the number of BrdU(+) cells began to increase in the hippocampus at the CI side (P < 0.05), peaked 7 days after CI with a number 6 times that at the normal side, began to decrease 14 days after, and almost reached normal 28 days after. The number of BrdU(+)/Musashil(+) cells began to increase 1 day after CI (P < 0.05), peaked 7 days after, began to decrease 14 days after, and almost reached normal 28 days after. The number of BrdU(+)/GFAP(+) cells at the CI side remained almost unchanged after CI. The number of BrdU(+)/NeuN(+) cells began to increase 14 days after CI (P < 0.05) and peaked 38 days after. CONCLUSION: Cerebral infarction stimulates the proliferation of inherent neural stem cells and most proliferated neural stem cells differentiate into neurons.

Animals↗
PubMedDate not supplied

Characteristics and survival of patients with brain stem infarction.

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

Adult↗
PubMed2004

Demographic and CT scan features related to cognitive impairment in the first year after stroke.

OBJECTIVE: Little is known about the relation between stroke related features and cognitive performance over time when stroke patients with dementia or less severe cognitive disorders are considered separately. We aimed to study the features (computed tomography (CT) scan and demographic) that could be related to vascular cognitive impairment one, six, and 12 months after stroke. METHODS: A total of 176 patients with a first-ever brain infarct, a Mini Mental State Examination score > or = 15, age older than 40 years, and without pre-stroke dementia and other neurological or psychiatric disorders participated in this study. The following CT scan features were recorded: side of infarct, lacunar or territorial infarct, white matter lesions, silent infarcts, and brain atrophy. The demographic features studied were: age, level of education, and sex. Univariate and multivariate logistic regression analyses were performed to compare the three groups of patients (patients with dementia, patients with vascular cognitive impairment (VCI), and patients with vascular mild cognitive impairment (MCI)) with patients without cognitive disorders. RESULTS: At one month none of the variables were predictors of dementia; at six months older age (odds ratio (OR) 9.4), low education (OR 14.7), and territorial infarct (OR 10.6) predicted dementia; and at 12 months low education (OR 8.7) and pre-stroke cerebrovascular damage (OR 7.4) predicted dementia. Predictors of VCI were low education (OR 3.4) and territorial infarct (OR 2.4) at one month post stroke; older age (OR 4.3) and low education (OR 4.1) at six months; and older age (OR 3.5) at 12 months. Predictors of vascular MCI were low education (OR 4.96) and territorial infarct (OR 3.58) at one month; and older age and lower education at six months (OR 3.4 and 3.7, respectively) and at 12 months (OR 3.5 and 2.28, respectively). CONCLUSIONS: Territorial infarct, older age, and low educational level are predictors of cognitive disorders after stroke.

Adult↗
PubMed2005

Catheter redundancy in the aortic arch increases the risk of stroke in left subclavian arterial port-catheter systems.

PURPOSE: The stroke rate after left subclavian arterial port-catheter placement was compared in two groups: one with minimal redundancy of the catheter and one with pronounced redundancy in the aortic arch designed to minimize the likelihood of catheter dislocation. MATERIALS AND METHODS: One hundred forty-eight patients (102 men, 46 women; age range, 26-83 years; mean age, 64.3 years) with inoperable advanced liver cancers underwent percutaneous implantation of port-catheter systems via the left subclavian artery. In 33 patients, a pronounced redundancy of the catheter was intentionally looped in the aortic arch. Redundancy was intentionally avoided in the remaining 115 patients. The rates of brain infarction complications in these two groups were retrospectively compared. RESULTS: Among the 33 patients with pronounced redundant catheter looping, brain infarctions occurred in four cases (12.1%). In contrast, brain infarctions occurred in only three of the 115 patients with minimal redundant catheter looping (2.6%). The frequency of brain infarction complications was significantly higher in the patients with pronounced redundant catheter looping in the aortic arch than in patients with minimal pronounced redundant catheter looping (P = .044, Fisher exact test). CONCLUSION: Catheter redundancy in the aortic arch increases the risk of stroke in patients undergoing implantation of port-catheter systems via a left subclavian arterial approach for repeated hepatic arterial infusion chemotherapy.

Adult↗
PubMed1996

Impairments of the protein C system and fibrinolysis in infection-associated stroke.

BACKGROUND AND PURPOSE: Infection/inflammation appears to be an important predisposing risk factor for brain infarction, but little is known regarding underlying molecular mechanisms. We examined the hypothesis that patients with brain infarction preceded by infection/inflammation within 1 week could be identified by a distinctive procoagulant laboratory profile characterized by abnormalities in the protein C system and endogenous fibrinolysis. METHODS: We performed a case-control study examining the relationship between preceding systemic infectious/inflammatory syndromes and selected immunohematologic variables in 36 patients with acute brain infarction and 81 control subjects (community control subjects [n = 47] and hospitalized nonstroke neurological patient controls [n = 34]). RESULTS: The stroke group had a lower mean level of the circulating antithrombotic enzyme activated protein C (APC) (4.33 +/- 0.34% [log-transformed percentage of control value, mean +/- SD]) than community control subjects (4.51 +/- 0.27%, P < .02) or hospitalized neurological patient controls (4.57 +/- 0.31%, P < .005). The lowest circulating APC levels were found in the stroke group with antecedent infection/inflammation within 1 week preceding index brain infarction (4.23 +/- 0.4%, n = 12). Within the stroke group, circulating APC levels were inversely related to IgG isotype anticardiolipin antibody titers (r = -.55, P < .001). Only the stroke group with infection/inflammation within 1 week had elevated plasma C4b binding protein compared with control subjects (141 +/- 61% versus 112 +/- 44%, P < .05). Stroke patients with antecedent infection/inflammation had a distinctively lower ratio of active tissue plasminogen activator to plasminogen activator inhibitor (0.11 +/- 0.04, n = 9) than other stroke patients (0.19 +/- 0.06, n = 9, P < .01) and control subjects (0.22 +/- 0.16, n = 17, P < .02). CONCLUSIONS: Impairments in the protein C pathway and endogenous fibrinolysis may contribute to the increased risk for brain infarction after recent (< or = 1 week) infection/inflammation. A decrease in the circulating anticoagulant APC may be related to elevated antiphospholipid antibody titers.

Antibodies, Anticardiolipin↗
PubMed2001

[Cerebrovascular emergency in neuroradiology].

Common causes to consultate a neuroradiologist in case of emergencies are trauma, brain infarction, or intracranial bleeding. Patients with brain infarction need a rapid assessment of the potentially nonnecrotic area within the ischaemic lesion. If haemorrhage, mostly occurring in the form of subarachnoid bleeding, is suspected, the source of bleeding has to be detected. With cranial computed tomography (CT) a thorough evaluation and staging of ischaemic stroke is possible with respect to thrombolysis. To detect irreversible damage of brain tissue, a combined perfusion-diffusion MRI should be performed.

Brain Infarction↗
PubMed1999

Prediction of in-hospital mortality after first-ever stroke: the Lausanne Stroke Registry.

We aimed to study in-hospital mortality after a first-ever stroke (brain infarction or parenchymatous hemorrhage) and to determine its predictors using easily obtainable variables. The main outcome measure was vital status at hospital discharge. Clinical features and type of stroke, with a particular emphasis on age, stroke topography and presumed causes of stroke, were studied in 3362 consecutive patients from the Lausanne Stroke Registry. Overall mortality was 4.8%. Brain hemorrhage mortality was 14.4% (48/333) and brain infarction mortality was 3.70% (112/3029). Localizations with high mortality included infratentorial (17.5%) and deep hemispheric (15.9%) territories for brain hemorrhage and, for brain infarction, multiple localizations in the posterior circulation (18.4%) and large middle cerebral artery territory (15.5%). Presumed causes of stroke associated with high mortality included saccular aneurysm (58.3%) and hypertensive arteriopathy (13.0%) for brain hemorrhage and, for brain infarction, dissection (10.4%), arteritis (8.3%), hematologic conditions (6.7%) and coexisting arterial and cardiac sources of embolism (5.2%). Multivariate logistic analysis showed that impaired consciousness on admission and limb weakness were good predictors of mortality for brain hemorrhage, while impaired consciousness and the cumulative effect of progressive worsening, limb weakness, left ventricular hypertrophy, past history of cardiac arrhythmia and previous transient ischemic attack were predictors of mortality for brain infarction. Age was not an independent predictor of stroke mortality, but for brain infarction the number of cumulative factors considered in the model increased with age. Our study shows that several factors associated with death risk are available during the first few hours after onset of stroke. Age alone is not critical, although its interaction with other factors should be considered.

Adolescent↗
PubMed1999

Evaluation of reperfusion and recovery of brain function before and after intracarotid arterial urokinase therapy in acute cerebral infarction with brain SPECT.

PURPOSE: Perfusion defects can be demonstrated reliably at an early stage with regional cerebral blood flow studies using SPECT. The administration of thrombolytic therapy in ischemic stroke is targeted at restoring cerebral perfusion immediately, leading to salvage of ischemic penumbra, smaller infarct size, and improved clinical outcome. This study considered the role of brain perfusion SPECT in the evaluation of reperfusion and brain function recovery of the infarcted area after early recanalization (less than 6 hours) of the occluded artery using intracarotid arterial urokinase therapy (ICAU). METHODS: Intracranial artery occlusion was confirmed in seven patients using emergency carotid angiography performed within the initial 6-hour period. Intracarotid arterial urokinase (500,000 to 800,000 units) was administered into the occluded arterial system (the left middle cerebral artery in four and the right middle cerebral artery in three patients). CT scanning was performed when the patients arrived in the emergency department and was repeated 24 to 48 hours after ICAU and at 7 days or earlier if clinically indicated. All patients had two SPECT studies, the first before urokinase administration and the second 24 or 48 hours later. RESULTS: Complete recanalization of the occluded vessels was seen in one patient after ICAU, effective partial recanalization was achieved in four patients, and minimal recanalization occurred in the other two. Before ICAU, Tc-99m HMPAO brain SPECT showed decreased uptake of the infarcted area in all patients, whereas the follow-up brain SPECT performed 24 or 48 hours after ICAU revealed improvement in the uptake of the recanalized area on qualitative and semiquantitative assessments using an asymmetry index, suggestive of brain function recovery and clinical improvement. Hemorrhagic transformation adjacent to the reperfused regions occurred in two patients with partial recanalization of the left middle cerebral artery. CONCLUSIONS: Reperfusion of the recanalized area and brain function recovery could be achieved if the occluded artery is recanalized within the initial 6-hour period using ICAU, and this was documented using brain perfusion SPECT without a delay in the therapeutic time window. Because the number of patients we studied was limited, further study is necessary to evaluate the effect of ICAU and to determine its prognostic significance.

Acute Disease↗