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1.
Comput Intell Neurosci ; 2021: 7552185, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34504522

RESUMO

For the segmentation task of stroke lesions, using the attention U-Net model based on the self-attention mechanism can suppress irrelevant regions in an input image while highlighting salient features useful for specific tasks. However, when the lesion is small and the lesion contour is blurred, attention U-Net may generate wrong attention coefficient maps, leading to incorrect segmentation results. To cope with this issue, we propose a dual-path attention compensation U-Net (DPAC-UNet) network, which consists of a primary network and auxiliary path network. Both networks are attention U-Net models and identical in structure. The primary path network is the core network that performs accurate lesion segmentation and outputting of the final segmentation result. The auxiliary path network generates auxiliary attention compensation coefficients and sends them to the primary path network to compensate for and correct possible attention coefficient errors. To realize the compensation mechanism of DPAC-UNet, we propose a weighted binary cross-entropy Tversky (WBCE-Tversky) loss to train the primary path network to achieve accurate segmentation and propose another compound loss function called tolerance loss to train the auxiliary path network to generate auxiliary compensation attention coefficient maps with expanded coverage area to perform compensate operations. We conducted segmentation experiments using the 239 MRI scans of the anatomical tracings of lesions after stroke (ATLAS) dataset to evaluate the performance and effectiveness of our method. The experimental results show that the DSC score of the proposed DPAC-UNet network is 6% higher than the single-path attention U-Net. It is also higher than the existing segmentation methods of the related literature. Therefore, our method demonstrates powerful abilities in the application of stroke lesion segmentation.


Assuntos
Processamento de Imagem Assistida por Computador , Acidente Vascular Cerebral , Humanos , Imageamento por Ressonância Magnética , Acidente Vascular Cerebral/diagnóstico por imagem
2.
Zhen Ci Yan Jiu ; 46(7): 610-5, 2021 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-34369683

RESUMO

OBJECTIVE: To observe the effect of tiaoren tongdu acupuncture method (for regulating the function of the Conception Vessel and promoting the circulation of the Governor Vessel) on fractional anisotropy (FA) and upper-extremity motor function after cerebral infarction by diffusion densor imaging (DTI) technology. METHODS: The patients with cerebral infarction were divided into an acupuncture group and a control group according to the random number table method, 27 cases in each group. In the control group, the basic treatment with conventional medication was used. In the acupuncture group, on the basic treatment as the control group, the tiaoren tongdu acupuncture method was provided. Main acupoints included Baihui (GV20), Shuigou(GV26), Chengjiang(CV24), Guanyuan(CV4), Qihai (CV6), Zhongwan (CV12), Shenting(GV24) and Mingmen(GV4). Supplementary points included Jianyu(LI15), Chize(LU5), Houxi (SI3), Weizhong (BL40), Zusanli (ST36) and Taichong (LR3) on the affected side. The needles were retained for 30 min. Acupuncture was given once a day, at the interval of 1 days every week, consecutively for 4 weeks. The upper extremity Fugl-Meyer assessment (UE-FMA) was used to evaluate the motor function of upper extremity before and after treatment. DTI was adopted to observe the FA values of infarct focus, posterior limb of internal capsule (PLIC) and cerebral peduncle on the affected side, as well as FA values at the corresponding parts on the healthy side in the patients of two groups. The relative differences (rFA) were calculated. RESULTS: Compared with their own pretreatment, the UE-FMA value was significantly higher after treatment in either of two groups separately (P<0.05 in the control group, P<0.01 in the acupuncture group). The difference of UE-FMA before and after treatment in the acupuncture group was larger than that in the control group (P<0.05). The FA and rFA values in infarct focus were higher than those before treatment in the two groups (P<0.05). The FA and rFA differences before and after treatment in the infarct focus and PLIC on the affected side were higher in the acupuncture group as compared with the control group (P<0.05). The UE-FMA difference was positively correlated with the rFA difference of each part in either group (P<0.05), and the correlation was the strongest in PLIC on the affected side in either group (P<0.01). CONCLUSION: Tiaoren tongdu acupuncture significantly improves the upper limb movement function after cerebral infarction. The rFA value of PLIC combined with UE-FMA can be used to evaluate the therapeutic effect of acupuncture on the upper extremity movement after cerebral infarction.


Assuntos
Terapia por Acupuntura , Acidente Vascular Cerebral , Pontos de Acupuntura , Anisotropia , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/terapia , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia , Resultado do Tratamento , Extremidade Superior
3.
Rev Soc Bras Med Trop ; 54: e03012021, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34431948

RESUMO

Neurological manifestations add prognostic severity to the coronavirus disease (COVID-19). Here, we report a case of a pregnant patient with COVID-19 that progressed with neurological complications. Magnetic resonance imaging revealed cerebral ischemic insults associated with cortical laminar necrosis, in addition to an intraparenchymal brain hematoma. The mechanisms of vascular injury may have multifactorial origins and result in complex radiological presentations. Since stroke associated with pregnancy is one of the main causes of long-term disability in women, accurate identification of cerebrovascular events may potentially reduce sequelae.


Assuntos
COVID-19 , Acidente Vascular Cerebral , Feminino , Humanos , Imageamento por Ressonância Magnética , Gravidez , Prognóstico , SARS-CoV-2 , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia
4.
AMIA Annu Symp Proc ; 2021: 170-179, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34457131

RESUMO

Classifying fine-grained ischemic stroke phenotypes relies on identifying important clinical information. Radiology reports provide relevant information with context to determine such phenotype information. We focus on stroke phenotypes with location-specific information: brain region affected, laterality, stroke stage, and lacunarity. We use an existing fine-grained spatial information extraction system-Rad-SpatialNet-to identify clinically important information and apply simple domain rules on the extracted information to classify phenotypes. The performance of our proposed approach is promising (recall of 89.62% for classifying brain region and 74.11% for classifying brain region, side, and stroke stage together). Our work demonstrates that an information extraction system based on a fine-grained schema can be utilized to determine complex phenotypes with the inclusion of simple domain rules. These phenotypes have the potential to facilitate stroke research focusing on post-stroke outcome and treatment planning based on the stroke location.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Radiologia , Acidente Vascular Cerebral , Isquemia Encefálica/diagnóstico por imagem , Humanos , Armazenamento e Recuperação da Informação , Acidente Vascular Cerebral/diagnóstico por imagem
5.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 38(4): 790-796, 2021 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-34459180

RESUMO

Clinically, non-contrastive computed tomography (NCCT) is used to quickly diagnose the type and area of ​​stroke, and the Alberta stroke program early computer tomography score (ASPECTS) is used to guide the next treatment. However, in the early stage of acute ischemic stroke (AIS), it's difficult to distinguish the mild cerebral infarction on NCCT with the naked eye, and there is no obvious boundary between brain regions, which makes clinical ASPECTS difficult to conduct. The method based on machine learning and deep learning can help physicians quickly and accurately identify cerebral infarction areas, segment brain areas, and operate ASPECTS quantitative scoring, which is of great significance for improving the inconsistency in clinical ASPECTS. This article describes current challenges in the field of AIS ASPECTS, and then summarizes the application of computer-aided technology in ASPECTS from two aspects including machine learning and deep learning. Finally, this article summarizes and prospects the research direction of AIS-assisted assessment, and proposes that the computer-aided system based on multi-modal images is of great value to improve the comprehensiveness and accuracy of AIS assessment, which has the potential to open up a new research field for AIS-assisted assessment.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Alberta , Isquemia Encefálica/diagnóstico por imagem , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X
6.
PLoS One ; 16(8): e0256116, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34383840

RESUMO

INTRODUCTION: The coronavirus disease (COVID-19) pandemic has delayed the management of other serious medical conditions. This study presents an efficient method to prevent the degradation of the quality of diagnosis and treatment of other critical diseases during the pandemic. METHODS: We performed a retrospective observational study. The primary outcome was ED length of stay (ED LOS). The secondary outcomes were the door-to-balloon time in patients with suspected ST-segment elevation myocardial infarction and door-to-brain computed tomography time for patients with suspected stroke. The outcome measures were compared between patients who were treated in the red and orange zones designated as the changeable isolation unit and those who were treated in the non-isolation care unit. To control confounding factors, we performed propensity score matching, following which, outcomes were analyzed for non-inferiority. RESULTS: The mean ED LOS for hospitalized patients in the isolation and non-isolation care units were 406.5 min (standard deviation [SD], 237.9) and 360.2 min (SD, 226.4), respectively. The mean difference between the groups indicated non-inferiority of the isolation care unit (p = 0.037) but not in the patients discharged from the ED (p>0.999). The mean difference in the ED LOS for patients admitted to the ICU between the isolation and non-isolation care units was -22.0 min (p = 0.009). The mean difference in the door-to-brain computed tomography time between patients with suspected stroke in the isolation and non-isolation care units was 7.4 min for those with confirmed stroke (p = 0.013), and -20.1 min for those who were discharged (p = 0.012). The mean difference in the door-to-balloon time between patients who underwent coronary angiography in the isolation and non-isolation care units was -2.1 min (p<0.001). CONCLUSIONS: Appropriate and efficient handling of a properly planned ED plays a key role in improving the quality of medical care for other critical diseases during the COVID-19 outbreak.


Assuntos
COVID-19 , Serviço Hospitalar de Emergência/organização & administração , Tempo de Internação , Infarto do Miocárdio/diagnóstico , Acidente Vascular Cerebral/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Surtos de Doenças , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/terapia , Estudos Retrospectivos , Acidente Vascular Cerebral/terapia
7.
Neuroimage Clin ; 31: 102774, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34371239

RESUMO

BACKGROUND: The complex crossing-fiber characteristics in the dual-stream system have been ignored by traditional diffusion tensor models regarding disconnections in post-stroke aphasia. It is valuable to identify microstructural damage of crossing-fiber pathways and reveal accurate fiber-specific language mapping in patients with aphasia. METHODS: This cross-sectional study collected magnetic resonance imaging data from 29 participants with post-stroke aphasia in the subacute stage and from 33 age- and sex-matched healthy controls. Fixel-based analysis was performed to examine microstructural fiber density (FD) and bundle cross-section alterations of specific fiber populations in crossing-fiber regions. Group comparisons were performed, and relationships with language scores were assessed. RESULTS: The aphasic group exhibited significant fixel-wise FD reductions in the dual-stream tracts, including the left inferior fronto-occipital fasciculus (IFOF), arcuate fasciculus, and superior longitudinal fasciculus (SLF) III (family-wise-error-corrected p < 0.05). Voxel- and fixel-wise comparisons revealed mismatched distributions in regions with crossing-fiber nexuses. Fixel-wise correlation analyses revealed significant associations between comprehension impairment and reduced FD in the temporal and frontal segments of the left IFOF, and also mapped naming ability to the IFOF. Average features along the whole course of dominant tracts assessed with tract-wise analyses attributed word-level comprehension to the IFOF (r = 0.723, p < 0.001) and revealed a trend-level correlation between sentence-level comprehension and FD of the SLF III (r = 0.451, p = 0.021). The mean FD of the uncinate fasciculus (UF) and IFOF correlated with total and picture naming scores, and the IFOF also correlated with responsive naming subdomains (Bonferroni corrected p < 0.05). CONCLUSIONS: FD reductions of dual streams suggest that intra-axonal volume reduction constitutes the microstructural damage of white matter integrity in post-stroke aphasia. Fixel-based analysis provides a complementary method of language mapping that identifies fiber-specific tracts in the left hemisphere language network with greater specificity than voxel-based analysis. It precisely locates the precise segments of the IFOF for comprehension, yields fiber-specific evidence for the debated UF-naming association, and reveals dissociative subdomain associations with distinct tracts.


Assuntos
Afasia , Acidente Vascular Cerebral , Substância Branca , Afasia/diagnóstico por imagem , Afasia/etiologia , Estudos Transversais , Imagem de Tensor de Difusão , Humanos , Idioma , Vias Neurais/diagnóstico por imagem , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
8.
Neuropsychologia ; 160: 107980, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34352268

RESUMO

BACKGROUND AND PURPOSE: Subcortical ischemic stroke usually leads to the geometric microstructural changes in the orientation of peri-infarct white matter fiber. We conducted the study to determine the microstructural changes in the white matter fiber orientation in post stroke patients with and without cognitive impairment (PSCI, NPSCI), and to investigate the impact of peri-infarct white matter damage on the morphology and functional connectivity of their projective cerebral regions. METHODS: A novel mathematical framework called Director Field Analysis (DFA) was applied to study the microstructural changes in the orientation of white matter fiber in PSCI (n = 23), NPSCI (n = 17), and cognitively normal (CN, n = 29) individuals. RESULTS: PSCI patients had extensive abnormalities in the orientation of white matter fiber in the corpus callosum, bilateral internal capsule, external capsule, forceps major, forceps minor, and corticospinal tract in comparison with NPSCI and CN. NPSCI patients also showed significant increases in bend and twist of white matter fiber orientation in the internal capsule in comparison with CN. Seed-based functional connectivity analysis showed that peri-infarct white matter deficits indicate a significant impact on functional connectivity with related cortical regions, suggesting the coexistence of impairment and compensation in post-stroke. In addition, these peri-infarct white matter damages and abnormal functional connectivity were significantly correlated with cognitive scores. Machine learning model also indicated that these changes in white matter fiber orientation and functional connectivity can predict the cognitive status in post-stroke. CONCLUSIONS: Post-stroke patients experienced pathological damage in the orientation of peri-infarct white matter fiber. The peri-infarct white matter damage may further induce the abnormal functional connectivity in projective cerebral regions. These degenerations of peri-infarct white matter fiber and associated functional connectivity changes may mediate the cognitive impairment in post-stroke.


Assuntos
Disfunção Cognitiva , Acidente Vascular Cerebral , Substância Branca , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Corpo Caloso/diagnóstico por imagem , Humanos , Tratos Piramidais , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
9.
J Headache Pain ; 22(1): 93, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34384351

RESUMO

BACKGROUND: We report the first case of a patient who suffered transient focal neurological deficit mimicking stroke following CoronaVac vaccination. However, instead of an ischemic stroke, motor aura was suspected. CASE PRESENTATIONS: A 24 year-old Thai female presented with left hemiparesis fifteen minutes after receiving CoronaVac. She also had numbness of her left arm and legs, flashing lights, and headaches. On physical examination, her BMI was 32.8. Her vital signs were normal. She had moderate left hemiparesis (MRC grade III), numbness on her left face, arms, and legs. Her weakness continued for 5 days. A brain CT scan was done showing no evidence of acute infarction. Acute treatment with aspirin was given. MRI in conjunction with MRA was performed in which no restricted diffusion was seen. A SPECT was performed to evaluate the function of the brain showing significant hypoperfusion of the right hemisphere. The patient gradually improved and was discharged. DISCUSSIONS: In this study, we present the first case of stroke mimic after CoronaVac vaccination. After negative imaging studies had been performed repeatedly, we reach a conclusion that stroke is unlikely to be the cause. Presumably, this phenomenon could possibly have abnormal functional imaging study. Therefore, we believed that it might be due to cortical spreading depression, like migraine aura, which we had conducted a literature review.


Assuntos
Isquemia Encefálica , COVID-19 , Epilepsia , AVC Isquêmico , Enxaqueca com Aura , Acidente Vascular Cerebral , Adulto , Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico por imagem , Feminino , Humanos , SARS-CoV-2 , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Vacinação , Adulto Jovem
10.
Artigo em Inglês | MEDLINE | ID: mdl-34360349

RESUMO

This paper presents a scientific foundation for automated stroke severity classification. We have constructed and assessed a system which extracts diagnostically relevant information from Magnetic Resonance Imaging (MRI) images. The design was based on 267 images that show the brain from individual subjects after stroke. They were labeled as either Lacunar Syndrome (LACS), Partial Anterior Circulation Syndrome (PACS), or Total Anterior Circulation Stroke (TACS). The labels indicate different physiological processes which manifest themselves in distinct image texture. The processing system was tasked with extracting texture information that could be used to classify a brain MRI image from a stroke survivor into either LACS, PACS, or TACS. We analyzed 6475 features that were obtained with Gray-Level Run Length Matrix (GLRLM), Higher Order Spectra (HOS), as well as a combination of Discrete Wavelet Transform (DWT) and Gray-Level Co-occurrence Matrix (GLCM) methods. The resulting features were ranked based on the p-value extracted with the Analysis Of Variance (ANOVA) algorithm. The ranked features were used to train and test four types of Support Vector Machine (SVM) classification algorithms according to the rules of 10-fold cross-validation. We found that SVM with Radial Basis Function (RBF) kernel achieves: Accuracy (ACC) = 93.62%, Specificity (SPE) = 95.91%, Sensitivity (SEN) = 92.44%, and Dice-score = 0.95. These results indicate that computer aided stroke severity diagnosis support is possible. Such systems might lead to progress in stroke diagnosis by enabling healthcare professionals to improve diagnosis and management of stroke patients with the same resources.


Assuntos
Imageamento por Ressonância Magnética , Acidente Vascular Cerebral , Algoritmos , Diagnóstico por Computador , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Máquina de Vetores de Suporte
11.
Zhonghua Yi Xue Za Zhi ; 101(29): 2333-2336, 2021 Aug 03.
Artigo em Chinês | MEDLINE | ID: mdl-34333951

RESUMO

Data of 189 patients with first-ever cardioembolic stroke (CES) hospitalized in the Second People's Hospital of Changzhou from June 2014 to September 2019 were retrospectively analyzed. The neuoimaging markers of chronic small vessel disease (cSVDm) were evaluated and their total burden (0-3 points) was calculated. At 90 d after onset, 65 patients had poor prognosis. Regression analysis showed that the total cSVDm burden score was an independent riskfactor for the poor prognosis(OR=1.754, 95%CI:1.137-2.707, P=0.011).


Assuntos
Doenças de Pequenos Vasos Cerebrais , AVC Embólico , Acidente Vascular Cerebral , Humanos , Imageamento por Ressonância Magnética , Neuroimagem , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico por imagem
12.
BMC Neurol ; 21(1): 320, 2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404371

RESUMO

BACKGROUND: The cerebellum receives afferent signals from spinocerebellar pathways regulating lower limb movements. However, the longitudinal changes in the spinocerebellar pathway in the early stage of unilateral supratentorial stroke and their potential clinical significance have received little attention. METHODS: Diffusion tensor imaging and Fugl-Meyer assessment of lower limb were performed 1, 4, and 12 weeks after onset in 33 patients with acute subcortical infarction involving the supratentorial areas, and in 33 healthy subjects. We evaluated group differences in diffusion metrics in the bilateral inferior cerebellar peduncle (ICP) and analyzed the correlation between ICP diffusion metrics and changes to the Fugl-Meyer scores of the affected lower limb within 12 weeks after stroke. RESULTS: Significantly decreased fractional anisotropy and increased mean diffusivity were found in the contralesional ICP at week 12 after stroke compared to controls (all P < 0.01) and those at week 1 (all P < 0.05). There were significant fractional anisotropy decreases in the ipsilesional ICP at week 4 (P = 0.008) and week 12 (P = 0.004) compared to controls. Both fractional anisotropy (rs = 0.416, P = 0.025) and mean diffusivity (rs = -0.507, P = 0.005) changes in the contralesional ICP correlated with changes in Fugl-Meyer scores of the affected lower limb in all patients. CONCLUSIONS: Bilateral ICP degeneration occurs in the early phase of supratentorial stroke, and diffusion metric values of the contralesional ICP are useful indicators of affected lower limb function after supratentorial stroke.


Assuntos
Cerebelo/diagnóstico por imagem , Infarto Cerebral/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Extremidade Inferior/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica
13.
J Med Case Rep ; 15(1): 346, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34261516

RESUMO

BACKGROUND: Klüver-Bucy syndrome is a rare and complex neurobehavioral cluster that occurs in humans and results from a temporal lobe lesion. It can be associated with a variety of causes. Stroke is a rarely reported cause of this syndrome. CASE PRESENTATION: In this report, we present the case of a 68-year-old Saudi male who developed Klüver-Bucy syndrome subsequent to a nondominant middle cerebral artery ischemic stroke involving right temporal lobe. The patient manifested most of the Klüver-Bucy syndrome clinical features, including hypersexuality, hyperphagia, hyperorality, and visual hypermetamorphosis (excessive tendency to react to every visual stimulation with a tendency to touch every such stimulus). These neurobehavioral manifestations improved after he was started on treatment. CONCLUSIONS: The clinical course, anatomical association relying on pathophysiology, and potential treatment have all been deliberated in regard to the rare occurrence of Klüver-Bucy syndrome resulting from temporal lobe pathology.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Síndrome de Kluver-Bucy , Acidente Vascular Cerebral , Idoso , Humanos , Síndrome de Kluver-Bucy/etiologia , Masculino , Artéria Cerebral Média , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia
14.
Neuroimage Clin ; 31: 102744, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34245995

RESUMO

Current thrombolysis for acute ischemic stroke (AIS) treatment strictly relies on the time since stroke (TSS) less than 4.5 h. However, some patients are excluded from thrombolytic treatment because of the unknown TSS. The diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) mismatch can simply identify TSS since lesion intensities are not identical at different onset time. In this paper, we propose an automatic machine learning method to classify the TSS less than or more than 4.5 h. First, we develop a cross-modal convolutional neural network to accurately segment the stroke lesions from DWI and FLAIR images. Second, the features are extracted from DWI and FLAIR according to the segmentation regions of interest (ROI). Finally, the features are fed to machine learning models to identify TSS. In DWI and FLAIR ROI segmentation, the networks obtain high Dice coefficients with 0.803 and 0.647. The classification test results show that our model achieves an accuracy of 0.805, with a sensitivity of 0.769 and a specificity of 0.840. Our approach outperforms human reading DWI-FLAIR mismatch model, illustrating the potential for automatic and fast TSS identification.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Humanos , Aprendizado de Máquina , Acidente Vascular Cerebral/diagnóstico por imagem , Fatores de Tempo
15.
Cortex ; 142: 104-121, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34265734

RESUMO

OBJECTIVE: This study investigates the clinical course of recovery of apraxia after left-hemisphere stroke and the underlying neuroanatomical correlates for persisting or recovering deficits in relation to the major processing streams in the network for motor cognition. METHODS: 90 patients were examined during the acute (4.74 ± 2.73 days) and chronic (14.3 ± 15.39 months) stage after left-hemisphere stroke for deficits in meaningless imitation, as well as production and conceptual errors in tool use pantomime. Lesion correlates for persisting or recovering deficits were analyzed with an extension of the non-parametric Brunner-Munzel rank-order test for multi-factorial designs (two-way repeated-measures ANOVA) using acute images. RESULTS: Meaningless imitation and tool use production deficits persisted into the chronic stage. Conceptual errors in tool use pantomime showed an almost complete recovery. Imitation errors persisted after occipitotemporal and superior temporal lesions in the dorso-dorsal stream. Chronic pantomime production errors were related to the supramarginal gyrus, the key structure of the ventro-dorsal stream. More anterior lesions in the ventro-dorsal stream (ventral premotor cortex) were additionally associated with poor recovery of production errors in pantomime. Conceptual errors in pantomime after temporal and supramarginal gyrus lesions persisted into the chronic stage. However, they resolved completely when related to angular gyrus or insular lesions. CONCLUSION: The diverging courses of recovery in different apraxia tasks can be related to different mechanisms. Critical lesions to key structures of the network or entrance areas of the processing streams lead to persisting deficits in the corresponding tasks. Contrary, lesions located outside the core network but inducing a temporary network dysfunction allow good recovery e.g., of conceptual errors in pantomime. The identification of lesion correlates for different long-term recovery patterns in apraxia might also allow early clinical prediction of the course of recovery.


Assuntos
Apraxias , Acidente Vascular Cerebral , Apraxias/diagnóstico por imagem , Apraxias/etiologia , Humanos , Comportamento Imitativo , Imageamento por Ressonância Magnética , Lobo Parietal , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem
16.
Eur J Radiol ; 142: 109846, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34247031

RESUMO

Acute ischaemic stroke (AIS) in children is generally considered an up-to-date and controversial topic because its presents significant peculiarities. Focal cerebral arteriopathies (FCA) are a possible cause of AIS in children characterized by an unilateral lesion of the terminal internal cerebral artery (ICA) and proximal segment (M1) of middle cerebral artery (MCA), leading to subocclusion, occasionally with a typical "striate" pattern and a tendency to stability or regression at follow-up. It is unclear whether in FCA the basic lesion is an inflammatory or a dissective arterial pathology. Herein we report a small series of children (<16 yo) with AIS from a FCA who underwent mechanical thrombectomy (MT). We speculate on the angiographic findings suggesting an aetiology of the lesion, and on indications and limits of the currently available treatments.


Assuntos
Isquemia Encefálica , Doenças Arteriais Cerebrais , Transtornos Cerebrovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/diagnóstico por imagem , Doenças Arteriais Cerebrais/diagnóstico por imagem , Doenças Arteriais Cerebrais/terapia , Criança , Humanos , Artéria Cerebral Média , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia , Trombectomia , Resultado do Tratamento
17.
Eur J Radiol ; 142: 109862, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34298390

RESUMO

PURPOSE: To evaluate atherosclerotic plaque prevalence and characteristics between left and right cervicocephalic arteries and between anterior and posterior circulation stroke (ACS and PCS). METHODS: This retrospective study included 284 patients with acute ischemic stroke (199 ACS and 85 PCS) involving large-artery atherosclerosis or small-artery occlusion. We assessed atherosclerotic plaque prevalence and characteristics (plaque type, plaque surface morphology, plaque distribution, location of calcified nodules and plaque thickness) in each segment and their comparisons between left and right arteries and between ACS and PCS. RESULTS: The left subclavian artery (L-SA), common carotid artery (L-CCA) and intracranial vertebral artery (L-IVA) had significantly higher prevalence of atherosclerotic plaque than the right (R) corresponding arteries (70.1% versus 59.5%, P = 0.008), (48.1% versus 28.9%, P < 0.001), (23.9% versus 16%, P = 0.018), respectively. L-SA had a higher prevalence of mixed plaque (non-calcified > calcified) (19.6% versus 16.4%) and noncalcified plaque (51.9% versus 31.7%), and a lower prevalence of calcified plaque (8.9% versus 23.3%) and mixed plaque (calcified > non-calcified) (19.6% versus 28.6%) than R-SA, P < 0.001. The distribution of plaque type in the SA and extracranial vertebral artery (EVA) were significantly different between ACS and PCS. The soft plaque thickness of SA in PCS was significantly greater than that in ACS (3.85 ± 1.27 versus 3.51 ± 1.04, P = 0.032). CONCLUSIONS: Atherosclerotic plaque prevalence and characteristics vary in different segments, sides and between ACS and PCS. These differences should be noted during plaque diagnosis.


Assuntos
Isquemia Encefálica , Placa Aterosclerótica , Acidente Vascular Cerebral , Artérias Carótidas , Humanos , Placa Aterosclerótica/diagnóstico por imagem , Prevalência , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/epidemiologia
18.
Neurol Sci ; 42(9): 3605-3613, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34236554

RESUMO

BACKGROUND: Atherosclerosis is the most common cause of ischemia stroke. Computed tomographic angiography (CTA) and digital subtraction angiography (DSA) are used to evaluate the degree of lumen stenosis. However, these examinations are invasive and can only reveal mild to moderate stenosis. High-resolution magnetic resonance imaging (HRMRI) seems a more intuitive way to show the pathological changes of vascular wall. Hence, we conducted a systematic retrospective study to determine the characteristics of symptomatic plaques in patients with intracranial atherosclerosis on HRMRI and their association with the occurrence and recurrence of ischemic stroke events. METHODS: The PubMed database was searched for relevant studies reported from January 31, 2010, to October 31, 2020. RESULTS: We selected 14 clinical outcome studies. We found that plaque enhancement and positive remodeling on HRMRI indicate symptomatic plaques. Besides, intraplaque hemorrhage and positive remodeling index are closely related to the occurrence of stroke. However, it is still controversial whether the initial enhancement of plaque and the occurrence and recurrence of stroke are related. There is also no significant correlation between vascular stenosis and symptomatic plaque or the occurrence and recurrence of ischemic stroke. CONCLUSION: High-resolution magnetic resonance imaging can be used as an assessment tool to predict the risk of stroke onset and recurrence in patients with atherosclerosis, but further research is also needed.


Assuntos
Isquemia Encefálica , Arteriosclerose Intracraniana , AVC Isquêmico , Placa Aterosclerótica , Acidente Vascular Cerebral , Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/epidemiologia , Humanos , Arteriosclerose Intracraniana/complicações , Arteriosclerose Intracraniana/diagnóstico por imagem , Angiografia por Ressonância Magnética , Imageamento por Ressonância Magnética , Placa Aterosclerótica/diagnóstico por imagem , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/epidemiologia
20.
Radiologe ; 61(8): 752-757, 2021 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-34232343

RESUMO

Every year, about 270,000 strokes occur in Germany. In the entire DACH region (Germany, Austria, Switzerland), more than 310,000 cases are reported each year. Two thirds of the surviving patients are dependent on external assistance after the stroke. Increasingly, imaging data are becoming the focus of treatment decisions. These data provide critical information about the location and extent of vessel occlusion, infarct size, volume of salvageable brain tissue, and degree of collateralization. Certified stroke units and stroke networks already specialize in state-of-the-art therapeutic options, but they need additional information technology tools to deliver the right therapy to the right patient population as quickly as possible. For multidisciplinary, seamless support in stroke care, both prehospital and in-hospital processes need to be optimized. This article presents a concept for supraregional stroke care by means of networking all involved actors in the prehospital as well as in the in-hospital area. Further needs analyses should ensure the implementation as well as the generalizability to different regions.


Assuntos
Isquemia Encefálica , Serviços Médicos de Emergência , AVC Isquêmico , Acidente Vascular Cerebral , Áustria , Alemanha , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia
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