Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Brain Infarction”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,423 records · Page 79Linked to original sources

Relevance of computerized electroencephalographic topography (brain mapping) in ischemic stroke.

BACKGROUND AND AIMS: Computerized electroencephalographic topography (CET) (brain mapping) is a non-invasive, spatially oriented procedure for depicting amplitude and frequency patterns by two-dimensional color-coded frequency and amplitude display of the electroencephalograph (EEG). MATERIAL AND METHODS: We prospectively studied the relationship between CT scan lesions, conventional EEG and brain mapping in 40 patients with ischemic stroke within 1 week of onset. EEG and brain mapping was done within 24 hours of doing CT scan. RESULTS: There were 32 males and 8 females and the mean age was 56 years (range 27-75 years). CET/EEG was normal in 2 patients with capsular infarct. Brain mapping showed abnormalities (most commonly low-frequency high-amplitude changes) in 95% of patients, whereas EEG abnormalities were seen in only 40%. Brain mapping abnormalities were appropriate to the side of the CT scan lesion in 20 (52.63%) patients and were present bilaterally n 18 (47.37%) patients. Brain mapping abnormalities were ipsilateral to the side of the CT lesion when the lesion was < 2 cm in diameter and they were bi-hemispherical when the CT lesion was > 2 cm in diameter. CONCLUSIONS: There was no correlation between motor deficits and brain map abnormalities.

Adult↗

[Wallenberg syndrome in childhood secondary to the striking by lightening].

Wallenberg's Syndrome (WS) is exceptional in childhood. We present a case of a 10 year-old girl with a WS caused by an embolism in the right lateral portion of the medulla secondary to an electrofulguration, but with an unusual progressive outcome, developing clinical signs of medial medullar injury, leading even into a respiratory failure 30 days after admittance. She only became stable after surgical lesion decompression. There was no evidence of vascular malformation, finding only a great oedema. The pathology only showed changes compatible with brain infarction. This case makes again clear the superiority of MRI upon CT-scan to diagnose a WS. We think that the unusual progression of the lesion was due to great medullar oedema found on surgery, involving the brain regional flow.

Cerebrovascular Circulation↗

Neurological aspects of antiphospholipid antibody syndrome.

Antiphospholipid antibodies (aPL) have been associated with a variety of neurological disorders, mostly linked to focal neuroparenchymal ischemia or infarction. Cerebral ischemia associated with the antiphospholipid syndrome (APS) occurs at a younger age than typical atherothrombotic cerebrovascular disease, is often recurrent, and high positive GPL values are usually linked to the presence of a lupus anticoagulant. When other features of the syndrome are not present and cerebral ischemia occurs only associated with anticardiolipin immunoreactivity, there appears to be no discerning features of these patients unless GPL > 40 for which recurrent thrombo-occlusive events appear to occur more frequently. Other neurological manifestations associated with aPL include cerebral venous sinus thrombosis, ocular ischemia, dementia, including ischemic encephalopathy, and chorea. The role of aPL in migrainous events is controversial and may not play a role in recent, large case-controlled studies. Most seizures in patients harboring aPL are associated with focal brain infarction.

Antiphospholipid Syndrome↗

Does contralateral carotid occlusion influence neurologic fate of carotid endarterectomy?

Divergent opinions regarding operative risks and late prognosis of patients undergoing endarterectomy for carotid stenosis with contralateral carotid occlusion have prompted a review of the experience at Emory University Hospital from Jan. 1, 1978, through Dec. 31, 1982. Fifty-four patients (37 men, 17 women; mean age 63 years) who underwent carotid endarterectomy (CEA) with contralateral carotid occlusion (group I) were compared with 410 demographically similar patients without contralateral carotid occlusion (group II) who underwent 503 CEAs during the same interval. CEA indications in group I were the following and were proportionately similar to those of group II: hemispheric transient ischemic attacks, 22 patients; asymptomatic stenosis, 12 patients; nonhemispheric symptoms, 11 patients; previous cerebral infarction, eight patients; and vascular tinnitus, one patient. General anesthesia, routine intraluminal shunting, systemic heparinization, and arteriotomy closure without patch were routinely employed in both groups. Three patients in group I suffered permanent neurologic deficits after operation (5.6%) and two had transient postoperative deficits with complete recovery. Ten patients (2.0%) in group II suffered permanent neurologic deficits and 10 patients experienced transient neurologic events after operation. Neither the transient nor the permanent neurologic deficit rates were statistically different (p greater than 0.05; Fisher exact test) in the two groups. Operative mortality rates for group I and group II were 0% and 0.8%, respectively, and were not significantly different (p greater than 0.10; Fisher exact test). Late postoperative ischemic brain infarctions occurred in two patients in group I (3.8%) and in 13 patients (3.6%) in group II (p greater than 0.10; Fisher exact test). Kaplan-Meier survival analyses were virtually identical in both groups, with the majority of deaths caused by cardiac occlusion may undergo CEA with morbidity and mortality rates similar to those without contralateral occlusions. Contralateral carotid occlusion does not necessarily portend an unfavorable early or late prognosis after CEA.

Adult↗

Acute neurological complications after liver transplantation with particular reference to intraoperative cerebral air embolus.

Nine of 48 adult patients who underwent orthotopic liver transplantation developed significant clinical neurological abnormalities recognized shortly after operation. Decrease in consciousness occurred with resultant coma, focal and generalized seizures and the occasional appearance of a state of akinetic mutism. Neuropathological abnormalities consisted of multifocal areas of infarction in cerebral cortex and basal ganglia in five patients, central pontine myelinolysis in five (often more extensive than usually reported), Wernicke's encephalopathy in three, glial nodules in two, and fungal abscesses in one. Alzheimer II astrocytosis was found in all brains available for retrospective study. There was direct evidence in two of the patients that air embolization from the homografts had occurred. Correlation of this with the brain infarcts in these and other cases seems reasonable. The ease with which air passed to the systemic circulation is explicable by the right to left venous--arterial shunts that are common in chronic liver disease. With the delination of this cause for the neurologic complications, measures to prevent it in future cases have been described.

Adolescent↗

Early life linguistic ability, late life cognitive function, and neuropathology: findings from the Nun Study.

The relationships between early life variables, cognitive function, and neuropathology were examined in participants in the Nun Study who were between the ages of 75 and 95. Our early life variable was idea density, which is a measure of linguistic ability, derived from autobiographies written at a mean age of 22 years. Six discrete categories of cognitive function, including mild cognitive impairments, were evaluated, using the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) battery of cognitive tests. Neuropathologic data included Braak staging, neurofibrillary tangle and senile plaque counts, brain weight, degree of cerebral atrophy, severity of atherosclerosis, and the presence of brain infarcts. Early-life idea density was significantly related to the categories of late-life cognitive function, including mild cognitive impairments: low idea density was associated with greater impairment. Low idea density also was significantly associated with lower brain weight, higher degree of cerebral atrophy, more severe neurofibrillary pathology, and the likelihood of meeting neuropathologic criteria for Alzheimer's disease.

Age Factors↗

Effects of postischemic environment on transcription factor and serotonin receptor expression after permanent focal cortical ischemia in rats.

Housing rats in an enriched environment improves functional outcome after ischemic stroke, this may reflect neuronal plasticity in brain regions outside the lesion. Which components of the enriched environment that are of greatest importance for recovery after brain ischemia is uncertain. We have previously found that enriched environment and social interaction alone both improve functional recovery after focal cerebral ischemia, compared with isolated housing with voluntary wheel-running. In this study, the aim was to separate components of the enriched environment and investigate the effects on some potential mediators of improved functional recovery; such as the inducible transcription factors nerve growth factor-induced gene A (NGFI-A) and NGFI-B, and the glucocorticoid and serotonin systems. After permanent middle cerebral artery occlusion, rats were divided into four groups: individually housed with no equipment (deprived group), individually housed with free access to a running wheel (running group), housed together in a large cage with no equipment (social group) or in a large cage furnished with exchangeable bars, chains and other objects (enriched group). mRNA expression of inducible transcription factors, serotonin and glucocorticoid receptors was determined with in situ hybridisation 1 month after cerebral ischemia. Rats housed in enriched or social environments showed significantly higher mRNA expression of NGFI-A and NGFI-B in cortical regions outside the lesion and in the CA1 (cornu ammonis region of the hippocampus), compared with isolated rats with or without a running wheel. NGFI-A and NGFI-B mRNA expression in cortex and in CA1 was significantly correlated to functional outcome. 5-Hydroxytryptamine receptor 1A (5-HT(1A)) mRNA expression and binding, as well as 5-HT(2A) receptor mRNA expression were decreased in the hippocampus (CA4 region) of the running wheel rats. Mineralocorticoid receptor gene expression was increased in the dentate gyrus amongst wheel-running rats. No group differences were found in plasma corticosterone levels or mRNA levels of glucocorticoid receptor, corticotropin-releasing hormone, 5-HT(2C) or c-fos. In conclusion, we have found that social interaction is a major component of the enriched environment regarding the effects on NGFI-A and NGFI-B expression. These transcription factors may be important mediators of improved functional recovery after brain infarctions, induced by environmental enrichment.

Animals↗

[Two cases of impending herniation due to multiple traumatic acute subdural hematomas: combination of burr hole evacuation and craniotomy].

A contralateral extra-axial hematoma sometimes occurs during an operation on an acute subdural hematoma and may become fatal. Using a combined procedure of burr hole evacuation and craniotomy, we treated 2 cases of multiple traumatic acute subdural hematomas. Our policy for such cases is first to perform a burr hole evacuation for the acute subdural hematoma in the emergency room, while simultaneously preparing the operation room for a possible further operation. Next, we perform computed tomography (CT) of the brain. If the evacuation does not provide enough decompression, we either carry out a craniotomy at the same site, or, we observe the patient without resorting to craniotomy. However, if the patient's condition deteriorates, burr hole evacuation is repeated and/or craniotomy is carried out as soon as possible on the lesion at the already prepared operation room. Both of our patients received craniotomy for another subdural hematoma after the burr hole evacuation. Though his intracranial pressure was well managed during the acute stage, one of the patients died 21 days after the trauma due to an extensive brain infarction caused by vasospasm. The other regained consciousness and was able to walk 5 months after the trauma in spite of cerebral infarction from vasospasm. The possible mechanism of vasospasm in severe head injury is also discussed.

Adult↗

Simultaneous cerebral arterial and venous thrombosis.

Simultaneous thrombotic occlusion of cerebral arterial and venous systems in the same individual is rare. Three patients of stroke in whom autopsy revealed co-existing arterial and venous infarctions, major arterial occlusion (vertebral 1, internal carotid 1) and dural sinus and cortical vein thrombosis are reported. Role of infarcted brain, haemorrheological factors and alcohol in the pathogenesis of this rare event is highlighted.

Adult↗

[Comparison of brain scintigraphy with 99mTc-pertechnate and 99mTc-citrate].

20 patients with ultimately proven cerebral lesion were studied consecutively with 99mTc-pertechnetate and 99mTc-citrate. A comparison of the brain scans showed neoplastic lesions to be visualized more clearly with 99mTc-citrate, and vascular lesions to be demonstrated better with 99mTc-pertechnetate. Comparative brain scanning utilizing 99mTc-citrate and 99mTc-pertechnetate facilitates the differentiation between acute brain infarcts and neoplastic lesions which is difficult or may be impossible by cerebral computer tomography. The reduced radiation exposure from 99mTc-citrate and its superior usefulness in the visualization of neoplastic lesions suggest its use as the primary brain scanning agent.

Brain Diseases↗

Dynamics of regional brain metabolism and gene expression after middle cerebral artery occlusion in mice.

The evolution of brain infarcts during permanent occlusion of the middle cerebral artery (MCA) was studied in mice using multiparametric imaging techniques. Regional protein synthesis and the regional tissue content of ATP were measured on adjacent cryostat sections at increasing intervals after vascular occlusion ranging from 1 hour to 3 days. The observed changes were correlated with the expression of the mRNA of hsp70, c-fos, c-jun, and junB, as well as the distribution of DNA double-strand breaks visualized by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labelling (TUNEL). One hour after MCA occlusion, the tissue volume with suppressed protein synthesis was distinctly larger than that in which ATP was depleted. With ongoing ischemia time, the ATP-depleted area gradually expanded and, within 1 day, merged with the region of suppressed protein synthesis. Expression of hsp70 mRNA occurred mainly in the penumbra (defined as the region of suppressed protein synthesis but preserved ATP), peaking at 3 hours after vascular occlusion. Expression of the immediate-early genes c-jun, c-fos, and junB increased both in the penumbra and the periinfarct normal tissue already at 1 hour after vascular occlusion, with slightly different regional and temporal patterns for each of these genes. DNA fragmentations were clearly confined to neurons; they appeared after 1 day in the infarct core (defined as the region of suppressed ATP) and never were detected in the penumbra. The late appearance of TUNEL after infarcts had reached their final size and the absence in the penumbra points against a major pathogenetic role of apoptosis. Permanent MCA occlusion in mice thus produces a gradually expanding infarct, the final size of which is heralded by the early inhibition of protein synthesis.

Adenosine Triphosphate↗

Hereditary vascular dementia linked to notch 3 mutations. CADASIL in British families.

The most common form of familial vascular dementia is considered to be CADASIL or cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, which is now also increasingly manifest in the United Kingdom. CADASIL has been previously dubbed as a familial form of Binswanger disease. However, unlike in Binswanger disease CADASIL does not involve hypertension or other risk factors associated with cardiovascular disease. CADASIL appears to be essentially a disorder of the arteries that is linked to single missense mutations in the NOTCH 3 gene locus on chromosome 19. The pathogenesis of the disorder or the genetic mechanism leading to brain infarcts and dementia is not known. The elucidation of the microvascular pathology evident in CADASIL may be an interesting way to delineate effects of defective genes on brain cells from systemic vascular influences.

Cardiovascular Diseases↗

Brain ischemia and infarction positively visualized by pyruvate-1-11C using positron-emission tomography.

We describe positron-emission tomography (PET) scintigraphic findings obtained using pyruvate-1-11C in eight patients with cerebral ischemic hypoxia or infarction. The extraction of 11C by brain tissue from blood after an i.v. injection of 11C-pyruvate was very rapid, being almost complete after a single circulatory passage. Most ischemic lesions were found to be more or less deficient with regard to 11C-extraction capacity. With time, however, the ratio of 11C in ischemic tissue to that in normal tissue was inverted, and the ischemic lesion appeared as a 'hot' area in the scintigram. Very old infarcts did not exhibit this phenomenon. These observations indicate the usefulness of an 11C-pyruvate PET scan for the diagnosis of therapeutically restorable brain damage.

Adult↗

Effects of naloxone on lactate, pyruvate metabolism and antioxidant enzyme activity in rat cerebral ischemia/reperfusion.

Whether naloxone may modulate energy metabolism and endogenous antioxidant enzyme activities in ischemic cortex was studied. Cerebral ischemia/reperfusion (I/R) was produced by occluding two common carotid arteries and the right middle cerebral artery for 90 min followed by reperfusion in anesthetized Sprague-Dawley rats. Both pre-treatment (0.03 or 0.3 mg) and post-treatment (0.3 mg) of naloxone by intracerebroventricular infusion significantly reduced cortical infarct volumes. Pre-treatment with 0.03 mg reduced ischemia-induced suppression of extracellular pyruvate level and enhancement of lactate/pyruvate ratio as well as cerebral I/R-induced increases of endogenous catalase, glutathione peroxidase, and manganese superoxide dismutase activities. In conclusion, neuroprotective effects of naloxone in terms of reducing brain infarction involve attenuation of the disturbance of cellular functions following cerebral I/R via restoration of mitochondrial activities or energy metabolism.

Animals↗

Train duration effects on perception: sensory deficit, neglect, and cerebral lateralization.

The mechanisms of conscious perception are uncertain. In a preliminary study, dramatic effects of train duration on perception in a patient with right brain stroke were noted. In this study, the mechanisms of train duration on perception of peripheral somatosensory stimuli are examined. Subjects included healthy adults and patients with right brain infarctions. Train duration effects on perception were examined in relation to cerebral infarction, handedness, age, elevated peripheral threshold via bupivacaine, and impaired attention via diazepam or scopolamine. Perceptual thresholds to electrical pulses on the hand decreased as train duration increased, but only over the first several hundred milliseconds. Compared to controls, right brain stroke patients showed much greater lowering of threshold in the affected hand as train duration was extended. Age and bupivacaine elevated thresholds, but had little or no influence on train duration effects. Diazepam and scopolamine had no effect on thresholds. Thresholds were lower in the left than right hand of healthy dextral subjects, irrespective of age. Sinistral subjects had less left/right asymmetry. Increased train duration effect in patients is not explained by a primary elevation in threshold or by impaired vigilance. Lower perceptual thresholds in the left hand of healthy dextral subjects is consistent with right cerebral dominance for externally directed attention.

Adjuvants, Anesthesia↗

The protective effect of combined administration of anti-oxidants and perfluorochemicals on cerebral ischemia.

We previously published results of investigations which indicated that the combination of mannitol, which acts as a free radical scavenger, and perfluorochemicals (PFC), which have a strong oxygen-carrying capacity, can be therapeutic in cases of brain infarction. The present experiment tested the hypothesis that the effectiveness of such treatment could be increased by an optimal combination of such scavengers and other chemicals. Fifty-two dogs were used, employing the "canine model of a completely ischemic brain regulated with the perfusion method." A total of six drugs with free radical scavenger capacities were tested: mannitol, vitamin E, vitamin C, Nizofenone (Y-9197), dexamethasone (DEXA) and suloctidil (MY-103). These drugs were administered intravenously 15 minutes prior to the production of ischemia, when cerebral blood flow was reduced to one-tenth its normal volume. After one hour, recirculation was allowed and the recovery of electrical activity of the brain observed for three hours. Judged by the degree of recovery of brain electrical activity, five drugs were considered to have protective effect against brain ischemia: mannitol, vitamin E, MY-103, DEXA and Y-9197. Among these five drugs, mannitol, vitamin E and DEXA are known to be safe and easily used clinically. The combined administration of these three drugs, together with PFC, was also investigated. It was found that the speed and degree of recovery of brain electrical activity were greater when these drugs were given together than when one was administered alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Mild to moderate atheromatous disease of the thoracic aorta and new ischemic brain lesions after conventional coronary artery bypass graft surgery.

BACKGROUND AND PURPOSE: The presence of new ischemic brain infarcts, detected by diffusion-weighted magnetic resonance imaging (DW-MRI), have been reported in considerable number of patients after cardiac surgery. We sought to determine the role of proximal thoracic aortic atheroma in predicting embolic events and new ischemic brain lesions in patients undergoing conventional coronary revascularization surgery. METHODS: Transesophageal echocardiography and epiaortic scanning was performed to assess the severity of aortic atherosclerosis in the ascending aorta and the aortic arch. Patients were allocated to either low-risk group, (intimal thickness < or =2mm), or high-risk group (intimal thickness >2mm). Transcranial Doppler was used to monitor the middle cerebral artery. DW-MRI was performed 3-7 days after surgery. The NEECHAM Confusion Scale was used for assessment and monitoring patient consciousness level. RESULTS: Patients in the high-risk group were considerably older; 71+/-6 (n=38) versus 67+/-6 (n=72) years, P=0.004 and were more likely to have impaired left ventricular function. Confusion was present in 6 (16%) patients in the high-risk group and 5 (7%) patients in the low-risk group. Patients in the high-risk group had a three-fold increase in median embolic count, 223.5 versus 70.0, P=0.0003. DW-MRI detected brain lesions were only present in patients from high-risk group, 61.5 versus 0%, P<0.0001. There was significant correlation between the NEECHAM scores and embolic count in the high-risk group; r=0.63, P<0.001. CONCLUSIONS: The findings of this investigation suggest that mild to moderate atheromatous disease of the ascending aorta and the aortic arch (intimal thickness >2mm) is a major contributor to ischemic brain injury after cardiac surgery.

Aged↗