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1.
N Engl J Med ; 390(18): 1677-1689, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38718358

RESUMO

BACKGROUND: The use of thrombectomy in patients with acute stroke and a large infarct of unrestricted size has not been well studied. METHODS: We assigned, in a 1:1 ratio, patients with proximal cerebral vessel occlusion in the anterior circulation and a large infarct (as defined by an Alberta Stroke Program Early Computed Tomographic Score of ≤5; values range from 0 to 10) detected on magnetic resonance imaging or computed tomography within 6.5 hours after symptom onset to undergo endovascular thrombectomy and receive medical care (thrombectomy group) or to receive medical care alone (control group). The primary outcome was the score on the modified Rankin scale at 90 days (scores range from 0 to 6, with higher scores indicating greater disability). The primary safety outcome was death from any cause at 90 days, and an ancillary safety outcome was symptomatic intracerebral hemorrhage. RESULTS: A total of 333 patients were assigned to either the thrombectomy group (166 patients) or the control group (167 patients); 9 were excluded from the analysis because of consent withdrawal or legal reasons. The trial was stopped early because results of similar trials favored thrombectomy. Approximately 35% of the patients received thrombolysis therapy. The median modified Rankin scale score at 90 days was 4 in the thrombectomy group and 6 in the control group (generalized odds ratio, 1.63; 95% confidence interval [CI], 1.29 to 2.06; P<0.001). Death from any cause at 90 days occurred in 36.1% of the patients in the thrombectomy group and in 55.5% of those in the control group (adjusted relative risk, 0.65; 95% CI, 0.50 to 0.84), and the percentage of patients with symptomatic intracerebral hemorrhage was 9.6% and 5.7%, respectively (adjusted relative risk, 1.73; 95% CI, 0.78 to 4.68). Eleven procedure-related complications occurred in the thrombectomy group. CONCLUSIONS: In patients with acute stroke and a large infarct of unrestricted size, thrombectomy plus medical care resulted in better functional outcomes and lower mortality than medical care alone but led to a higher incidence of symptomatic intracerebral hemorrhage. (Funded by Montpellier University Hospital; LASTE ClinicalTrials.gov number, NCT03811769.).


Assuntos
Infarto da Artéria Cerebral Anterior , Acidente Vascular Cerebral , Trombectomia , Terapia Trombolítica , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Hemorragia Cerebral/etiologia , Terapia Combinada , Procedimentos Endovasculares , Imageamento por Ressonância Magnética , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/terapia , Terapia Trombolítica/efeitos adversos , Terapia Trombolítica/métodos , Tomografia Computadorizada por Raios X , Infarto Encefálico/diagnóstico por imagem , Infarto Encefálico/etiologia , Infarto Encefálico/terapia , Doença Aguda , Artérias Cerebrais/diagnóstico por imagem , Artérias Cerebrais/cirurgia , Doenças Arteriais Cerebrais/complicações , Doenças Arteriais Cerebrais/diagnóstico por imagem , Doenças Arteriais Cerebrais/patologia , Doenças Arteriais Cerebrais/cirurgia , Infarto da Artéria Cerebral Anterior/diagnóstico por imagem , Infarto da Artéria Cerebral Anterior/patologia , Infarto da Artéria Cerebral Anterior/cirurgia
2.
Neurology ; 102(10): e209387, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38701386

RESUMO

BACKGROUND AND OBJECTIVES: Motor outcomes after stroke relate to corticospinal tract (CST) damage. The brain leverages surviving neural pathways to compensate for CST damage and mediate motor recovery. Thus, concurrent age-related damage from white matter hyperintensities (WMHs) might affect neurologic capacity for recovery after CST injury. The role of WMHs in post-stroke motor outcomes is unclear. In this study, we evaluated whether WMHs modulate the relationship between CST damage and post-stroke motor outcomes. METHODS: We used data from the multisite ENIGMA Stroke Recovery Working Group with T1 and T2/fluid-attenuated inversion recovery imaging. CST damage was indexed with weighted CST lesion load (CST-LL). WMH volumes were extracted with Freesurfer's SAMSEG. Mixed-effects beta-regression models were fit to test the impact of CST-LL, WMH volume, and their interaction on motor impairment, controlling for age, days after stroke, and stroke volume. RESULTS: A total of 223 individuals were included. WMH volume related to motor impairment above and beyond CST-LL (ß = 0.178, 95% CI 0.025-0.331, p = 0.022). Relationships varied by WMH severity (mild vs moderate-severe). In individuals with mild WMHs, motor impairment related to CST-LL (ß = 0.888, 95% CI 0.604-1.172, p < 0.001) with a CST-LL × WMH interaction (ß = -0.211, 95% CI -0.340 to -0.026, p = 0.026). In individuals with moderate-severe WMHs, motor impairment related to WMH volume (ß = 0.299, 95% CI 0.008-0.590, p = 0.044), but did not significantly relate to CST-LL or a CST-LL × WMH interaction. DISCUSSION: WMHs relate to motor outcomes after stroke and modify relationships between motor impairment and CST damage. WMH-related damage may be under-recognized in stroke research as a factor contributing to variability in motor outcomes. Our findings emphasize the importance of brain structural reserve in motor outcomes after brain injury.


Assuntos
Tratos Piramidais , Acidente Vascular Cerebral , Substância Branca , Humanos , Tratos Piramidais/diagnóstico por imagem , Tratos Piramidais/patologia , Masculino , Feminino , Idoso , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/fisiopatologia , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética , Recuperação de Função Fisiológica/fisiologia , Idoso de 80 Anos ou mais
3.
Sensors (Basel) ; 24(9)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38732992

RESUMO

In this contribution, a wearable microwave imaging system for real-time monitoring of brain stroke in the post-acute stage is described and validated. The system exploits multistatic/multifrequency (only 50 frequency samples) data collected via a low-cost and low-complexity architecture. Data are collected by an array of only 16 antennas moved by pneumatic system. Phantoms, built from ABS material and filled with appropriate Triton X-100-based mixtures to mimic the different head human tissues, are employed for the experiments. The microwave system exploits the differential scattering measures and the Incoherent MUSIC algorithm to provide a 3D image of the region under investigation. The shown results, although preliminary, confirm the potential of the proposed microwave system in providing reliable results, including for targets whose evolution is as small as 16 mL in volume.


Assuntos
Imagens de Fantasmas , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Algoritmos , Monitorização Fisiológica/métodos , Monitorização Fisiológica/instrumentação , Micro-Ondas , Dispositivos Eletrônicos Vestíveis , Imageamento Tridimensional/métodos
4.
Stroke ; 55(6): 1601-1608, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38690658

RESUMO

BACKGROUND: A coordinated network of circulating inflammatory molecules centered on the pleotropic pro-atherogenic cytokine interleukin-18 (IL-18) is linked to cerebral small vessel disease. We sought to validate the association of this inflammatory biomarker network with incident stroke risk, cognitive impairment, and imaging metrics in a sample of the Framingham Offspring Cohort. METHODS: Using available baseline measurements of serum levels of IL-18, GDF (growth and differentiation factor)-15, soluble form of receptor for advanced glycation end products, myeloperoxidase, and MCP-1 (monocyte chemoattractant protein-1) from Exam 7 of the Framingham Offspring Cohort (1998-2001), we constructed a population-normalized, equally weighted log-transformed mean Z-score value representing the average level of each serum analyte to create an inflammatory composite score (ICS5). Multivariable regression models were used to determine the association of ICS5 with incident stroke, brain magnetic resonance imaging features, and cognitive testing performance. RESULTS: We found a significant association between ICS5 score and increased risk for incident all-cause stroke (hazard ratio, 1.48 [95% CI, 1.05-2.08]; P=0.024) and ischemic stroke (hazard ratio, 1.51 [95% CI, 1.03-2.21]; P=0.033) in the Exam 7 cohort of 2201 subjects (mean age 62±9 years; 54% female) aged 45+ years with an all-cause incident stroke rate of 6.1% (135/2201) and ischemic stroke rate of 4.9% (108/2201). ICS5 and its component serum markers are all associated with the Framingham Stroke Risk Profile score (ß±SE, 0.19±0.02; P<0.0001). In addition, we found a significant inverse association of ICS5 with a global cognitive score, derived from a principal components analysis of the neuropsychological battery used in the Framingham cohort (-0.08±0.03; P=0.019). No association of ICS5 with magnetic resonance imaging metrics of cerebral small vessel disease was observed. CONCLUSIONS: Circulating serum levels of inflammatory biomarkers centered on IL-18 are associated with an increased risk of stroke and cognitive impairment in the Framingham Offspring Cohort. Linking specific inflammatory pathways to cerebral small vessel disease may enhance individualized quantitative risk assessment for future stroke and vascular cognitive impairment.


Assuntos
Biomarcadores , Inflamação , Interleucina-18 , Acidente Vascular Cerebral , Humanos , Masculino , Feminino , Biomarcadores/sangue , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/diagnóstico por imagem , Pessoa de Meia-Idade , Interleucina-18/sangue , Idoso , Inflamação/sangue , Estudos de Coortes , Incidência , Fatores de Risco , Imageamento por Ressonância Magnética , Disfunção Cognitiva/sangue , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/diagnóstico por imagem
5.
Bull Exp Biol Med ; 176(5): 649-657, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38733482

RESUMO

In translational animal study aimed at evaluation of the effectiveness of innovative methods for treating cerebral stroke, including regenerative cell technologies, of particular importance is evaluation of the dynamics of changes in the volume of the cerebral infarction in response to therapy. Among the methods for assessing the focus of infarction, MRI is the most effective and convenient tool for use in preclinical studies. This review provides a description of MR pulse sequences used to visualize cerebral ischemia at various stages of its development, and a detailed description of the MR semiotics of cerebral infarction. A comparison of various methods for morphometric analysis of the focus of a cerebral infarction, including systems based on artificial intelligence for a more objective measurement of the volume of the lesion, is also presented.


Assuntos
Imageamento por Ressonância Magnética , Imageamento por Ressonância Magnética/métodos , Animais , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/patologia , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/patologia , Modelos Animais de Doenças , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/patologia , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/patologia , Inteligência Artificial
6.
Neurology ; 102(11): e209424, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38759133

RESUMO

OBJECTIVES: A reliable method of predicting large vessel occlusion (LVO) stroke in data sets without neuroimaging could be retrospectively applied to expand research efforts. METHODS: We conducted a retrospective, cross-sectional cohort analysis of the Get With The Guidelines (GWTG)-Stroke registry. We included adult patients with a final diagnosis of ischemic stroke from 2016 to 2021 who had brain and vascular imaging and excluded those with missing data or posterior circulation stroke. RESULTS: We included 416,022 patients of which 125,381 (30.1%) had LVO. The mean age was 71 years, and 48.2% were female. The area under the receiver operating curve (AUC) for the final model, including age, sex, hypertension, dyslipidemia, atrial fibrillation, diabetes, TOAST stroke mechanism, and NIH Stroke Scale (NIHSS), was 0.79 (95% CI 0.79-0.80). Without TOAST mechanism, the AUC was 0.74. The specificity did not exceed 0.5 using different cut points for the NIHSS. DISCUSSION: We found that 30% of adult acute ischemic stroke patients in GWTG-Stroke have LVO and that the combination of clinical covariates and NIHSS is only moderately predictive of LVO status. These results are consistent with previous studies and suggest it may not be possible to retrospectively predict LVO with high accuracy in data sets without vascular neuroimaging.


Assuntos
AVC Isquêmico , Sistema de Registros , Humanos , Feminino , Masculino , Idoso , Estudos Retrospectivos , Estudos Transversais , Pessoa de Meia-Idade , AVC Isquêmico/diagnóstico por imagem , Idoso de 80 Anos ou mais , Acidente Vascular Cerebral/diagnóstico por imagem , Estudos de Coortes
7.
Phys Med ; 121: 103359, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38688073

RESUMO

PURPOSE: Strokes are severe cardiovascular and circulatory diseases with two main types: ischemic and hemorrhagic. Clinically, brain images such as computed tomography (CT) and computed tomography angiography (CTA) are widely used to recognize stroke types. However, few studies have combined imaging and clinical data to classify stroke or consider a factor as an Independent etiology. METHODS: In this work, we propose a classification model that automatically distinguishes stroke types with hypertension as an independent etiology based on brain imaging and clinical data. We first present a preprocessing workflow for head axial CT angiograms, including noise reduction and feature enhancement of the images, followed by an extraction of regions of interest. Next, we develop a multi-scale feature fusion model that combines the location information of position features and the semantic information of deep features. Furthermore, we integrate brain imaging with clinical information through a multimodal learning model to achieve more reliable results. RESULTS: Experimental results show our proposed models outperform state-of-the-art models on real imaging and clinical data, which reveals the potential of multimodal learning in brain disease diagnosis. CONCLUSION: The proposed methodologies can be extended to create AI-driven diagnostic assistance technology for categorizing strokes.


Assuntos
Angiografia por Tomografia Computadorizada , Cabeça , Hipertensão , Processamento de Imagem Assistida por Computador , Aprendizado de Máquina , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Cabeça/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Hipertensão/diagnóstico por imagem , Hipertensão/complicações , Encéfalo/diagnóstico por imagem
8.
J Stroke Cerebrovasc Dis ; 33(6): 107708, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38582265

RESUMO

INTRODUCTION: Post-stroke fatigue (PSF) has been described as early exhaustion with tiredness that develops during physical or mental activity and generally does not improve with rest. There are inconsistent findings on the relationship between the characteristics of the ischemic brain lesion and PSF. However, some studies suggest that specific neuroanatomical and neuroplastic changes could explain post-stroke fatigue. The aim was to evaluate the severity of PSF in relation to the location and the size of the ischemic lesion in acute stroke patients to establish possible predictors of PSF. PATIENTS AND METHODS: We performed a prospective observational study to establish potential early predictors of long-term PSF, which was assessed using the Fatigue Assessment Scale six months after ischemic stroke. After segmenting brain infarcts on Diffusion-Weighted Imaging (DWI) images, we studied the association with PSF using Voxel-Based Lesion-Symptom Mapping (VLSM). RESULTS: Out of 104 patients, 61 (59 %) reported PSF. Female sex and history of diabetes mellitus were associated with a greater risk of developing PSF. The association of PSF with female sex was confirmed in a replication cohort of 50 patients. The ischemic lesion volume was not associated with PSF, and VBLSM analysis did not identify any specific brain area significantly associated with PSF. CONCLUSIONS: PSF is frequent in stroke patients, especially women, even after six months. The absence of neuroanatomical correlates of PSF suggests that it is a multifactorial process with biological, psychological, and social risk factors that require further study.


Assuntos
Imagem de Difusão por Ressonância Magnética , Fadiga , AVC Isquêmico , Humanos , Feminino , Masculino , Idoso , Estudos Prospectivos , Fadiga/etiologia , Fadiga/fisiopatologia , Pessoa de Meia-Idade , Fatores de Risco , Fatores de Tempo , Fatores Sexuais , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/complicações , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Valor Preditivo dos Testes , Índice de Gravidade de Doença , Idoso de 80 Anos ou mais , Prognóstico , Medição de Risco , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem
9.
Emerg Med Pract ; 26(Suppl 4): 1-28, 2024 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-38652756

RESUMO

Acute stroke is one of the most common neurologic emergencies encountered by emergency clinicians. While point of care ultrasound has been a core part of emergency clinicians' training and practice for many years, the use of specialized ultrasound modalities in the care of acute ischemic stroke has not been as widely adopted. This review discusses the use of ultrasound in acute stroke, with a focus on applications of interest to emergency clinicians. Transcranial Doppler, carotid Doppler, microembolic signal detection, transthoracic echocardiography, evaluation for collateral circulation and optic nerve sheath diameter measurement are discussed in a case-based format, with a focus on practical applications for emergency clinicians.


Assuntos
Serviço Hospitalar de Emergência , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Ultrassonografia/métodos , Ultrassonografia Doppler Transcraniana/métodos , Sistemas Automatizados de Assistência Junto ao Leito
10.
J Neurosci ; 44(21)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38565290

RESUMO

Left-sided spatial neglect is a very common and challenging issue after right-hemispheric stroke, which strongly and negatively affects daily living behavior and recovery of stroke survivors. The mechanisms underlying recovery of spatial neglect remain controversial, particularly regarding the involvement of the intact, contralesional hemisphere, with potential contributions ranging from maladaptive to compensatory. In the present prospective, observational study, we assessed neglect severity in 54 right-hemispheric stroke patients (32 male; 22 female) at admission to and discharge from inpatient neurorehabilitation. We demonstrate that the interaction of initial neglect severity and spared white matter (dis)connectivity resulting from individual lesions (as assessed by diffusion tensor imaging, DTI) explains a significant portion of the variability of poststroke neglect recovery. In mildly impaired patients, spared structural connectivity within the lesioned hemisphere is sufficient to attain good recovery. Conversely, in patients with severe impairment, successful recovery critically depends on structural connectivity within the intact hemisphere and between hemispheres. These distinct patterns, mediated by their respective white matter connections, may help to reconcile the dichotomous perspectives regarding the role of the contralesional hemisphere as exclusively compensatory or not. Instead, they suggest a unified viewpoint wherein the contralesional hemisphere can - but must not necessarily - assume a compensatory role. This would depend on initial impairment severity and on the available, spared structural connectivity. In the future, our findings could serve as a prognostic biomarker for neglect recovery and guide patient-tailored therapeutic approaches.


Assuntos
Imagem de Tensor de Difusão , Transtornos da Percepção , Recuperação de Função Fisiológica , Acidente Vascular Cerebral , Substância Branca , Humanos , Masculino , Feminino , Transtornos da Percepção/etiologia , Transtornos da Percepção/fisiopatologia , Transtornos da Percepção/reabilitação , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/fisiopatologia , Idoso , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Pessoa de Meia-Idade , Recuperação de Função Fisiológica/fisiologia , Lateralidade Funcional/fisiologia , Estudos Prospectivos , Índice de Gravidade de Doença , Vias Neurais/fisiopatologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/patologia , Idoso de 80 Anos ou mais
11.
J Clin Neurosci ; 124: 47-53, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38643651

RESUMO

INTRODUCTION: The awareness of nonocclusive thrombus has increased with the increasing frequency of imaging methods used for acute ischemic stroke; however, the best treatment for nonocclusive thrombi is still unknown. In this study, we examined how anticoagulants affect supra-aortic artery nonocclusive thrombus and clinical outcomes. MATERIALS AND METHODS: This study included 52 patients with transient ischemic attack or stroke who were diagnosed with nonocclusive thrombi on computed tomography angiography at admission. Patients were treated with anticoagulant treatment and grouped according to treatment modality (either unfractionated heparin or low molecular weight heparin) and treatment duration. Primary safety outcome was major bleeding defined as immediate and clnically significant hemorrhage. Anticoagulant treatment was continued until the thrombus was resolved as determined by consecutive weekly computed tomography angiography controls. After thrombus resolution, treatment was directed according to the underlying etiology. Antiaggregation treatment was the preferred treatment after thrombus resolution for patients with no observed etiology. RESULTS: The affected internal carotid arteries were most frequently located in the cervical segment (48 %). Complete resolution was achieved within 2 weeks in 50 patients (96 %). The involved vasculature included the following: the extracranial carotid artery segments (n = 26, 50 %), intracranial ICA segments (n = 10, 19 %), basilar artery segments (n = 8, 15 %) and MCA segments (n = 7, 13 %). The most common underlying pathologies were atherosclerosis (n = 17), atrial fibrillation (n = 17), undetermined embolic stroke (n = 8), dissection (n = 7), and malignancy (n = 2). No symptomatic intra- or extracranial bleeding complications due to anticoagulant use were observed in any patient during the study period. A good functional outcome (modified Rankin scale score 0-2) was achieved in 49 patients (94 %) at 3 months. There was no significant difference between treatment type and duration in terms of reinfarction (p = 0.97 and p = 0.78, respectively). CONCLUSION: Anticoagulant treatment is safe and effective in symptomatic patients with intracranial or extracranial artery nonocclusive thrombus, regardless of the anticoagulant type, thrombus location and size.


Assuntos
Anticoagulantes , Ataque Isquêmico Transitório , Humanos , Masculino , Feminino , Anticoagulantes/uso terapêutico , Anticoagulantes/efeitos adversos , Idoso , Ataque Isquêmico Transitório/tratamento farmacológico , Ataque Isquêmico Transitório/complicações , Pessoa de Meia-Idade , Resultado do Tratamento , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/complicações , AVC Isquêmico/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Idoso de 80 Anos ou mais , Trombose Intracraniana/tratamento farmacológico , Trombose Intracraniana/diagnóstico por imagem , Trombose Intracraniana/complicações , Estudos Retrospectivos , Trombose/tratamento farmacológico , Trombose/diagnóstico por imagem , Heparina/uso terapêutico
12.
Neurorehabil Neural Repair ; 38(6): 425-436, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38676561

RESUMO

BACKGROUND: Corticospinal tract (CST) is the principal motor pathway; we aim to explore the structural plasticity mechanism in CST during stroke rehabilitation. METHODS: A total of 25 patients underwent diffusion tensor imaging before rehabilitation (T1), 1-month post-rehabilitation (T2), 2 months post-rehabilitation (T3), and 1-year post-discharge (T4). The CST was segmented, and fractional anisotropy (FA), axial diffusion (AD), mean diffusivity (MD), and radial diffusivity (RD) were determined using automated fiber quantification tractography. Baseline level of laterality index (LI) and motor function for correlation analysis. RESULTS: The FA values of all segments in the ipsilesional CST (IL-CST) were lower compared with normal CST. Repeated measures analysis of variance showed time-related effects on FA, AD, and MD of the IL-CST, and there were similar dynamic trends in these 3 parameters. At T1, FA, AD, and MD values of the mid-upper segments of IL-CST (around the core lesions) were the lowest; at T2 and T3, values for the mid-lower segments were lower than those at T1, while the values for the mid-upper segments gradually increased; at T4, the values for almost entire IL-CST were higher than before. The highest LI was observed at T2, with a predominance in contralesional CST. The LIs for the FA and AD at T1 were positively correlated with the change rate of motor function. CONCLUSIONS: IL-CST showed aggravation followed by improvement from around the lesion to the distal end. Balance of interhemispheric CST may be closely related to motor function, and LIs for FA and AD may have predictive value for mild-to-moderate stroke rehabilitation. Clinical Trial Registration. URL: http://www.chictr.org.cn; Unique Identifier: ChiCTR1800019474.


Assuntos
Imagem de Tensor de Difusão , Plasticidade Neuronal , Tratos Piramidais , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Tratos Piramidais/diagnóstico por imagem , Tratos Piramidais/fisiopatologia , Tratos Piramidais/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Plasticidade Neuronal/fisiologia , Reabilitação do Acidente Vascular Cerebral/métodos , Idoso , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/diagnóstico por imagem , Adulto
13.
Clin Neurol Neurosurg ; 241: 108284, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38663199

RESUMO

INTRODUCTION: It is still uncertain if higher thresholds on National Institute of Health Stroke Scale (NIHSS) are better predictors of large infarctions than the conventional 6-point cutoff. METHODS: We used 6-point and higher NIHSS thresholds including 8, 9, and 10-point to predict relative infarct areas, expressed as percentage of the affected hemisphere on axial brain computed tomography images, beginning at 5% with 5% increments each time until reaching the 40% cutoff for large infarctions, or achieving 100% sensitivity. Results were compared using area under the receiver operating characteristic curves (AUROC). RESULTS: We enrolled 151 patients of acute ischemic stroke (Mean age: 62.88 years ± 12.71; Female: 48.34%). 77 patients (50.99%) exhibited left hemisphere strokes, while 74 (49%) had right hemisphere involvement. Sensitivity values of the 6-point for infarcts measuring 5%, 10%, 20%, 30%, and 40% were 62%, 64%, 77%, 82%, and 100%, respectively. At 40% infarct-size, 8-point achieved comparable results (52%, 55%, 69%, 76%, 100%), closely aligning with the 9-point (50%, 53%, 69%, 76%, 100%). The10-point was slightly trailing behind in sensitivity at 40% infarct-core (96%). Moreover, higher thresholds exhibited improved false-positive rates (FPR). At 40% infarct size, the FPRs of 6, 8, 9, and 10 points were 39%, 27%, 27%, and 21% respectively. Higher thresholds had augmented AUROC values (0.86, 0.86, 0.89) as compared to the 6-point (0.80). Logistic regression identified 14-point as definitive cutoff for large infarctions. CONCLUSION: Higher thresholds can better differentiate small and medium infarcts as true-negatives and substantially reduce false-positive referrals for mechanical thrombectomy.


Assuntos
AVC Isquêmico , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Reprodutibilidade dos Testes , AVC Isquêmico/diagnóstico por imagem , Índice de Gravidade de Doença , Acidente Vascular Cerebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X , National Institutes of Health (U.S.) , Sensibilidade e Especificidade , Idoso de 80 Anos ou mais
14.
BMC Neurol ; 24(1): 119, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605286

RESUMO

BACKGROUND: Ischemic stroke in young adults can be caused by a variety of etiologies including the monogenic disorders. Visceral heterotaxy is a condition caused by abnormal left-right determinations during embryonic development. We aimed to determine the cause of a young ischemic stroke patient with visceral heterotaxy. CASE PRESENTATION: We performed neurological, radiological, and genetic evaluations in a 17-year-old male patient presenting ischemic stroke and visceral heterotaxy to determine the underlying cause of this rare disease combination. Brain magnetic resonance imaging (MRI) showed evidence of embolic stroke, abdominal computed tomography (CT) showed visceral heterotaxy, and echocardiogram showed cardiac anomaly with right-to-left-shunt (RLS). Whole genome sequencing (WGS) revealed a heterozygous missense variant (NM_018055.5: c.1016 T > C, p.(Met339Val)) in the NODAL gene, which is essential to the determination of the left-right body axis. CONCLUSIONS: Our study highlights the importance of evaluating genetic etiology in young ischemic stroke and the need for stroke risk management in visceral heterotaxy patients with RLS. To the best of our knowledge, we report the first genetically-confirmed case of visceral heterotaxy with young embolic stroke reported to date.


Assuntos
AVC Embólico , Síndrome de Heterotaxia , Adolescente , Humanos , Masculino , Anormalidades Cardiovasculares , Síndrome de Heterotaxia/genética , Imageamento por Ressonância Magnética , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/genética
15.
Comput Biol Med ; 174: 108326, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38599066

RESUMO

Accurate and expeditious segmentation of stroke lesions can greatly assist physicians in making accurate medical diagnoses and administering timely treatments. However, there are two limitations to the current deep learning methods. On the one hand, the attention structure utilizes only local features, which misleads the subsequent segmentation; on the other hand, simple downsampling compromises task-relevant detailed semantic information. To address these challenges, we propose a novel feature refinement and protection network (FRPNet) for stroke lesion segmentation. FRPNet employs a symmetric encoding-decoding structure and incorporates twin attention gate (TAG) and multi-dimension attention pooling (MAP) modules. The TAG module leverages the self-attention mechanism and bi-directional attention to extract both global and local features of the lesion. On the other hand, the MAP module establishes multidimensional pooling attention to effectively mitigate the loss of features during the encoding process. Extensive comparative experiments show that, our method significantly outperforms the state-of-the-art approaches with 60.16% DSC, 36.20px HD and 85.72% DSC, 27.02px HD on two ischemic stroke datasets that contain all stroke stages and several sequences of stroke images. The excellent results that exceed those of existing methods illustrate the efficacy and generalizability of the proposed method. The source code is released on https://github.com/wu2ze2lin2/FRPNet.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Acidente Vascular Cerebral , Humanos , Imageamento por Ressonância Magnética/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Aprendizado Profundo , Interpretação de Imagem Assistida por Computador/métodos , Algoritmos
16.
Radiology ; 311(1): e231934, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38652031

RESUMO

Cryptogenic stroke refers to a stroke of undetermined etiology. It accounts for approximately one-fifth of ischemic strokes and has a higher prevalence in younger patients. Embolic stroke of undetermined source (ESUS) refers to a subgroup of patients with nonlacunar cryptogenic strokes in whom embolism is the suspected stroke mechanism. Under the classifications of cryptogenic stroke or ESUS, there is wide heterogeneity in possible stroke mechanisms. In the absence of a confirmed stroke etiology, there is no established treatment for secondary prevention of stroke in patients experiencing cryptogenic stroke or ESUS, despite several clinical trials, leaving physicians with a clinical dilemma. Both conventional and advanced MRI techniques are available in clinical practice to identify differentiating features and stroke patterns and to determine or infer the underlying etiologic cause, such as atherosclerotic plaques and cardiogenic or paradoxical embolism due to occult pelvic venous thrombi. The aim of this review is to highlight the diagnostic utility of various MRI techniques in patients with cryptogenic stroke or ESUS. Future trends in technological advancement for promoting the adoption of MRI in such a special clinical application are also discussed.


Assuntos
AVC Embólico , Imageamento por Ressonância Magnética , Humanos , AVC Embólico/diagnóstico por imagem , AVC Embólico/etiologia , Imageamento por Ressonância Magnética/métodos , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/etiologia , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia
17.
Comput Biol Med ; 175: 108509, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38677171

RESUMO

This paper provides a comprehensive review of deep learning models for ischemic stroke lesion segmentation in medical images. Ischemic stroke is a severe neurological disease and a leading cause of death and disability worldwide. Accurate segmentation of stroke lesions in medical images such as MRI and CT scans is crucial for diagnosis, treatment planning and prognosis. This paper first introduces common imaging modalities used for stroke diagnosis, discussing their capabilities in imaging lesions at different disease stages from the acute to chronic stage. It then reviews three major public benchmark datasets for evaluating stroke segmentation algorithms: ATLAS, ISLES and AISD, highlighting their key characteristics. The paper proceeds to provide an overview of foundational deep learning architectures for medical image segmentation, including CNN-based and transformer-based models. It summarizes recent innovations in adapting these architectures to the task of stroke lesion segmentation across the three datasets, analyzing their motivations, modifications and results. A survey of loss functions and data augmentations employed for this task is also included. The paper discusses various aspects related to stroke segmentation tasks, including prior knowledge, small lesions, and multimodal fusion, and then concludes by outlining promising future research directions. Overall, this comprehensive review covers critical technical developments in the field to support continued progress in automated stroke lesion segmentation.


Assuntos
Aprendizado Profundo , AVC Isquêmico , Humanos , AVC Isquêmico/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Processamento de Imagem Assistida por Computador/métodos , Interpretação de Imagem Assistida por Computador/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Algoritmos
18.
BMJ Case Rep ; 17(4)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589243

RESUMO

A previously healthy man in his 60s presents with a one-day history of insidious onset headache and 'walking into doors'. He reported transient right arm pain and tingling but no weakness. A CT brain showed a right middle cerebral artery (MCA) infarct as well as a synchronous right frontal lobe convexal subarachnoid haemorrhage (cSAH). An arch to vertex CT angiogram demonstrated right MCA occlusion and complete right internal carotid artery (ICA) occlusion from its origin. Reconstitution of flow was seen within the distal right ICA at the level of the distal foramen lacerum. A repeat CT of the brain after one week showed a stable appearance of the bleeding and infarct. He was commenced on antiplatelet therapy for the treatment of the ischaemic stroke as well as secondary prevention.This is a rare case of synchronous right MCA infarct as well as a right frontal cSAH secondary to ipsilateral carotid artery occlusion.


Assuntos
Isquemia Encefálica , Doenças das Artérias Carótidas , AVC Isquêmico , Acidente Vascular Cerebral , Hemorragia Subaracnóidea , Humanos , Masculino , Artéria Carótida Interna/diagnóstico por imagem , Infarto da Artéria Cerebral Média , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/etiologia , Pessoa de Meia-Idade , Idoso
20.
Neurorehabil Neural Repair ; 38(6): 447-459, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38602161

RESUMO

BACKGROUND: The prediction of post-stroke language function is essential for the development of individualized treatment plans based on the personal recovery potential of aphasic stroke patients. OBJECTIVE: To establish a framework for integrating information on connectivity disruption of the language network based on routinely collected clinical magnetic resonance (MR) images into Random Forest modeling to predict post-stroke language function. METHODS: Language function was assessed in 76 stroke patients from the Non-Invasive Repeated Therapeutic Stimulation for Aphasia Recovery trial, using the Token Test (TT), Boston Naming Test (BNT), and Semantic Verbal Fluency (sVF) Test as primary outcome measures. Individual infarct masks were superimposed onto a diffusion tensor imaging tractogram reference set to calculate Change in Connectivity scores of language-relevant gray matter regions as estimates of structural connectivity disruption. Multivariable Random Forest models were derived to predict language function. RESULTS: Random Forest models explained moderate to high amount of variance at baseline and follow-up for the TT (62.7% and 76.2%), BNT (47.0% and 84.3%), and sVF (52.2% and 61.1%). Initial language function and non-verbal cognitive ability were the most important variables to predict language function. Connectivity disruption explained additional variance, resulting in a prediction error increase of up to 12.8% with variable omission. Left middle temporal gyrus (12.8%) and supramarginal gyrus (9.8%) were identified as among the most important network nodes. CONCLUSION: Connectivity disruption of the language network adds predictive value beyond lesion volume, initial language function, and non-verbal cognitive ability. Obtaining information on connectivity disruption based on routine clinical MR images constitutes a significant advancement toward practical clinical application.


Assuntos
Afasia , Imagem de Tensor de Difusão , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/fisiopatologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Afasia/etiologia , Afasia/reabilitação , Afasia/fisiopatologia , Afasia/diagnóstico por imagem , Imageamento por Ressonância Magnética , Adulto , Idioma
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