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1.
Int Wound J ; 21(4): e14851, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38563121

RESUMO

Scarring following oral and maxillofacial trauma can have significant aesthetic and functional repercussions. Recombinant human epidermal growth factor (rhEGF) has emerged as a potential therapeutic agent to enhance wound healing and minimise scar formation. This retrospective study analysed data from March 2020 to June 2023 at a single institution. A total of 105 patients were divided into a control group (n = 70) receiving standard treatment and an observation group (n = 35) receiving standard treatment plus rhEGF. The primary outcomes were the incidence of scar hyperplasia and infection rates, with the secondary outcome being scar aesthetics measured by the visual analogue scale (VAS). No significant differences were found in baseline characteristics between the two groups. The observation group showed a significant reduction in scar hyperplasia (14.3% vs. 57.1%, χ2 = 20.98, p < 0.01) and infection rates (5.7% vs. 21.4%, χ2 = 4.246, p < 0.05) compared to the control group. VAS scores indicated a superior aesthetic outcome in the observation group at all post-treatment timepoints (p < 0.01). rhEGF treatment in oral and maxillofacial trauma patients resulted in favourable healing outcomes and reduced scar formation, improving aesthetic results. These findings highlight the therapeutic potential of rhEGF and underscore the need for larger-scale trials to further investigate its benefits.


Assuntos
Cicatriz , Traumatismos Maxilofaciais , Humanos , Cicatriz/tratamento farmacológico , Hiperplasia/tratamento farmacológico , Estudos Retrospectivos , Proteínas Recombinantes/uso terapêutico , Fator de Crescimento Epidérmico/uso terapêutico , Cicatrização , Traumatismos Maxilofaciais/tratamento farmacológico
2.
AJR Am J Roentgenol ; 218(3): 517-525, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34549604

RESUMO

BACKGROUND. The composition of noncalcified portions of carotid atherosclerotic plaque is an important marker of plaque vulnerability and ischemia risk. OBJECTIVE. The purpose of this study was to assess the utility of dual-layer spectral detector CTA (DLCTA) parameters for characterization of carotid plaque components with histologic results from carotid endarterectomy as the reference. METHODS. Seven patients (five men, two women; mean age, 61.6 ± 8.5 [SD] years) with carotid plaque awaiting carotid endarterectomy were prospectively enrolled and underwent preoperative supraaortic DLCTA. A neuroradiologist and pathologist performed joint slice-by-slice review of histologic slices of resected plaques and CTA images. With the use of anatomic landmarks, ROIs were placed on noncalcified components (lipid-rich necrotic core [LRNC], intraplaque hemorrhage [IPH], fibrous tissue, loose matrix) on CTA images and compared with corresponding histologic slices. For each ROI, attenuation was recorded for conventional polyenergetic images (CTPI) and virtual monoenergetic images with energy ranging from 40 to 140 keV (CT40-140keV), attenuation spectrum curve slope was calculated, and Z-effective value (representing effective atomic number) was recorded. DLCTA parameters were compared among plaque components. RESULTS. Seven plaques with a total of 65 slices and 364 ROIs (159 fibrous tissue, 96 LRNC, 86 loose matrix, 23 IPH) were analyzed. All parameters (CTPI, CT40-140keV, slope from 40 to 140 keV, Z-effective value) had significant differences between LRNC and the other components (all p < .001). For example, mean CTPI was 37.1 ± 15.1 HU for LRNC, 58.4 ± 21.6 HU for IPH, 69.7 ± 20.5 HU for fibrous tissue, and 69.6 ± 19.6 HU for loose matrix. Mean CT40keV was 28.1 ± 36.7 HU for LRNC, 87.5 ± 48.9 HU for IPH, 106.3 ± 47.5 HU for fibrous tissue, and 102.6 ± 48.0 HU for loose matrix. AUC for differentiating LRNC from other components was highest (0.945) for CT40kev and decreased with higher energy; AUC for CTPI was 0.908. CT40kev also had highest accuracy (90.4%); at a cutoff of 55.7 HU, CT40kev had 88.5% sensitivity and 91.0% specificity. For differentiating IPH from fibrous tissue and loose matrix, AUC was highest at 0.652 for CTPI and 0.645 for CT40kev. CONCLUSION. DLCTA showed strong performance in differentiating LRNC from other noncalcified plaque components; CT40kev had highest accuracy, outperforming CTPI. CLINICAL IMPACT. DLCTA parameters may help characterize carotid plaque composition as a marker of vulnerable plaque and ischemia risk.


Assuntos
Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/cirurgia , Angiografia por Tomografia Computadorizada/métodos , Endarterectomia/métodos , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
3.
Acta Radiol ; 62(6): 766-775, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32660319

RESUMO

BACKGROUND: Multiple methods have been used to analyze fluid-attenuated inversion recovery (FLAIR) vascular hyperintensities (FVHs) which may represent collaterals in patients with acute ischemic stroke (AIS); however, there is no consensus between methods. PURPOSE: To compare three frequently used FVH methods for predicting early infarct volume and clinical outcome in patients with AIS. MATERIAL AND METHODS: Patients with AIS in middle cerebral artery territory were recruited. FVHs were evaluated using extensive FVHs, FVH-diffusion-weighted imaging (DWI) mismatch, and FVH-in/out-DWI. Infarct volume at baseline and day 7 were measured. Early neurological improvement (ENI) was assessed. Good outcomes were defined by modified Rankin Scale scores of 0-2 at 90 days. RESULTS: Fifty-one patients were included. ENI was 55.6% in patients with extensive FVHs and 23.3% in those without (P = 0.024). Patients with extensive FVHs had smaller infarct volume growth at seven days than those without (P = 0.041). ENI was 48.3% in patients with FVH-DWI mismatch and 15.8% in those without (P = 0.021). Patients with FVH-DWI mismatch had smaller infarct volumes at seven days than those without (P = 0.038). Patients with FVH-out-DWI had smaller baseline infarct volumes, smaller seven-day volumes, and smaller infarct growth than those with FVH-in-DWI (P<0.001, P<0.001, and P = 0.031, respectively). In multivariate logistic regression analysis, the infarct growth at seven days negatively independently predicted ENI (OR = 0.737, 95% CI 0.593-0.915, P = 0.006). However, none of the FVH classifications could predict a good 90-day outcome. CONCLUSION: Patients with extensive FVHs or FVH-DWI mismatch tend to have early favorable clinical outcome. FVH-out-DWI being associated with smaller infarct growth may also indicate early favorable clinical outcome.


Assuntos
AVC Isquêmico/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Doença Aguda , Encéfalo/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
4.
J Comput Assist Tomogr ; 43(4): 547-552, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31162235

RESUMO

PURPOSE: The purpose of this study was to investigate whether alterations of regional neural function in children with diffuse intrinsic pontine glioma (DIPG) had manifested deficit in behavioral inhibition using resting-state functional MRI (rs-fMRI). METHODS: There were 17 participants with DIPG who took part in the study. Eight children were with deficit in behavioral inhibition, whereas the other 9 children did not obtain deficit in behavioral inhibition. Five healthy children with age, sex, and education matched to the study group also participated as the control group. These 3 groups underwent rs-fMRI, and the results were then converted to amplitude of low-frequency fluctuation (ALFF) data. Amplitude of low-frequency fluctuation data were further analyzed by single-factor analysis of variance comparing among 3 groups based on the whole brain levels. Amplitude of low-frequency fluctuation results were subjected to t test of voxel-wised comparison to derive the rs-fMRI brain function differences between the 2 DIPG groups. The Pearson correlation between ALFF values of abnormal regions found in 3 groups and the scores obtained according to the Child Behavior Checklist were analyzed. RESULTS: The 3 groups had shown significant differences in terms of the ALFF results, with the ALFF increased in several brain regions (P < 0.05, corrected with AlphaSim, clusters >59 voxels), which include left supramarginal gyrus, left dorsolateral superior frontal gyrus, right precentral gyrus, and right middle frontal gyrus. Participants with deficit in behavioral inhibition had shown significant differences (ALFF decreased) in several brain regions, including left dorsolateral superior frontal gyrus and right fusiform gyrus (P < 0.05, corrected with AlphaSim, clusters >123 voxels), whereas other brain regions had shown ALFF increased, including left supramarginal gyrus, left middle frontal gyrus, and right medial superior frontal gyrus (P < 0.05, corrected with AlphaSim, clusters >123 voxels). There was no significant correlation between ALFF values and Child Behavior Checklist scores (P > 0.05). CONCLUSIONS: These findings of focal spontaneous hyperfunction and hypofunction, which correlate with deficit in behavioral inhibition processing, and the abnormal brain regions are considered to be inefficient (in regions of the brain that may relate to compensatory brain and behavioral functioning, and it may be that the brain region needs to exert extra energy to perform a task to the same degree as the control group) or inability (inability in a certain region, or underpowered), pointing to a pathophysiologic process in executive dysfunction.


Assuntos
Neoplasias do Tronco Encefálico , Encéfalo , Transtornos do Comportamento Infantil , Imageamento por Ressonância Magnética/métodos , Adolescente , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Neoplasias do Tronco Encefálico/diagnóstico por imagem , Neoplasias do Tronco Encefálico/fisiopatologia , Estudos de Casos e Controles , Criança , Transtornos do Comportamento Infantil/diagnóstico por imagem , Transtornos do Comportamento Infantil/fisiopatologia , Pré-Escolar , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino
5.
J Stroke Cerebrovasc Dis ; 27(11): 3387-3392, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30145026

RESUMO

BACKGROUND: Deep subcortical infarction is a major subtype of stroke in middle cerebral artery (MCA) territory. This study aims to evaluate the relationship between characteristics of MCA plaque and features of deep subcortical infarction. METHODS: Patients with recent acute ischemic stroke and deep subcortical infarction were prospectively enrolled. Both multicontrast brain sequences and 3D high-resolution vessel wall imaging (VWI) sequences were scanned for all patients. MCA plaque characteristics, including plaque presence, location, maximum vessel wall thickness (Max WT), signal intensity and luminal stenosis, and deep subcortical infarction features, including lowest infarct layer index (LILI), area, volume, maximum area, and infarct quantity were evaluated. Infarct feature differences were compared between MCA plaque+ group and MCA plaque- group. The correlations between MCA plaque characteristics and deep subcortical infarction features were analyzed. RESULTS: Of all 50 patients included in this study, 30 (60%) had MCA plaques. All deep subcortical infarction was single lesion for patients without MCA plaque. The average number of deep subcortical infarction for patients with MCA plaque was 3.10 ± 4.44. The LILI (P = .036) and infarct quantity (P = .030) showed significant differences between 2 groups. Max WT (P = .025) and stenosis degree (P = .023) were negatively correlated with LILI. Intraplaque hemorrhage was positively correlated with maximum area (P = .029) and infarct volume (P = .030). CONCLUSIONS: MCA plaque characteristics were correlated with deep subcortical infarct features. Magnetic resonance VWI may provide more information for etiological evidence of deep subcortical infarction.


Assuntos
Angiografia Cerebral/métodos , Infarto Cerebral/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Arteriosclerose Intracraniana/diagnóstico por imagem , Angiografia por Ressonância Magnética , Adulto , Idoso , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos
6.
Stroke ; 48(9): 2412-2418, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28775139

RESUMO

BACKGROUND AND PURPOSE: Permeability surface (PS) on computed tomographic perfusion reflects blood-brain barrier permeability and is related to hemorrhagic transformation (HT). HT of deep middle cerebral artery (MCA) territory can occur after recanalization of proximal large-vessel occlusion. We aimed to determine the relationship between HT and PS of deep MCA territory. METHODS: We retrospectively reviewed 70 consecutive acute ischemic stroke patients presenting with occlusion of the distal internal carotid artery or M1 segment of the MCA. All patients underwent computed tomographic perfusion within 6 hours after symptom onset. Computed tomographic perfusion data were postprocessed to generate maps of different perfusion parameters. Risk factors were identified for increased deep MCA territory PS. Receiver operating characteristic curve analysis was performed to calculate the optimal PS threshold to predict HT of deep MCA territory. RESULTS: Increased PS was associated with HT of deep MCA territory. After adjustments for age, sex, onset time to computed tomographic perfusion, and baseline National Institutes of Health Stroke Scale, poor collateral status (odds ratio, 7.8; 95% confidence interval, 1.67-37.14; P=0.009) and proximal MCA-M1 occlusion (odds ratio, 4.12; 95% confidence interval, 1.03-16.52; P=0.045) were independently associated with increased deep MCA territory PS. Relative PS most accurately predicted HT of deep MCA territory (area under curve, 0.94; optimal threshold, 2.89). CONCLUSIONS: Increased PS can predict HT of deep MCA territory after recanalization therapy for cerebral proximal large-vessel occlusion. Proximal MCA-M1 complete occlusion and distal internal carotid artery occlusion in conjunction with poor collaterals elevate deep MCA territory PS.


Assuntos
Hemorragia Cerebral/etiologia , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/diagnóstico por imagem , Idoso , Barreira Hematoencefálica , Permeabilidade Capilar , Artéria Carótida Interna/diagnóstico por imagem , Estudos de Casos e Controles , Angiografia Cerebral , Angiografia por Tomografia Computadorizada , Procedimentos Endovasculares , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/terapia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Imagem de Perfusão , Curva ROC , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia , Trombectomia , Terapia Trombolítica , Tomografia Computadorizada por Raios X
7.
Magn Reson Med ; 78(5): 1944-1949, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28054416

RESUMO

PURPOSE: To demonstrate the capability of the fractional motion (FM) model for describing anomalous diffusion in cerebral gliomas and to assess the potential feasibility of FM for grading these tumors. METHODS: Diffusion MRI images were acquired from brain tumor patients using a special Stejskal-Tanner diffusion sequence with variable diffusion gradient amplitudes and separation times. Patients with histopathologically confirmed gliomas, including astrocytic and oligoastrocytic tumors, were selected. The FM-related parameters, including the Noah exponent ( α), the Hurst exponent ( H), and the memory parameter ( µ=H-1/α), were calculated and compared between low- and high-grade gliomas using a two-sample t-test. The grading performance was evaluated using the receiver operating characteristic analysis. RESULTS: Twenty-two patients were included in the present study. The calculated α, H, and µ permitted the separation of tumor lesions from surrounding normal tissues in parameter maps and helped differentiate glioma grades. Moreover, α showed greater sensitivity and specificity in distinguishing low- and high-grade gliomas compared with the apparent diffusion coefficient. CONCLUSION: The FM model could improve the diagnostic accuracy in differentiating low- and high-grade gliomas. This improved diffusion model may facilitate future studies of neuro-pathological changes in clinical populations. Magn Reson Med 78:1944-1949, 2017. © 2017 International Society for Magnetic Resonance in Medicine.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Glioma/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Movimento , Curva ROC
8.
Med Sci Monit ; 21: 3279-90, 2015 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-26510514

RESUMO

BACKGROUND: Hemodynamics play an important role in the development and progression of carotid atherosclerosis, and may be important in the assessment of plaque vulnerability. The aim of this study was to develop a system to assess the hemodynamics of carotid atherosclerotic plaques using subject-specific fluid-structure interaction (FSI) models based on magnetic resonance imaging (MRI). MATERIAL AND METHODS: Models of carotid bifurcations (n=86 with plaques from 52 patients, n=14 normal carotids from 12 participants) were obtained at the Department of Radiology, Beijing Tian Tan Hospital between 2010 and 2013. The maximum von Mises stress, minimum pressure, and flow velocity values were assessed at the most stenotic site in patients, or at the carotid bifurcations in healthy volunteers. Results of one-way FSI were compared with fully-coupled FSI for the plaques of 19 randomly selected models. RESULTS: The maximum von Mises stress and the minimum pressure and velocity were significantly increased in the stenosis group compared with controls based on one-way FSI (all P<0.05). The maximum von Mises stress and the minimum pressure were significantly higher and the velocity was significantly lower based on fully coupled FSI compared with on-way FSI (all P<0.05). Although there were differences in numerical values, both methods were equivalent. The maximum von Mises stress of vulnerable plaques was significantly higher than stable plaques (P<0.001). The maximum von Mises stress of the group with fibrous cap defect was significantly higher than the group without fibrous cap defect (P=0.001). CONCLUSIONS: The hemodynamics of atherosclerotic plaques can be assessed noninvasively using subject-specific models of FSI based on MRI.


Assuntos
Doenças das Artérias Carótidas/patologia , Modelos Cardiovasculares , Placa Aterosclerótica/patologia , Adulto , Idoso , Artérias Carótidas/patologia , Feminino , Voluntários Saudáveis , Hemodinâmica , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
9.
Acta Radiol ; 56(3): 347-54, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24676083

RESUMO

BACKGROUND: Histopathological studies have shown significant differences in plaque components and surface conditions between upstream and downstream of the stenosis. It can be deduced that the flow status near the plaques is different from the flow status at the upstream side, stenosis center, or downstream side of the plaque. PURPOSE: To study the hemodynamic parameter distribution in different locations near atherosclerotic plaques in the carotid arteries with different stenosis degrees. MATERIAL AND METHODS: Eleven patients were recruited in this study. CE-MRA was performed to obtain the carotid three-dimensional surface data and the stenosis degrees were calculated. The hemodynamic parameters including wall shear stress (WSS), pressure, and velocity near the plaques were obtained by computational fluid dynamic (CFD) method. Local hemodynamics parameters were analyzed and compared between different stenosis degree groups, and between upstream, stenosis center, and downstream sides of plaques. Relative ratio of velocity, WSS, and pressure values in different locations was calculated and compared. RESULTS: Fourteen carotid arteries (with 4 mild, 6 moderate, and 4 severe stenosis) were analyzed. Significant differences were found in Pressure max (P = 0.025), Pressure mean (P = 0.020), and Pressure min (P = 0.026) between three stenosis groups. It showed significant differences in Vmin (P < 0.001) and WSSmin (P < 0.001) between three different locations. It showed upstream to downstream ratio of WSSmax (P = 0.034) and WSSmean value (P = 0.042) was significantly different between mild and moderate/severe groups. Significant differences were found in upstream to stenosis center ratio of Pressure max value (P = 0.018), Pressure mean value (P = 0.029), and Pressure min value (P = 0.026), as well as in stenosis center to downstream ratio of Pressure min value (P = 0.042). CONCLUSION: Velocity, WSS, pressure, and relative ratio of these parameters have certain trends in distribution around the plaques in the carotid arteries.


Assuntos
Doenças das Artérias Carótidas/fisiopatologia , Hemodinâmica , Angiografia por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo/fisiologia , Artérias Carótidas/fisiopatologia , Simulação por Computador , Meios de Contraste , Feminino , Humanos , Aumento da Imagem/métodos , Imageamento Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Fluxo Sanguíneo Regional/fisiologia , Índice de Gravidade de Doença
10.
Chin J Cancer Res ; 27(3): 231-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26157319

RESUMO

OBJECTIVE: To evaluate the feasibility of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for predicting tumor response to radiotherapy in patients with suspected primary central nervous system (CNS) germ cell tumors (GCTs). METHODS: DCE-MRI parameters of 35 patients with suspected primary CNS GCTs were obtained prior to diagnostic radiation, using the Tofts and Kermode model. Radiosensitivity was determined in tumors diagnosed 2 weeks after radiation by observing changes in tumor size and markers as a response to MRI. Taking radiosensitivity as the gold standard, the cut-off value of DCE-MRI parameters was measured by receiver operating characteristic (ROC) curve. Diagnostic accuracy of DCE-MRI parameters for predicting radiosensitivity was evaluated by ROC curve. RESULTS: A significant elevation in transfer constant (K(trans)) and extravascular extracellular space (Ve) (P=0.000), as well as a significant reduction in rate constant (Kep) (P=0.000) was observed in tumors. K(trans), relative K(trans), and relative Kep of the responsive group were significantly higher than non-responsive groups. No significant difference was found in Kep, Ve, and relative Ve between the two groups. Relative K(trans) showed the best diagnostic value in predicting radiosensitivity with a sensitivity of 100%, specificity of 91.7%, positive predictive value (PPV) of 95.8%, and negative predictive value (NPV) of 100%. CONCLUSIONS: Relative K(trans) appeared promising in predicting tumor response to radiation therapy (RT). It is implied that DCE-MRI pre-treatment is a requisite step in diagnostic procedures and a novel and reliable approach to guide clinical choice of RT.

12.
Chin Med Sci J ; 29(3): 139-43, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25264880

RESUMO

UNLABELLED: OBJECTIVE To explore the perihematomal perfusion typing and spot sign on computed tomography angiography (CTA) source images in order to assist in individualizing therapeutic decisions for patients with intracerebral hemorrhage by possibly forecasting perihematomal ischemia and hematoma enlargement. METHODS We examined 58 patients with spontaneous intracerebral hemorrhage by computed tomography perfusion and CTA within 6 hours after symptom onset. Hematoma volumes were determined from non-contrast CT images and compared between first and second CT images. The perfusion of hematoma region and perihematoma region was evaluated for presence or absence of the perihematomal penumbra. Three kinds of perihematoma perfusion typing were defined according to the perfusion of hematoma region and perihematoma region. CTA source images was reviewed to make sure presence or absence of the spot sign. RESULTS Finally, 53 patients (34 males, 19 females) were enrolled in our study according to exclusion criteria. Finally, 21 patients were classified into the normal group, 23 patients were classified into the mild group, and 9 patients were classified into the severe group. There were significant differences in hematoma size between the presence and absence of the perihematomal penumbra group (P<0.05). Thirteen (24.5%) patients presented with spot sign. Hematoma expansion occurred in 15 (28.3%) patients on follow-up. In which 12 patients were with spot sign. Sensitivity, specificity, positive predictive value, and negative predictive value for expansion were 80.0%, 97.4%, 92.3%, and 92.5%, respectively. CONCLUSION: In acute intracerebral hemorrhage patients, the perihematoma perfusion typing and CTA spot sign provide more radiological information that might assist in individualizing therapeutic decisions for patients by possibly forecasting perihematomal ischemia and hematoma enlargement.


Assuntos
Hemorragia Cerebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
13.
Eur Radiol ; 23(7): 1846-54, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23508276

RESUMO

OBJECTIVES: To evaluate the association between dynamic progressive enhancing foci ("dynamic spot sign") in acute haematoma on CT perfusion source images (CTP-SI) and haematoma expansion. METHODS: One hundred twelve consecutive patients with spontaneous intracerebral haemorrhage according to unenhanced CT, CTP and CT angiography within 6 h of symptom onset were prospectively evaluated. Patients were dichotomised according to the presence/absence of the dynamic spot sign on CTP-SI in haematoma. The predictive value of haematoma expansion was analysed. RESULTS: Haematoma expansion was detected in 28 patients (25.0 %) on follow-up unenhanced CT images. Thirty patients (26.8 %) demonstrated the dynamic spot sign on CTP-SI, about 83.3 % of patients with haematoma expansion (P < 0.001). Sensitivity, specificity, positive predictive value, negative predictive value and kappa value for expansion were 89.3 %, 94.0 %, 96.3 %, 83.3 % and 0.814, respectively. In multiple regression, the presence of the CTP dynamic spot sign within acute haematomas independently predicted haematoma expansion; the univariate analysis OR value was 131.667 (29.386-590.289), P < 0.0001. Moreover, the multivariate analysis CTP dynamic spot sign OR value was 203.996 (32.123-1295.488), P < 0.0001. CONCLUSIONS: The CTP-SI dynamic spot sign is associated with acute haematoma expansion, is more direct in showing active ongoing bleeding and has a higher predictive value than the CTA spot sign. KEY POINTS: • It is important to identify potential progression of spontaneous intracerebral haemorrhage. • Dynamic enhancement within CT perfusion source images is associated with haemorrhage expansion. • The CTP dynamic spot sign may be present throughout arterial to venous phase imaging. • The CTP dynamic spot sign carries a higher predive value for haematoma expansion than CTA.


Assuntos
Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Cerebral/métodos , Feminino , Hematoma/diagnóstico , Hematoma/diagnóstico por imagem , Hemorragia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Perfusão , Valor Preditivo dos Testes , Estudos Prospectivos , Análise de Regressão , Sensibilidade e Especificidade
14.
Front Neurol ; 14: 1154823, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37560447

RESUMO

Objective: This study aimed to investigate the diagnostic performance of volume mismatch sign on discriminating paramedial bithalamic tumors from non-tumors. Methods: In this study, we recruited patients with tumors or non-tumors of the paramedial bithalamus. We confirmed the diagnosis by pathology, laboratory tests documented in medical records, medical imaging at the baseline, or through at least 1 year of follow-up. Cases with paramedial thalamic lesions on only one side or purely midbrain illnesses were excluded. Additionally, any case without involvement of the medial thalami (i.e., those with one or both-sided anterior, lateral, or posterior thalamic lesions) was excluded. Two neuroradiologists were trained independently to evaluate volume mismatch sign on magnetic resonance T2-weighted images or T2 fluid-attenuated inversion recovery images. A positive volume mismatch sign means that the ratio of the larger-sided lesion volume to the smaller-sided lesion volume is >150%. The volume of each lesion was calculated by multiplying the anteroposterior diameter by the left-right diameter and by the height of the lesion and then dividing by 2. The kappa value was calculated to show the consistency between the two observers. The chi-square test was used to evaluate differences in volume mismatch sign between the bilthalamic midline tumor and non-tumor groups. The positive (PPV) and negative (NPV) predictive values, sensitivity, and specificity were calculated to evaluate the ability of volume mismatch sign to differentiate paramedial bilateral thalamus tumors from non-tumors. A two-tailed P ≤ 0.05 was considered to be statistically significant. The analyses were performed using the statistical software SPSS version 26. Results: A total of 96 patients were enrolled in this study between March 2012 and October 2022. A high agreement between the two observers on the volume mismatch sign of bilateral paramedian thalamic diseases was found, and the Kappa value was 0.828. A statistically significant difference was observed for the volume mismatch sign between the paramedial bithalamic tumor and the non-tumorous groups (χ2 = 35.465, P < 0.001). The presence of volume mismatch sign in paramedial bithalamic illnesses predicted the presence of tumors with a sensitivity and specificity of 69.2% and 90.9%, respectively, and PPV and NPV were 90.0% and 71.4%. Conclusion: Volume mismatch sign may indicate tumors in paramedian bithalamic diseases.

15.
Biochem Biophys Rep ; 36: 101559, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37881410

RESUMO

Background: Recently, the antioxidant properties of the natural compound, selenomethionine (Se-Met), have been recognized. However, its effect on the osteogenic mineralization of the Wnt/ß-Catenin pathway under conditions of oxidative stress and inflammation remain unclear. Methods: This study utilized tert-butyl hydroperoxide (TBHP) to simulate oxidative stress and inflammation. Se-Met was then subsequently used to inhibit these effects in vitro. Results: TBHP induces oxidative stress and inflammatory responses by increasing the expression of reactive oxygen species and NLRP3, whereas decreasing the expression of GPX4, thereby inhibiting the viability of MC3T3-E1 cells. TBHP further promotes lipid peroxidation and damages the ultrastructure of mitochondria. Furthermore, TBHP inhibits the expression levels of ß-Catenin, thereby reducing the activity of the Wnt pathway, which in turn suppresses the osteogenic differentiation and mineralization capacity. Importantly, Se-Met significantly alters the aforementioned responses to enhance expression levels of Wnt pathway-related proteins and improving the osteogenic differentiation and mineralization capacity of the cells. Conclusion: Se-Met enhances antioxidant and anti-inflammatory responses in MC3T3-E1 cells via the Wnt/ß-Catenin signaling pathway to promote osteogenesis. Thus, Se-Met plays a crucial role in the field of bone homeostasis, and presents an opportunity for the future development of novel drugs for treating osteoporosis and maintaining bone stability. However, further detailed preclinical animal studies are required to generate solid and reliable data to aid this development.

16.
Eur J Radiol ; 167: 111045, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37586303

RESUMO

PURPOSE: Atherosclerotic plaques of carotid artery (CA) and middle cerebral artery (MCA) are important causes of acute ischemic stroke (AIS). This study was designed to jointly assess the plaque distribution and features of CA and MCA in AIS patients with pial infarction (PI) and perforating artery infarction (PAI), and to investigate the associations between plaque characteristics and ischemic infarction patterns. METHODS: Imaging data of sixty-five patients from a cross-sectional study were reviewed. All the patients had acute infarction in the MCA territory on diffusion weighted imaging (DWI) and underwent CA and MCA vessel wall imaging (VWI). The CA and MCA plaque presence and high-risk features on the ipsilateral side of infarction were analyzed. The brain infarction lesions were divided into PI group vs. non-PI group, and PAI group vs. non-PAI group. Different plaque distribution types and plaque features were compared in each two groups, and their associations were investigated using binary logistic regression. RESULTS: Sixty-five patients (mean age, 54.6 ± 10.1 years; 61 men) were included. The CA high-risk plaque (OR: 5.683 [1.409-22.929], P = 0.015) and MCA plaque presence (OR: 3.949 [1.397-11.162], P = 0.010) were significantly associated with PI. MCA plaques that involved the orifice of the perforating arteries were significantly associated with PAI (OR: 15.167 [1.851-124.257], P = 0.011). CONCLUSION: CA and MCA plaques show distinct distribution and high-risk features in patients with PI and PAI. Combined intracranial and extracranial arteries imaging should be considered for the evaluation of the symptomatic ischemic patients.


Assuntos
Estenose das Carótidas , Arteriosclerose Intracraniana , AVC Isquêmico , Placa Aterosclerótica , Acidente Vascular Cerebral , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/patologia , Acidente Vascular Cerebral/patologia , Placa Aterosclerótica/complicações , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/patologia , AVC Isquêmico/complicações , AVC Isquêmico/patologia , Estudos Transversais , Artérias Carótidas/patologia , Infarto Encefálico/patologia , Estenose das Carótidas/patologia , Imageamento por Ressonância Magnética/métodos , Arteriosclerose Intracraniana/patologia , Infarto da Artéria Cerebral Média , Angiografia por Ressonância Magnética/métodos
17.
Analyst ; 137(24): 5705-9, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-23099775

RESUMO

We report a sensitive approach for SERS detection of cytochrome c using target binding-induced conformational changes of signal transduction probe (STP). STP labeled with a SERS-active molecule, carboxy-X-rhodamine (ROX), is immobilized on the substrate where the formation of a rigid triplex switching structure with aptamers does not allow SERS amplification to take place. The target binding event leads to an enhancement in SERS intensity of ROX adsorbed on the gold surface. Meanwhile, we found that an appropriate STP surface density could shield the SERS signal produced by protein adsorption which would foul the sensing surface. In addition, cytochrome c aptamers used were not the original sequence but reorganized in the nonspecific binding site to adapt to our design. This method provides a low detection limit of 2 nM (10 fmol within 5 µL sample solution), and shows good selectivity toward cytochrome c compared to interfering proteins such as hemoglobin and immunoglobulin G. The general strategy of the method can also be extended to aptamer or DNA based sensors.


Assuntos
Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/metabolismo , Técnicas Biossensoriais/métodos , Citocromos c/análise , DNA/química , DNA/metabolismo , Análise Espectral Raman , Aptâmeros de Nucleotídeos/genética , Sequência de Bases , Citocromos c/química , Citocromos c/metabolismo , DNA/genética , Modelos Moleculares , Conformação Proteica , Propriedades de Superfície
18.
Acta Radiol ; 53(2): 203-7, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22156010

RESUMO

BACKGROUND: Cerebral microbleeds (CMBs) detected by gradient-echo MRI have been proven to be a potential risk factor for further bleeding, while the association between CMBs and the first onset of intracerebral hemorrhage has not been well investigated. PURPOSE: To analyze the association between CMBs and the first onset of primary intracerebral hemorrhage (pICH). MATERIAL AND METHODS: Two hundred and two consecutive inpatients with ICH and 234 consecutive outpatients without ICH as control group were enrolled in this study. MR imaging including T2*-GRE, T(1)W, T(2)W and fluid attenuated inversion recovery (FLAIR) sequences were performed to detect CMBs and other abnormalities. Prevalence, distribution, and grades of CMBs, as well as the location and size of the intracerebral hematoma were analyzed, respectively. Comparison was made between pICH and control group. Logistic analysis was performed to evaluate the association between CMBs and ICH. The correlation between hematoma size and CMBs grade/numbers was analyzed. RESULTS: CMBs were detected in 140 patients in pICH (69.3%) group and 62 patients in control group (26.5%). The incidence of CMBs in pICH group was significantly higher than that in control group (P < 0.0001). As the logistic regression analysis results, CMBs was the risk factor associated with ICH, with modulation OR value of 8.363 (95% CI 5.210-13.421). The volume of ICH with CMBs was 12.57 ± 17.23 mL, and the volume of ICH without CMBs was 17.77 ± 26.97 mL. Negative correlation was demonstrated between CMBs number and ICH volume (r(s) = -0.1769, P = 0.0118), as well as between CMBs grade and hematoma volume (r(s) = -0.1185, P = 0.1557). CONCLUSION: CMBs may be an independent risk factor for the first onset of intracerebral hemorrhage.


Assuntos
Hemorragia Cerebral/epidemiologia , Hemorragia Cerebral/patologia , Imageamento por Ressonância Magnética/métodos , Idade de Início , Encéfalo/patologia , Feminino , Hematoma/epidemiologia , Hematoma/patologia , Humanos , Incidência , Masculino , Microcirculação , Pessoa de Meia-Idade , Variações Dependentes do Observador , Prevalência , Estudos Retrospectivos , Fatores de Risco , Estatísticas não Paramétricas
19.
Neurol Res ; 44(7): 583-590, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35001834

RESUMO

OBJECTIVES: To investigate the changes of prominent vessel sign (PVS) and susceptibility vessel sign (SVS) in acute ischemic stroke (AIS) patients with successful and non-successful vascular recanalization treatment, and to study the associations between the susceptibility-weighted imaging (SWI) findings and early clinical and imaging prognosis. METHODS: Thirty-five patients with the acute MCA territory infarction were retrospectively included and classified into Groupre (n = 25) and Groupnon (n = 10) according to the success of vascular recanalization. NIHSS was used for clinical assessment. PVS and DWI were analyzed using ASPECT scores. Baseline, post-treatment, the changes of PVS and SVS, and SVS length were recorded and compared between two groups. Correlation analysis was performed between SWI factors and early post-treatment clinical and imaging factors. RESULTS: The mean PVSpre value was 5.20 ± 1.76 and PVSpost was 8.20 ± 1.86. PVSpre and PVSpost showed statistical significance between Groupre and Groupnon (both p < 0.001). A significant difference wasfound in SVSpost(+) (p < 0.001), SVSpost-pre(+) (p = 0.001), SVSpost-pre length (p = 0.036) and SVSpost length (p = 0.001) between the two groups.  A positive correlation was found between PVSpre and DWIpost (p < 0.001, r = 0.564). There were positive correlations between PVS-DWI mismatch and NIHSSpost in Groupre (p = 0.042, r = 0.410) and in Groupnon (p = 0.006, r = 0.789). CONCLUSIONS: PVS and SVS changes are influenced by the success of vascular recanalization. However, the changes are unrelated to either early clinical or imaging outcomes in AIS patients. PVS-DWI mismatch can be taken as an imaging biomarker for early clinical outcomes, both for patients with or without successful vascular recanalization.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/terapia , Humanos , Infarto da Artéria Cerebral Média , Angiografia por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia
20.
Quant Imaging Med Surg ; 12(12): 5462-5473, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36465823

RESUMO

Background: To investigate the distribution and regional variation of wall shear stress (WSS) in the curved middle cerebral artery (MCA) in healthy individuals using four-dimensional (4D) flow magnetic resonance imaging (MRI). Methods: A total of 44 healthy participants (18 males; mean ages: 27.16±5.69 years) were included in this cross-sectional study. The WSS parameters of mean, minimum, and maximum values, the coefficient of variation of time-averaged WSS (TAWSSCV), and the maximum values of the oscillatory shear index (OSI) were calculated and compared in the curved proximal (M1) segments. Three cross-sectional planes were selected: the location perpendicular to the beginning of the long axis of the curved M1 segment of the MCA (proximal section), the most curved M1 location (curved M1 section), and the location before the insular (M2) segment bifurcation (distal section). The WSS and OSI parameters of the proximal, curved, and distal sections of the curved M1 segment were compared, including the inner and outer curvatures of the curved M1 section. Results: Of the curved M1 segments, the curved M1 section had significantly lower minimum TAWSS values than the proximal (P=0.031) and distal sections (P=0.002), and the curved M1 section had significantly higher maximum OSI values than the distal section (P=0.001). The TAWSSCV values at the curved M1 section were significantly higher than the proximal (P=0.001) and distal sections (P<0.001). At the curved M1 section, the inner curvature showed a significantly lower minimum TAWSS (P=0.013) and higher maximum OSI values (P=0.002) than the outer curvature. Conclusions: There are distribution variation of WSS and OSI parameters at the curved M1 section of the curved MCA, and the inner curvature of the curved M1 section has the lowest WSS and highest OSI distribution. The local hemodynamic features of the curved MCA may be related to the predilection for atherosclerotic plaque development.

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