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1.
Lancet ; 403(10444): 2597-2605, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38768626

RESUMEN

BACKGROUND: Individuals with minor ischaemic stroke and intracranial occlusion are at increased risk of poor outcomes. Intravenous thrombolysis with tenecteplase might improve outcomes in this population. We aimed to test the superiority of intravenous tenecteplase over non-thrombolytic standard of care in patients with minor ischaemic stroke and intracranial occlusion or focal perfusion abnormality. METHODS: In this multicentre, prospective, parallel group, open label with blinded outcome assessment, randomised controlled trial, adult patients (aged ≥18 years) were included at 48 hospitals in Australia, Austria, Brazil, Canada, Finland, Ireland, New Zealand, Singapore, Spain, and the UK. Eligible patients with minor acute ischaemic stroke (National Institutes of Health Stroke Scale score 0-5) and intracranial occlusion or focal perfusion abnormality were enrolled within 12 h from stroke onset. Participants were randomly assigned (1:1), using a minimal sufficient balance algorithm to intravenous tenecteplase (0·25 mg/kg) or non-thrombolytic standard of care (control). Primary outcome was a return to baseline functioning on pre-morbid modified Rankin Scale score in the intention-to-treat (ITT) population (all patients randomly assigned to a treatment group and who did not withdraw consent to participate) assessed at 90 days. Safety outcomes were reported in the ITT population and included symptomatic intracranial haemorrhage and death. This trial is registered with ClinicalTrials.gov, NCT02398656, and is closed to accrual. FINDINGS: The trial was stopped early for futility. Between April 27, 2015, and Jan 19, 2024, 886 patients were enrolled; 369 (42%) were female and 517 (58%) were male. 454 (51%) were assigned to control and 432 (49%) to intravenous tenecteplase. The primary outcome occurred in 338 (75%) of 452 patients in the control group and 309 (72%) of 432 in the tenecteplase group (risk ratio [RR] 0·96, 95% CI 0·88-1·04, p=0·29). More patients died in the tenecteplase group (20 deaths [5%]) than in the control group (five deaths [1%]; adjusted hazard ratio 3·8; 95% CI 1·4-10·2, p=0·0085). There were eight (2%) symptomatic intracranial haemorrhages in the tenecteplase group versus two (<1%) in the control group (RR 4·2; 95% CI 0·9-19·7, p=0·059). INTERPRETATION: There was no benefit and possible harm from treatment with intravenous tenecteplase. Patients with minor stroke and intracranial occlusion should not be routinely treated with intravenous thrombolysis. FUNDING: Heart and Stroke Foundation of Canada, Canadian Institutes of Health Research, and the British Heart Foundation.


Asunto(s)
Fibrinolíticos , Accidente Cerebrovascular Isquémico , Tenecteplasa , Humanos , Tenecteplasa/uso terapéutico , Tenecteplasa/administración & dosificación , Masculino , Femenino , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Fibrinolíticos/uso terapéutico , Fibrinolíticos/administración & dosificación , Anciano , Persona de Mediana Edad , Resultado del Tratamiento , Estudios Prospectivos , Nivel de Atención , Activador de Tejido Plasminógeno/uso terapéutico , Activador de Tejido Plasminógeno/administración & dosificación , Terapia Trombolítica/métodos
2.
J Neurol Neurosurg Psychiatry ; 93(3): 238-245, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35115388

RESUMEN

Treatment with endovascular therapy in the extended time window for acute ischaemic stroke with large vessel occlusion involves stringent selection criteria based on the two landmark studies DAWN and DEFUSE3. Current protocols typically include the requirement of advanced perfusion imaging which may exclude a substantial proportion of patients from receiving a potentially effective therapy. Efforts to offer endovascular reperfusion therapies to all appropriate candidates may be facilitated by the use of simplified imaging selection paradigms with widely available basic imaging techniques, such as non-contrast CT and CT angiography. Currently available evidence from our literature review suggests that patients meeting simplified imaging selection criteria may benefit as much as those patients selected using advanced imaging techniques (CT perfusion or MRI) from endovascular therapy in the extended time window. A comprehensive understanding of the role of imaging in patient selection is critical to optimising access to endovascular therapy in the extended time window and improving outcomes in acute stroke. This article provides an overview on current developments and future directions in this emerging area.


Asunto(s)
Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico/terapia , Trombectomía , Humanos , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Imagen por Resonancia Magnética , Neuroimagen , Selección de Paciente , Factores de Tiempo , Tomografía Computarizada por Rayos X
3.
Neurobiol Dis ; 161: 105540, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34751140

RESUMEN

BACKGROUND: Alzheimer's disease (AD) is a neurodegenerative disease that exacts a huge toll on the patient, the healthcare system and society in general. Abundance and morphology of protein aggregates such as amyloid ß plaques and tau tangles, along with cortical atrophy and gliosis are used as measures to assess the changes in the brain induced by the disease. Not all of these parameters have a direct correlation with cognitive decline. Studies have shown that only particular protein conformers can be the main drivers of disease progression, and conventional approaches are unable to distinguish different conformations of disease-relevant proteins. METHODS AND RESULTS: Using the fluorescent amyloid probes K114 and CRANAD-3 and spectral confocal microscopy, we examined formalin-fixed paraffin-embedded brain samples from different control and AD cases. Based on the emission spectra of the probes used in this study, we found that certain spectral signatures can be correlated with different aggregates formed by different proteins. The combination of spectral imaging and advanced image analysis tools allowed us to detect variability of protein deposits across the samples. CONCLUSION: Our proposed method offers a quicker and easier neuropathological assessment of tissue samples, as well as introducing an additional parameter by which protein aggregates can be discriminated.


Asunto(s)
Enfermedad de Alzheimer , Enfermedades Neurodegenerativas , Sustancia Blanca , Humanos , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Fluorescencia , Enfermedades Neurodegenerativas/diagnóstico por imagen , Enfermedades Neurodegenerativas/metabolismo , Placa Amiloide/metabolismo , Estirenos , Proteínas tau/metabolismo , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología
4.
Sensors (Basel) ; 21(7)2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33915960

RESUMEN

Hippocampus atrophy is an early structural feature that can be measured from magnetic resonance imaging (MRI) to improve the diagnosis of neurological diseases. An accurate and robust standardized hippocampus segmentation method is required for reliable atrophy assessment. The aim of this work was to develop and evaluate an automatic segmentation tool (DeepHarp) for hippocampus delineation according to the ADNI harmonized hippocampal protocol (HarP). DeepHarp utilizes a two-step process. First, the approximate location of the hippocampus is identified in T1-weighted MRI datasets using an atlas-based approach, which is used to crop the images to a region-of-interest (ROI) containing the hippocampus. In the second step, a convolutional neural network trained using datasets with corresponding manual hippocampus annotations is used to segment the hippocampus from the cropped ROI. The proposed method was developed and validated using 107 datasets with manually segmented hippocampi according to the ADNI-HarP standard as well as 114 multi-center datasets of patients with Alzheimer's disease, mild cognitive impairment, cerebrovascular disease, and healthy controls. Twenty-three independent datasets manually segmented according to the ADNI-HarP protocol were used for testing to assess the accuracy, while an independent test-retest dataset was used to assess precision. The proposed DeepHarp method achieved a mean Dice similarity score of 0.88, which was significantly better than four other established hippocampus segmentation methods used for comparison. At the same time, the proposed method also achieved a high test-retest precision (mean Dice score: 0.95). In conclusion, DeepHarp can automatically segment the hippocampus from T1-weighted MRI datasets according to the ADNI-HarP protocol with high accuracy and robustness, which can aid atrophy measurements in a variety of pathologies.


Asunto(s)
Enfermedad de Alzheimer , Procesamiento de Imagen Asistido por Computador , Enfermedad de Alzheimer/diagnóstico por imagen , Hipocampo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Redes Neurales de la Computación
5.
J Neurochem ; 144(5): 565-581, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28734089

RESUMEN

The incidence of dementia is expected to double in the next 20 years and will contribute to heavy social and economic burden. Dementia is caused by neuronal loss that leads to brain atrophy years before symptoms manifest. Currently, no cure exists and extensive efforts are being made to mitigate cognitive impairment in late life in order to reduce the burden on patients, caregivers, and society. The most common type of dementia, Alzheimer's disease (AD), and vascular dementia (VaD) often co-exists in the brain and shares common, modifiable risk factors, which are targeted in numerous secondary prevention trials. There is a growing need for non-pharmacological interventions and infrastructural support from governments to encourage psychosocial and behavioral interventions. Secondary prevention trials need to be redesigned based on the risk profile of individual subjects, which require the use of validated and standardized clinical, biological, and neuroimaging biomarkers. Multi-domain approaches have been proposed in high-risk populations that target optimal treatment; clinical trials need to recruit individuals at the highest risk of dementia before symptoms develop, thereby identifying an enriched disease group to test preventative and disease modifying strategies. The underlying aim should be to reduce microscopic brain tissue loss by modifying vascular and lifestyle risk factors over a relatively short period of time, thus optimizing the opportunity for preventing dementia in the future. Collaboration between international research groups is of key importance to the optimal use and allocation of existing resources, and the development of new techniques in preventing dementia. This article is part of the Special Issue "Vascular Dementia".


Asunto(s)
Demencia Vascular/prevención & control , Biomarcadores , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Demencia Vascular/diagnóstico por imagen , Demencia Vascular/patología , Humanos , Estilo de Vida , Factores de Riesgo
6.
N Engl J Med ; 372(11): 1019-30, 2015 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-25671798

RESUMEN

BACKGROUND: Among patients with a proximal vessel occlusion in the anterior circulation, 60 to 80% of patients die within 90 days after stroke onset or do not regain functional independence despite alteplase treatment. We evaluated rapid endovascular treatment in addition to standard care in patients with acute ischemic stroke with a small infarct core, a proximal intracranial arterial occlusion, and moderate-to-good collateral circulation. METHODS: We randomly assigned participants to receive standard care (control group) or standard care plus endovascular treatment with the use of available thrombectomy devices (intervention group). Patients with a proximal intracranial occlusion in the anterior circulation were included up to 12 hours after symptom onset. Patients with a large infarct core or poor collateral circulation on computed tomography (CT) and CT angiography were excluded. Workflow times were measured against predetermined targets. The primary outcome was the score on the modified Rankin scale (range, 0 [no symptoms] to 6 [death]) at 90 days. A proportional odds model was used to calculate the common odds ratio as a measure of the likelihood that the intervention would lead to lower scores on the modified Rankin scale than would control care (shift analysis). RESULTS: The trial was stopped early because of efficacy. At 22 centers worldwide, 316 participants were enrolled, of whom 238 received intravenous alteplase (120 in the intervention group and 118 in the control group). In the intervention group, the median time from study CT of the head to first reperfusion was 84 minutes. The rate of functional independence (90-day modified Rankin score of 0 to 2) was increased with the intervention (53.0%, vs. 29.3% in the control group; P<0.001). The primary outcome favored the intervention (common odds ratio, 2.6; 95% confidence interval, 1.7 to 3.8; P<0.001), and the intervention was associated with reduced mortality (10.4%, vs. 19.0% in the control group; P=0.04). Symptomatic intracerebral hemorrhage occurred in 3.6% of participants in intervention group and 2.7% of participants in control group (P=0.75). CONCLUSIONS: Among patients with acute ischemic stroke with a proximal vessel occlusion, a small infarct core, and moderate-to-good collateral circulation, rapid endovascular treatment improved functional outcomes and reduced mortality. (Funded by Covidien and others; ESCAPE ClinicalTrials.gov number, NCT01778335.).


Asunto(s)
Procedimientos Endovasculares , Accidente Cerebrovascular/terapia , Trombectomía , Anciano , Anciano de 80 o más Años , Angiografía de Substracción Digital , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/terapia , Hemorragia Cerebral/inducido químicamente , Terapia Combinada , Femenino , Fibrinolíticos/uso terapéutico , Humanos , Análisis de Intención de Tratar , Masculino , Persona de Mediana Edad , Reperfusión , Método Simple Ciego , Stents , Accidente Cerebrovascular/mortalidad , Trombectomía/instrumentación , Activador de Tejido Plasminógeno/uso terapéutico , Tomografía Computarizada por Rayos X
7.
Biomarkers ; 23(8): 793-803, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30010432

RESUMEN

OBJECTIVE: To validate our previously developed 16 plasma-protein biomarker panel to differentiate between transient ischaemic attack (TIA) and non-cerebrovascular emergency department (ED) patients. METHOD: Two consecutive cohorts of ED patients prospectively enrolled at two urban medical centers into the second phase of SpecTRA study (training, cohort 2A, n = 575; test, cohort 2B, n = 528). Plasma samples were analyzed using liquid chromatography/multiple reaction monitoring-mass spectrometry. Logistic regression models which fit cohort 2A were validated on cohort 2B. RESULTS: Three of the panel proteins failed quality control and were removed from the panel. During validation, panel models did not outperform a simple motor/speech (M/S) deficit variable. Post-hoc analyses suggested the measured behaviour of L-selectin and coagulation factor V contributed to poor model performance. Removal of these proteins increased the external performance of a model containing the panel and the M/S variable. CONCLUSIONS: Univariate analyses suggest insulin-like growth factor-binding protein 3 and serum paraoxonase/lactonase 3 are reliable and reproducible biomarkers for TIA status. Logistic regression models indicated L-selectin, apolipoprotein B-100, coagulation factor IX, and thrombospondin-1 to be significant multivariate predictors of TIA. We discuss multivariate feature subset analyses as an exploratory technique to better understand a panel's full predictive potential.


Asunto(s)
Biomarcadores/sangre , Ataque Isquémico Transitorio/sangre , Accidente Cerebrovascular/sangre , Anciano , Arildialquilfosfatasa/sangre , Diagnóstico Diferencial , Servicio de Urgencia en Hospital , Humanos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Ataque Isquémico Transitorio/diagnóstico , Modelos Logísticos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Proteómica/métodos , Accidente Cerebrovascular/diagnóstico , Investigación Biomédica Traslacional
8.
Int Psychogeriatr ; 30(2): 233-244, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28879833

RESUMEN

BACKGROUND: Mild behavioral impairment (MBI) describes later life acquired, sustained neuropsychiatric symptoms (NPS) in cognitively normal individuals or those with mild cognitive impairment (MCI), as an at-risk state for incident cognitive decline and dementia. We developed an operational definition of MBI and tested whether the presence of MBI was related to caregiver burden in patients with subjective cognitive decline (SCD) or MCI assessed at a memory clinic. METHODS: MBI was assessed in 282 consecutive memory clinic patients with SCD (n = 119) or MCI (n = 163) in accordance with the International Society to Advance Alzheimer's Research and Treatment - Alzheimer's Association (ISTAART-AA) research diagnostic criteria. We operationalized a definition of MBI using the Neuropsychiatric Inventory Questionnaire (NPI-Q). Caregiver burden was assessed using the Zarit caregiver burden scale. Generalized linear regression was used to model the effect of MBI domains on caregiver burden. RESULTS: While MBI was more prevalent in MCI (85.3%) than in SCD (76.5%), this difference was not statistically significant (p = 0.06). Prevalence estimates across MBI domains were affective dysregulation (77.8%); impulse control (64.4%); decreased motivation (51.7%); social inappropriateness (27.8%); and abnormal perception or thought content (8.7%). Affective dysregulation (p = 0.03) and decreased motivation (p=0.01) were more prevalent in MCI than SCD patients. Caregiver burden was 3.35 times higher when MBI was present after controlling for age, education, sex, and MCI (p < 0.0001). CONCLUSIONS: MBI was common in memory clinic patients without dementia and was associated with greater caregiver burden. These data show that MBI is a common and clinically relevant syndrome.


Asunto(s)
Síntomas Conductuales/epidemiología , Cuidadores/psicología , Disfunción Cognitiva/epidemiología , Demencia/epidemiología , Anciano , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/psicología , Demencia/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Prevalencia , Estudios Prospectivos
9.
BMC Geriatr ; 18(1): 163, 2018 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-30012102

RESUMEN

BACKGROUND: Late-life cognitive decline, caused by progressive neuronal loss leading to brain atrophy years before symptoms are detected, is expected to double in Canada over the next two decades. Cognitive impairment in late life is attributed to vascular and lifestyle related risk factors in mid-life in a substantial proportion of cases (50%), thereby providing an opportunity for effective prevention of cognitive decline if incipient disease is detected earlier. Patients presenting with transient ischemic attack (TIA) commonly display some degree of cognitive impairment and are at a 4-fold increased risk of dementia. In the Predementia Neuroimaging of Transient Ischemic Attack (PREVENT) study, we will address what disease processes (i.e., Alzheimer's vs. vascular disease) lead to neurodegeneration, brain atrophy, and cognitive decline, and whether imaging measurements of brain iron accumulation using quantitative susceptibility mapping predicts subsequent brain atrophy and cognitive decline. METHODS: A total of 440 subjects will be recruited for this study with 220 healthy subjects and 220 TIA patients. Early Alzheimer's pathology will be determined by cerebrospinal fluid samples (including tau, a marker of neuronal injury, and amyloid ß1-42) and by MR measurements of iron accumulation, a marker for Alzheimer's-related neurodegeneration. Small vessel disease will be identified by changes in white matter lesion volume. Predictors of advanced rates of cerebral and hippocampal atrophy at 1 and 3 years will include in vivo Alzheimer's disease pathology markers, and MRI measurements of brain iron accumulation and small vessel disease. Clinical and cognitive function will be assessed annually post-baseline for a period of 5-years using a clinical questionnaire and a battery of neuropsychological tests, respectively. DISCUSSION: The PREVENT study expects to demonstrate that TIA patients have increased early progressive rates of cerebral brain atrophy after TIA, before cognitive decline can be clinically detected. By developing and optimizing high-level machine learning models based on clinical data, image-based (quantitative susceptibility mapping, regional brain, and white matter lesion volumes) features, and cerebrospinal fluid biomarkers, PREVENT will provide a timely opportunity to identify individuals at greatest risk of late-life cognitive decline early in the course of disease, supporting future therapeutic strategies for the promotion of healthy aging.


Asunto(s)
Disfunción Cognitiva/etiología , Ataque Isquémico Transitorio/diagnóstico por imagen , Ataque Isquémico Transitorio/psicología , Imagen por Resonancia Magnética , Enfermedades Neurodegenerativas/diagnóstico por imagen , Enfermedades Neurodegenerativas/psicología , Anciano , Atrofia/patología , Encéfalo/patología , Canadá , Cognición , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/psicología , Femenino , Humanos , Ataque Isquémico Transitorio/patología , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Enfermedades Neurodegenerativas/patología , Neuroimagen , Pruebas Neuropsicológicas , Factores de Riesgo
10.
Stroke ; 48(4): 939-945, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28292870

RESUMEN

BACKGROUND AND PURPOSE: Within different brain regions, we determine the comparative value of multiphase computed tomographic angiography (mCTA) and computed tomographic perfusion (CTP) in predicting follow-up infarction. METHODS: Patients with M1-middle cerebral artery occlusions were prospectively included in this multicenter study. Regional analysis was performed for each patient within Alberta Stroke Program Early CT Score regions M2 to M6. Regional pial vessel filling was assessed on mCTA in 3 ways: (1) Washout of contrast within pial vessels; (2) Extent of maximal pial vessel enhancement compared with contralateral hemisphere; (3) Delay in maximal pial vessel enhancement compared with contralateral hemisphere. Cerebral blood flow, cerebral blood volume, and Tmax data were extracted within these Alberta Stroke Program Early CT Score regions. Twenty-four- to 36-hour magnetic resonance imaging/CT was assessed for infarct in each Alberta Stroke Program Early CT Score region (defined as >20% infarction within that region). Mixed effects logistic regression models were used to compare mCTA and CTP parameters when predicting brain infarction. Area under the receiver operating characteristics was used to assess discriminative value of statistical models. RESULTS: Seventy-seven patients were included. mCTA parameter washout and CTP parameter Tmax were significantly associated with follow-up infarction in all models (P<0.05). The area under the receiver operating characteristic for mCTA models ranged from 92% to 94% and was not different compared with all CTP models (P>0.05). Mean Tmax and cerebral blood volume values were significantly different between each washout score (P<0.01) and each delay score category (P<0.01). Mean Tmax, cerebral blood flow, and cerebral blood volume values were significantly different between each extent score category (P<0.05). CONCLUSIONS: Similar to CTP, multiphase CTA can be used to predict tissue fate regionally in acute ischemic stroke patients.


Asunto(s)
Isquemia Encefálica/diagnóstico por imagen , Infarto de la Arteria Cerebral Media/diagnóstico por imagen , Evaluación de Resultado en la Atención de Salud , Accidente Cerebrovascular/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Anciano , Anciano de 80 o más Años , Angiografía Cerebral/métodos , Angiografía por Tomografía Computarizada/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Imagen de Perfusión/métodos , Pronóstico , Estudios Prospectivos
11.
Stroke ; 47(3): 726-31, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26846862

RESUMEN

BACKGROUND AND PURPOSE: Few studies have examined predictors of cognitive impairment after minor ischemic stroke and transient ischemic attack (TIA). We examined clinical and imaging features associated with worse cognitive performance at 90 days. METHODS: TIA or patients with minor stroke underwent neuropsychological testing 90 days post event. Z scores were calculated for cognitive tests, and then grouped into domains of executive function (EF), psychomotor processing speed (PS), and memory. White matter hyperintensity and diffusion-weighted imaging volumes were measured on baseline magnetic resonance imaging. Ninety-day outcomes included modified Rankin Scale (mRS) and Centre for Epidemiological Studies Depression Scale (CES-D) score. RESULTS: Ninety-two patients were included, 76% male, 54% TIA, and mean age 65.1±12.0. Sixty-four percent were diffusion-weighted imaging positive. Median domain z scores were not significantly different from published norms (P>0.05): memory -0.03, EF -0.12, and PS -0.05. Patient performance ≥1 SD below normal was 20% on memory, 16% on PS, and 17% on EF. Cognitive scores did not differ by diagnosis (stroke versus TIA), stroke pathogenesis, presence of obstructive sleep apnea, and diffusion-weighted imaging or white matter hyperintensity volumes. In multivariable analyses, lower EF was associated with previous cortical infarct on magnetic resonance imaging (P=0.03), mRS score of >1; P=0.0003 and depressive symptoms (CES-D ≥16; P=0.03). Lower PS scores were associated with previous cortical infarct (P=0.02), acute bilateral positive diffusion-weighted imaging (P=0.02), mRS score of >1 (P=0.003), and CES-D ≥16 (P=0.03). CONCLUSIONS: Despite average-range cognitive performance in this TIA and population with minor stroke, we found associations of EF and PS with evidence of previous stroke, postevent disability, and depression.


Asunto(s)
Trastornos del Conocimiento/diagnóstico , Imagen de Difusión por Resonancia Magnética/tendencias , Ataque Isquémico Transitorio/diagnóstico , Pruebas Neuropsicológicas , Accidente Cerebrovascular/diagnóstico , Anciano , Trastornos del Conocimiento/epidemiología , Trastornos del Conocimiento/psicología , Femenino , Humanos , Ataque Isquémico Transitorio/epidemiología , Ataque Isquémico Transitorio/psicología , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/psicología
12.
Stroke ; 47(3): 777-81, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26892284

RESUMEN

BACKGROUND AND PURPOSE: The goal of reperfusion therapy in acute ischemic stroke is to limit brain infarction. The objective of this study was to investigate whether the beneficial effect of endovascular treatment on functional outcome could be explained by a reduction in post-treatment infarct volume. METHODS: The Endovascular Treatment for Small Core and Anterior Circulation Proximal Occlusion With Emphasis on Minimizing CT to Recanalization Times (ESCAPE) trial was a multicenter randomized open-label trial with blinded outcome evaluation. Among 315 enrolled subjects (endovascular treatment n=165; control n=150), 314 subject's infarct volumes at 24 to 48 hours on magnetic resonance imaging (n=254) or computed tomography (n=60) were measured. Post-treatment infarct volumes were compared by treatment assignment and recanalization/reperfusion status. Appropriate statistical models were used to assess relationship between baseline clinical and imaging variables, post-treatment infarct volume, and functional status at 90 days (modified Rankin Scale). RESULTS: Median post-treatment infarct volume in all subjects was 21 mL (interquartile range =65 mL), in the intervention arm, 15.5 mL (interquartile range =41.5 mL), and in the control arm, 33.5 mL (interquartile range =84 mL; P<0.01). Baseline National Institute of Health Stroke Scale (P<0.01), site of occlusion (P<0.01), baseline noncontrast computed tomographic scan Alberta Stroke Program Early CT score (ASPECTS) (P<0.01), and recanalization (P<0.01) were independently associated with post-treatment infarct volume, whereas age, sex, treatment type, intravenous alteplase, and time from onset to randomization were not (P>0.05). Post-treatment infarct volume (P<0.01) and delta National Institute of Health Stroke Scale (P<0.01) were independently associated with 90-day modified Rankin Scale, whereas laterality (left versus right) was not. CONCLUSIONS: These results support the primary results of the ESCAPE trial and show that the biological underpinning of the success of endovascular therapy is a reduction in infarct volume. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01778335.


Asunto(s)
Infarto Cerebral/diagnóstico , Infarto Cerebral/tratamiento farmacológico , Procedimientos Endovasculares/tendencias , Infusiones Intraarteriales/tendencias , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/tratamiento farmacológico , Procedimientos Endovasculares/métodos , Femenino , Estudios de Seguimiento , Humanos , Infusiones Intraarteriales/métodos , Masculino , Método Simple Ciego , Terapia Trombolítica/métodos , Terapia Trombolítica/tendencias , Activador de Tejido Plasminógeno/administración & dosificación , Resultado del Tratamiento
13.
Stroke ; 47(12): 2993-2998, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27834743

RESUMEN

BACKGROUND AND PURPOSE: Infarct in a new previously unaffected territory (INT) is a potential complication of endovascular treatment. We applied a recently proposed methodology to identify and classify INTs in the ESCAPE randomized controlled trial (Endovascular Treatment for Small Core and Anterior Circulation Proximal Occlusion With Emphasis on Minimizing CT to Recanalization Times). METHODS: The core laboratory identified INTs on 24-hour follow-up imaging, blinded to treatment allocation, after assessing all baseline imaging. INTs were classified into 3 types (I-III) and 2 subtypes (A/B) based on size and if catheter manipulation was likely performed across the vessel territory ostium. Logistic regression was used to understand the effect of multiple a priori identified variables on INT occurrence. Ordinal logistic regression was used to analyze the effect of INTs on modified Rankin Scale shift at 90 days. RESULTS: From 308 patients included, 14 INTs (4.5% overall; 2.8% on follow-up noncontrast computed tomography, 11.7% on follow-up magnetic resonance imaging) were identified (5.0% in endovascular treatment arm versus 4.0% in control arm [P=0.7]). The use of intravenous alteplase was associated with a 68% reduction in the odds of INT occurrence (3.0% with versus 9.1% without; odds ratio, 0.32; 95% confidence interval, 0.11-0.96; adjusted for age, sex, and treatment type). No other variables were associated with INTs. INT occurrence was associated with reduced probability of good clinical outcome (common odds ratio, 0.25; 95% confidence interval, 0.09-0.74; adjusted for age, type of treatment, and follow-up scan). CONCLUSIONS: INTs are uncommon, detected more frequently on follow-up magnetic resonance imaging, and affect clinical outcome. In experienced centers, endovascular treatment is likely not causal, whereas intravenous alteplase may be therapeutic. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01778335.


Asunto(s)
Infarto Cerebral/diagnóstico por imagen , Infarto Cerebral/terapia , Fibrinolíticos/uso terapéutico , Terapia Trombolítica/métodos , Activador de Tejido Plasminógeno/uso terapéutico , Infarto Cerebral/clasificación , Fibrinolíticos/efectos adversos , Humanos , Terapia Trombolítica/efectos adversos , Activador de Tejido Plasminógeno/efectos adversos
14.
BMC Neurosci ; 17(1): 28, 2016 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-27230275

RESUMEN

BACKGROUND: In the current study, a transient cerebral ischemia producing selective cell death was designated a mild ischemic insult. A comparable insult in humans is a transient ischemic attack (TIA) that is associated with functional recovery but can have imaging evidence of minor ischemic damage including cerebral atrophy. A TIA also predicts a high risk for early recurrence of a stroke or TIA and thus multiple ischemic insults are not uncommon. Not well understood is what the effect of differing recovery times between mild ischemic insults has on their pathophysiology. We investigated whether cumulative brain damage would differ if recurrence of a mild ischemic insult occurred at 1 or 3 days after a first insult. RESULTS: A transient episode of middle cerebral artery occlusion via microclip was produced to elicit mild ischemic changes-predominantly scattered necrosis. This was followed 1 or 3 days later by a repeat of the same insult. Brain damage assessed histologically 7 days later was substantially greater in the 1 day recurrent group than the 3 days recurrent group, with areas of damage consisting predominantly of regions of incomplete infarction and pannecrosis in the 1 day group but predominantly regions of selective necrosis and smaller areas of incomplete infarction in the 3 days group (P < 0.05). Enhanced injury was reflected by greater number of cells staining for macrophages/microglia with ED1 and greater alterations in GFAP staining of reactive astrocytes in the 1 day than 3 days recurrent groups. The differential susceptibility to injury did not correspond to higher levels of injurious factors present at the time of the second insult such as BBB disruption or increased cytokines (tumor necrosis factor). Microglial activation, with potential for some beneficial effects, appeared greater at 3 days than 1 day. Also blood analysis demonstrated changes that included an acute increase in granulocytes and decrease in platelets at 1 day compared to 3 days post transient ischemia. CONCLUSIONS: Dynamic changes in multiple inflammatory responses likely contribute to the time dependence of the extent of damage produced by recurrent mild ischemic insults. The time of mild stroke recurrence is crucial with early recurrence producing greater damage than subacute recurrence and this supports urgency for determining and implementing optimal stroke management directly after a TIA.


Asunto(s)
Isquemia Encefálica/patología , Encéfalo/patología , Enfermedad Aguda , Animales , Astrocitos/patología , Biomarcadores/sangre , Encéfalo/inmunología , Isquemia Encefálica/sangre , Isquemia Encefálica/inmunología , Modelos Animales de Enfermedad , Inmunohistoquímica , Infarto de la Arteria Cerebral Media , Macrófagos/patología , Masculino , Microglía/patología , Necrosis/patología , Distribución Aleatoria , Ratas Wistar , Recurrencia , Índice de Severidad de la Enfermedad , Factores de Tiempo
17.
Stroke ; 46(3): 769-74, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25677596

RESUMEN

BACKGROUND AND PURPOSE: Minor stroke and transient ischemic attack with an intracranial occlusion are associated with neurological deterioration and disability. Tenecteplase (TNK-tissue-type plasminogen activator) compared with alteplase is easier to administer, has a longer half-life, higher fibrin specificity, possibly a lower rate of intracranial hemorrhage, and may be an ideal thrombolytic agent in this population. METHODS: TNK-Tissue-Type Plasminogen Activator Evaluation for Minor Ischemic Stroke With Proven Occlusion (TEMPO-1) was a multicenter, prospective, uncontrolled, TNK-tissue-type plasminogen activator dose-escalation, safety, and feasibility trial. Patients with a National Institutes of Health Stroke Scale ≤5 within 12 hours of symptom onset, intracranial arterial occlusion on computed tomographic angiography and absence of well-evolved infarction were eligible. Fifty patients were enrolled; 25 patients at a dose of 0.1 mg/kg, and 25 patients at 0.25 mg/kg. Primary outcome was the rate of drug-related serious adverse events. Secondary outcomes included recanalization and 90-day neurological outcome (modified Rankin Scale, 0-1). RESULTS: Median baseline National Institutes of Health Stroke Scale was 2.5 (interquartile range, 1), and median age was 71 (interquartile range, 22) years. There were no drug-related serious adverse events in tier 1. In tier 2, there was 1 symptomatic intracranial hemorrhage (4%; 95% confidence interval, 0.01-20.0). Stroke progression occurred in 6% of cases. Overall, 66% had excellent functional outcome (modified Rankin Scale, 0-1) at 90 days. Recanalization rates were high; 0.1 mg/kg (39% complete and 17% partial), 0.25 mg/kg (52% complete and 9% partial). Complete recanalization was significantly related to excellent functional outcome (modified Rankin Scale, 0-1) at 90 days (relative risk, 1.65; 95% confidence interval, 1.09-2.5; P=0.026). CONCLUSIONS: Administration of TNK-tissue-type plasminogen activator in minor stroke with intracranial occlusion is both feasible and safe. A larger randomized controlled trial is needed to prove that this treatment is efficacious. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT01654445.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Fibrinolíticos/uso terapéutico , Ataque Isquémico Transitorio/tratamiento farmacológico , Accidente Cerebrovascular/tratamiento farmacológico , Activador de Tejido Plasminógeno/uso terapéutico , Anciano , Canadá , Progresión de la Enfermedad , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Tenecteplasa , Terapia Trombolítica/métodos , Resultado del Tratamiento
18.
Can J Neurol Sci ; 41(1): 19-23, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24384332

RESUMEN

BACKGROUND: transient ischemic attack (tIA) and minor stroke have a high risk of early neurological deterioration, and patients who experience early improvement are at risk of deterioration. We generated a score for quantifying the worst reported motor and speech deficits and assessed whether this predicted outcome. METHODS: 510 tIA or minor stroke (NIHSS>4) patients were included. the Historical Stroke Severity Score (HSSS) prospectively quantified the patient's description of the worst motor or speech deficits. the HSSS was rated at the time of first assessment with more severe deficits scoring higher. Motor HSSS included assessments of arm and leg motor power (score total 0-5). Speech HSSS assessed severity of dysarthria and aphasia (total 0-3). the association between motor and speech HSSS and symptom progression was assessed during the 90-day follow-up period. RESULTS: the proportion of patients in each category of the motor HSSS was 0: 43% (216/510), 1: 22%(110/510), 2: 17% (89/510), 3: 7% (37/510), 4: 5% (28/510) and 5: 6% (30/510). Motor HSSS was associated with symptom progression (p=0.004) but not recurrent stroke. Speech HSSS was not associated with either progression or recurrent stroke. Motor HSSS predicted disability (p=0.002) and intracranial occlusion (p=0.012). Disability increased with increasing motor HSSS. CONCLUSIONS: taking a detailed history about the severity of motor deficits, but not speech, predicted outcome in tIA and minor stroke patients. A score based on the patient's description of the severity of motor symptoms predicted symptom progression, intracranial occlusion and functional outcome, but not recurrent stroke in a tIA and minor stroke population.Le Historical Stroke Severity Score moteur prédit la progression d'un accès ischémique cérébral transitoire / d'un accident vasculaire cérébral mineur.


Asunto(s)
Progresión de la Enfermedad , Ataque Isquémico Transitorio/diagnóstico , Trastornos de la Destreza Motora/diagnóstico , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/diagnóstico , Anciano , Femenino , Estudios de Seguimiento , Humanos , Ataque Isquémico Transitorio/complicaciones , Masculino , Persona de Mediana Edad , Trastornos de la Destreza Motora/etiología , Valor Predictivo de las Pruebas , Estudios Prospectivos , Accidente Cerebrovascular/complicaciones
19.
J Hematop ; 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38771403

RESUMEN

The assessment of bone marrow iron stores is typically performed on an aspirate smear slide that has been manually stained by a technologist using a commercially available kit. This approach can contribute to inconsistent results and limit the broad use of iron staining in bone marrow specimens, particularly when laboratories have low staffing and/or high specimen volumes. Here, we describe the adaptation and validation of the Ventana Benchmark automated stainer and iron stain kit for routine clinical use of staining iron in bone marrow aspirate smear slides. We assessed accuracy and precision of the Ventana automated iron staining protocol compared to the Perls Prussian blue manual iron staining index method. Hematopathologists assigned Gale scores and enumerated the percentages of erythroid sideroblasts on paired patient bone marrow aspirate smear slides stained by the automated method and the manual iron staining method. We found a similar level of performance of the Ventana automated iron stain relative to the index manual method (as assessed by Pearson correlation and Bland-Altman analyses). In addition, there was low imprecision between replicates performed via the automated iron stain protocol. We also report superior qualitative findings of the automated method in ease of localization of iron storage, visualization of sideroblasts, and counterstain consistency. Automated iron staining of bone marrow aspirate smear slides performed similarly to the manual method and may allow for accurate routine evaluation of bone marrow iron stores as part of bone marrow analysis.

20.
Int J Stroke ; : 17474930241253702, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38676572

RESUMEN

BACKGROUND: Almost half of acute ischemic stroke patients present with mild symptoms and there are large practice variations in their treatment globally. Individuals with an intracranial occlusion who present with minor stroke are at an increased risk of early neurological deterioration and poor outcomes. Individual patient data meta-analysis in the subgroup of patients with minor deficits showed benefit of alteplase in improving outcomes; however, this benefit has not been seen with intravenous alteplase in published randomized trials. DESIGN: TEMPO-2 (A Randomized Controlled Trial of Tenecteplase Versus Standard of Care for Minor Ischemic Stroke With Proven Occlusion) is a prospective, open label with blinded outcome assessment, randomized controlled trial, designed to test the superiority of intravenous tenecteplase (0.25 mg/kg) over nonthrombolytic standard of care, with an estimated sample size of 1274 patients. Adult patients presenting with acute ischemic stroke with the National Institutes of Health Stroke Scale (NIHSS) ⩽ 5 and visible arterial occlusion or perfusion deficit within 12 h of onset are randomized to receive either tenecteplase (0.25 mg/kg) or standard of care. The primary outcome is return to baseline neurological functioning, measured by the modified Rankin scale (mRS) at 90 days. Safety outcomes include death and symptomatic hemorrhage (intra or extra-cranial). Other secondary outcomes include mRS 0-1, mRS 0-2, ordinal shift analysis of the mRS, partial, and full recanalization on follow-up computed tomography angiogram. CONCLUSION: Results of this trial will aid in determining whether there is benefit of using tenecteplase (0.25 mg/kg) in treating patients presenting with minor stroke who are at high risk of developing poor outcomes due to presence of an intracranial occlusion. DATA ACCESS STATEMENT: Data will be available upon reasonable request.

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