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1.
Sensors (Basel) ; 24(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38474920

RESUMO

Many concepts for future generations of wireless communication systems use coherent processing of signals from many distributed antennas. The aim is to improve communication reliability, capacity, and energy efficiency and provide possibilities for new applications through integrated communication and sensing. The large bandwidths available in the higher bands have inspired much work regarding sensing in the millimeter-wave (mmWave) and sub-THz bands; however, the sub-6 GHz cellular bands will still be the main provider of wide cellular coverage due to the more favorable propagation conditions. In this paper, we present a measurement system and results of sub-6 GHz distributed multiple-input-multiple-output (MIMO) measurements performed in an industrial environment. From the measurements, we evaluated the diversity for both large-scale and small-scale fading and characterized the link reliability. We also analyzed the possibility of multistatic sensing and positioning of users in the environment, with the initial results showing a mean-square error below 20 cm on the estimated position. Further, the results clearly showed that new channel models are needed that are spatially consistent and deal with the nonstationary channel properties among the antennas.

2.
Acta Neurochir (Wien) ; 164(6): 1627-1634, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35001232

RESUMO

BACKGROUND: Severe intracranial atherosclerotic stenosis (ICAS) is a major cause of stroke. Although percutaneous transluminal angioplasty and stenting (PTAS) treatment methods have increased over the last decade as alternative therapies, there is debate regarding the best method of treatment, with medical and surgical therapies often suggested. METHODS: We analyzed the long-term follow-up results from 5 years of intracranial stenting for intracranial stenosis from three stroke centers. The primary endpoints were early stroke complications or death within 30 days after stent insertion, and the secondary endpoint was a recurrent stroke between 30 days and 60 months. Correlating factors and Kaplan-Meier survival curves for recurrent stroke and in-stent restenosis (ISR) were also obtained. RESULTS: Seventy-three PTAS in 71 patients were examined in this study. The primary and secondary endpoints were all 8.2% (n = 6), and restenosis was 13.7% (n = 10) during the 5-year follow-up. The primary endpoints were significantly frequent in the high National Institutes of Health Stroke Scale (NIHSS) and early stent (≤ 7 days after dual antiplatelet medication) groups. Secondary endpoint and ISR were identically frequent in the younger age group and in the presence of tandem stenosis in other major intracranial arteries. The cumulative probability of recurrent stroke and ISR at 60 months was 16.4% and 14.1%, respectively. CONCLUSIONS: This study shows that PTAS is safe and effective for major ICAS. Reducing the early complication rate is still an important factor, despite the fact that long-term stroke recurrence was low.


Assuntos
Arteriosclerose Intracraniana , Acidente Vascular Cerebral , Angioplastia/efeitos adversos , Constrição Patológica/diagnóstico por imagem , Constrição Patológica/cirurgia , Humanos , Arteriosclerose Intracraniana/diagnóstico por imagem , Arteriosclerose Intracraniana/cirurgia , Stents/efeitos adversos , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento , Estados Unidos
3.
Cardiovasc Diabetol ; 20(1): 114, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34044825

RESUMO

BACKGROUND: Carotid atherosclerosis represents one of the complications of diabetes mellitus. In particular, plaque instability contributes to disease progression and stroke incidence. High mobility group box-1 (HMGB1) is a nuclear protein involved in promotion and progression of atherosclerosis and cardiovascular diseases. The aim of this study was to analyze the relationship between HMGB1 serum levels, main inflammatory cytokines, the presence of internal carotid stenosis and unstable plaque in a diabetic population. RESEARCH DESIGN AND METHODS: We studied 873 diabetic patients, including 347 patients with internal carotid artery stenosis (ICAS) who underwent carotid endarterectomy and 526 diabetic patients without internal carotid artery stenosis (WICAS). At baseline, HMGB1 and the main inflammatory cytokines serum levels were evaluated. For ICAS patients, the histological features of carotid plaque were also collected to differentiate them in patients with stable or unstable atherosclerotic lesions. RESULTS: We found that HMGB1 serum levels, osteoprotegerin, high-sensitivity C-reactive protein, tumor necrosis factor-alpha and interleukin-6, were significantly higher in diabetic ICAS patients compared to diabetic WICAS patients. Among ICAS patients, individuals with unstable plaque had higher levels of these cytokines, compared to patients with stable plaque. A multivariable stepwise logistic regression analysis showed that HMGB1 and osteoprotegerin remained independently associated with unstable plaque in ICAS patients. CONCLUSIONS: The present study demonstrated that HMGB1 is an independent risk factor for carotid plaque vulnerability in an Italian population with diabetes mellitus, representing a promising biomarker of carotid plaque instability and a possible molecular target to treat unstable carotid plaques and to prevent stroke.


Assuntos
Estenose das Carótidas/sangue , Diabetes Mellitus Tipo 2/sangue , Proteína HMGB1/sangue , Placa Aterosclerótica , Idoso , Biomarcadores/sangue , Proteína C-Reativa/análise , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/epidemiologia , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Mediadores da Inflamação/metabolismo , Interleucina-6/sangue , Itália/epidemiologia , Masculino , Osteoprotegerina/sangue , Prognóstico , Medição de Risco , Fatores de Risco , Ruptura Espontânea , Fator de Necrose Tumoral alfa/sangue
4.
Eur Neurol ; 83(2): 162-166, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32460290

RESUMO

BACKGROUND: Intravenous thrombolysis (IVT) with urokinase is the standard reperfusion therapy for acute cerebral infarction (ACI) in China. Only about 30% patients who use urokinase for IVT can recanalize. Therefore, this study aimed to analyze the influencing factors of recanalization after IVT using urokinase in ACI patients. METHODS: A total of 391 consecutive patients with a diagnosis of ACI from January 2013 to October 2019 were enrolled and divided into 2 groups: patients without recanalization and patients with recanalization. Related data were collected and analyzed. RESULTS: Univariate analysis showed that there were significant differences in gender, atrial fibrillation, erythrocyte mean corpuscular volume, platelet large cell ratio (P-LCR), glucose (GLU), and severity of ICAS between patients without recanalization and patients with recanalization (p < 0.05). Multivariate logistic regression analysis indicated that P-LCR (odds ratio [OR] = 0.17, 95% confidence interval [CI] = 0.03-0.89, p = 0.04), GLU (OR = 0.28, 95% CI = 0.11-0.67, p = 0.004), and ICAS severity (OR = 0.48, 95% CI = 0.32-0.76, p = 0.001) were the influencing factors of recanalization. CONCLUSION: For patients with higher levels of P-LCR, GLU, or ICAS severity, the recanalization rate might decrease after ACI.


Assuntos
Infarto Cerebral/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Terapia Trombolítica/métodos , Ativador de Plasminogênio Tipo Uroquinase/uso terapêutico , Administração Intravenosa , Idoso , Glicemia , Plaquetas/patologia , Infarto Cerebral/fisiopatologia , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
5.
J Stroke Cerebrovasc Dis ; 29(12): 105254, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32992190

RESUMO

BACKGROUND: The safety and efficacy of dual antiplatelet use for symptomatic intracranial atherosclerosis beyond 90 days is unknown. Data from SAMMPRIS was used to determine if dual antiplatelet therapy (DAPT) beyond 90 days impacted the risk of ischemic stroke and hemorrhage. METHODS: This post hoc exploratory analysis from SAMMPRIS included patients who did not have a primary endpoint within 90 days after enrollment (n = 397). Patients in both the aggressive medical management (AMM) and percutaneous transluminal angioplasty and stenting (PTAS) arms were included. Baseline features and outcomes during follow-up were compared between patients who remained on DAPT beyond 90 days (on clopidogrel) and patients who discontinued clopidogrel and remained on aspirin alone at 90 days (off clopidogrel) using Fisher's exact tests. RESULTS: The stroke rate was numerically lower in the group on clopidogrel vs off clopidogrel among both the AMM alone arm (6.0% versus 10.8%, p = 0.31) and the PTAS arm (8.7% versus 9.8%; p = 0.82), but the difference was not significant. The major hemorrhage rates were numerically higher in the group on clopidogrel vs. off clopidogrel group among both the AMM alone arm (4.0% versus 2.5%; p = 0.67) and the PTAS arm (10.9% versus 3.5%; p = 0.08), but were not significant. CONCLUSION: This exploratory analysis suggests that prolonged DAPT use may lower the risk of stroke in medically treated patients with intracranial stenosis but may increase the risk of major hemorrhage.


Assuntos
Aspirina/administração & dosagem , Clopidogrel/administração & dosagem , Terapia Antiplaquetária Dupla , Arteriosclerose Intracraniana/tratamento farmacológico , Inibidores da Agregação Plaquetária/administração & dosagem , Idoso , Angioplastia/instrumentação , Aspirina/efeitos adversos , Clopidogrel/efeitos adversos , Esquema de Medicação , Terapia Antiplaquetária Dupla/efeitos adversos , Feminino , Hemorragia/induzido quimicamente , Humanos , Arteriosclerose Intracraniana/complicações , Arteriosclerose Intracraniana/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/efeitos adversos , Fatores de Risco , Stents , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Fatores de Tempo , Resultado do Tratamento
6.
J Cell Biochem ; 118(9): 2672-2683, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28098405

RESUMO

In the present study we focused on the improvisation of islet survival in hypoxia.The Islet like cell aggregates (ICAs) derived from wharton's jelly mesenchymal stem cells (WJ MSC) were cultured with and without WJ MSC for 48 h in hypoxia and normoxia and tested for their direct trophic effect on ß cell survival. The WJ MSCs themselves secreted insulin upon glucose challenge and expressed the pancreatic markers at both transcription and translational level (C-peptide, Insulin, Glucagon, and Glut 2). Direct contact of MSCs with ICAs facilitated highest viability under hypoxia as evidenced by fluorescein diacetate/propidium iodide and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The cytokine analysis of the co-cultured ICAs revealed amplification of anti-inflammatory cytokine like TGFß and TNFα accompanied by depletion of pro-inflammatory cytokines. The increment in VEGF and PDGFa was also seen showing their ability to vascularize upon transplantation. This was further accompanied by reduction in total reactive oxygen species, nitric oxide, and super oxide ions and down regulation of Caspase3, Caspase8, p53, and up regulation of Bcl2 confirming prevention of apoptosis in ICAs. The western blot analysis confirmed the cytoprotective effect of WJ MSC on ICAs as they enhanced the anti-apoptotic marker BCL2 and reduced the expression of apoptotic markers, Annexin 5 and Caspase 3. There was a significant reduction in the expression of p38 protein in the presence of MSCs making the ICAs responsive to glucose. Taken together our data demonstrate for the first time that the WJ MSC expressed pancreatic markers and their supplementation protected engineered islets against hypoxia and oxidative stress. J. Cell. Biochem. 118: 2672-2683, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Células Secretoras de Insulina/metabolismo , Células-Tronco Mesenquimais/metabolismo , Estresse Oxidativo , Anexinas/metabolismo , Caspase 3/metabolismo , Caspase 8/metabolismo , Hipóxia Celular , Sobrevivência Celular , Humanos , Células Secretoras de Insulina/citologia , Células-Tronco Mesenquimais/citologia , Fator de Crescimento Derivado de Plaquetas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
7.
Neurol Sci ; 37(10): 1645-51, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27365086

RESUMO

There are currently no data available on the prevalence of symptomatic intracranial atherosclerosis (ICAS) in Italy. The aim of this prospective, multicenter, hospital-based, transcranial ultrasound study was to establish the prevalence of ICAS among patients hospitalized with acute ischemic stroke. At 11 stroke centers across Italy, patients consecutively admitted for their first ever acute ischemic stroke were assessed prospectively over a 24-month period either with transcranial color-coded Doppler sonography (TCCS) or transcranial Doppler (TCD) according to validated criteria. ICAS was diagnosed when there was an evidence of a cerebral infarction in the territory of a ≥50 % stenosis detected by TCCS/TCD and confirmed by magnetic resonance angiography or computed tomography angiography. A total of 1134 patients were enrolled, 665 of them (58.6 %) men, with a mean age of 71.2 ± 13.3 years. ICAS was recorded in 99 patients (8.7 % of the whole sample, 8.9 % among Caucasians), most commonly located in the anterior circulation (63 of 99, 5.5 %). After adjusting for potential confounders, multivariate analysis identified carotid/vertebral ≥50 % stenosis [odds ratio (OR) 2.59, 95 % (confidence interval) CI 1.77-6.33; P = 0.02] and hypercholesterolemia (OR 1.38, 95 % CI 1.02-1.89; P = 0.02) as being independently associated with ICAS. ICAS is a surprisingly relevant cause of ischemic stroke in Italy, identified in almost 9 % of first-ever stroke patients. It is more prevalent in the anterior circulation and independently associated with hemodynamically significant cervical vessel atherosclerosis and hypercholesterolemia. These findings support the systematic use of transcranial ultrasound to identify ICAS in patients presenting with acute ischemic stroke and in cases with ≥50 % cervical vessel stenoses.


Assuntos
Arteriosclerose Intracraniana/diagnóstico por imagem , Arteriosclerose Intracraniana/epidemiologia , Ultrassonografia Doppler Transcraniana/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Itália/epidemiologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Análise Multivariada
8.
J Clin Neurosci ; 123: 137-147, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38574685

RESUMO

OBJECTIVE: This study aimed to analyze the risk factors for recurrent ischemic stroke in patients with symptomatic intracranial atherosclerotic stenosis (ICAS) who underwent successful stent placement and to establish a nomogram prediction model. METHODS: We utilized data from a prospective collection of 430 consecutive patients at Jining NO.1 People's Hospital from November 2021 to November 2022, conducting further analysis on the subset of 400 patients who met the inclusion criteria. They were further divided into training (n=321) and validation (n=79) groups. In the training group, we used univariate and multivariate COX regression to find independent risk factors for recurrent stroke and then created a nomogram. The assessment of the nomogram's discrimination and calibration was performed through the examination of various measures including the Consistency index (C-index), the area under the receiver operating characteristic (ROC) curves (AUC), and the calibration plots. Decision curve analysis (DCA) was used to evaluate the clinical utility of the nomogram by quantifying the net benefit to the patient under different threshold probabilities. RESULTS: The nomogram for predicting recurrent ischemic stroke in symptomatic ICAS patients after stent placement utilizes six variables: coronary heart disease (CHD), smoking, multiple ICAS, systolic blood pressure (SBP), in-stent restenosis (ISR), and fasting plasma glucose. The C-index (0.884 for the training cohort and 0.87 for the validation cohort) and the time-dependent AUC (>0.7) indicated satisfactory discriminative ability of the nomogram. Furthermore, DCA indicated a clinical net benefit from the nomogram. CONCLUSIONS: The predictive model constructed includes six predictive factors: CHD, smoking, multiple ICAS, SBP, ISR and fasting blood glucose. The model demonstrates good predictive ability and can be utilized to predict ischemic stroke recurrence in patients with symptomatic ICAS after successful stent placement.


Assuntos
Arteriosclerose Intracraniana , AVC Isquêmico , Nomogramas , Recidiva , Stents , Humanos , Masculino , Feminino , Arteriosclerose Intracraniana/cirurgia , Arteriosclerose Intracraniana/diagnóstico por imagem , Pessoa de Meia-Idade , AVC Isquêmico/cirurgia , AVC Isquêmico/etiologia , Idoso , Fatores de Risco , Estudos Prospectivos , Constrição Patológica/cirurgia
9.
Quant Imaging Med Surg ; 14(6): 3970-3982, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38846310

RESUMO

Background: The recent randomized controlled trials studying intracranial atherosclerotic stenosis (ICAS) have used digital subtraction angiography (DSA) to quantify stenosis and enroll patients. However, some disadvantages of DSA such as invasive features, contrast agent overuse, and X-ray radiation overexposure, were not considered in these studies. This study aimed to explore whether computed tomography angiography (CTA) with semi-automatic analysis could be an alternative method to DSA in quantifying the absolute stenotic degree in clinical trials. Methods: Patients with 50-99% ICAS were consecutively screened, prospectively enrolled, and underwent CTA and DSA between March 2021 and December 2021 at 6 centers. This study was registered at www.chictr.org.cn (ChiCTR2100052925). The absolute stenotic degree of ICAS on CTA with semi-automatic analysis was calculated by several protocols using minimal/maximum/mean diameters of stenosis and reference site from a semi-automatic analysis software. Intraclass correlation coefficient (ICC) was used to evaluate the reliabilities of quantifying stenotic degree on CTA. The optimal protocol for quantifying ICAS on CTA was explored. The agreements of quantifying ICAS in calcified or non-calcified lesions and 50-69% or 70-99% stenosis on CTA and DSA were assessed. Results: A total of 191 participants (58.8±10.7 years; 148 men) with 202 lesions were enrolled. The optimal protocol for quantifying ICAS on CTA was calculated as (1 - the minimal diameter of stenosis/the mean diameter of reference) × 100% for its highest agreement with DSA [ICC, 0.955, 95% confidence interval (CI): 0.944-0.966, P<0.001]. Among the 202 lesions, 80.2% (162/202) exhibited severe stenosis on DSA. The accuracy of CTA in detecting severe ICAS was excellent (sensitivity =95.1%, positive predictive value =98.1%). The agreements between DSA and CTA in non-calcified lesions (ICC, 0.960 vs. 0.849) and severe stenosis (ICC, 0.918 vs. 0.841) were higher than those in calcified lesions and moderate stenosis. Conclusions: CTA with semi-automatic analysis demonstrated an excellent agreement with DSA in quantifying ICAS, making it promising to replace DSA for the measurement of absolute stenotic degree in clinical trials.

10.
Sci Rep ; 14(1): 10765, 2024 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-38729973

RESUMO

The Shiga Epidemiological Study of Subclinical Atherosclerosis was conducted in Kusatsu City, Shiga, Japan, from 2006 to 2008. Participants were measured for LDL-p through nuclear magnetic resonance technology. 740 men participated in follow-up and underwent 1.5 T brain magnetic resonance angiography from 2012 to 2015. Participants were categorized as no-ICAS, and ICAS consisted of mild-ICAS (1 to < 50%) and severe-ICAS (≥ 50%) in any of the arteries examined. After exclusion criteria, 711 men left for analysis, we used multiple logistic regression to examine the association between lipid profiles and ICAS prevalence. Among the study participants, 205 individuals (28.8%) had ICAS, while 144 individuals (20.3%) demonstrated discordance between LDL-c and LDL-p levels. The discordance "low LDL-c-high LDL-p" group had the highest ICAS risk with an adjusted OR (95% CI) of 2.78 (1.55-5.00) in the reference of the concordance "low LDL-c-low LDL-p" group. This was followed by the concordance "high LDL-c-high LDL-p" group of 2.56 (1.69-3.85) and the discordance "high LDL-c-low LDL-p" group of 2.40 (1.29-4.46). These findings suggest that evaluating LDL-p levels alongside LDL-c may aid in identifying adults at a higher risk for ICAS.


Assuntos
Lipoproteínas LDL , Humanos , Masculino , Pessoa de Meia-Idade , Lipoproteínas LDL/sangue , Idoso , Japão/epidemiologia , Angiografia por Ressonância Magnética/métodos , Constrição Patológica/sangue , LDL-Colesterol/sangue , Lipídeos/sangue , Fatores de Risco , Adulto , Feminino
11.
Transl Stroke Res ; 14(2): 137-145, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35445969

RESUMO

Optical coherence tomography (OCT), based on the backscattering or reflection of near-infrared light, enables an ultra-high resolution of up to 10 µm. The successful application of OCT in coronary artery diseases has sparked increasing interest in its implementation in cerebrovascular diseases. OCT has shown promising potential in the atherosclerotic plaque structure characterization, plaque rupture risk stratification, pre-stenting and post-stenting evaluation, and long-term follow-up in extracranial and intracranial atherosclerotic stenosis (ICAS). In hemorrhagic cerebrovascular diseases, OCT plays an important role in the structure evaluation, rupture risk stratification, and healing and occlusion evaluation following initial treatment in intracranial aneurysms (IAs). In this study, we summarized the applications of OCT in the diagnosis, treatment, and follow-up of cerebrovascular diseases, especially in ICAS and IAs. The current limitations and future directions of OCT in the endovascular treatment of cerebrovascular diseases were also discussed.


Assuntos
Doença da Artéria Coronariana , Aneurisma Intracraniano , Placa Aterosclerótica , Doenças Vasculares , Humanos , Tomografia de Coerência Óptica/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/terapia , Stents , Doença da Artéria Coronariana/terapia
12.
J Neurosurg ; 139(3): 714-720, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36670537

RESUMO

OBJECTIVE: Despite advances in endovascular techniques, mechanical thrombectomy (MT) fails to achieve successful reperfusion in approximately 20% of patients. This study aimed to identify common etiologies and predictors of failed thrombectomy in a contemporary series. METHODS: A prospectively maintained database of MT patients between January 2013 and August 2021 was interrogated. Failed MT was defined as a final modified Thrombolysis in Cerebral Infarction score < 2b. Demographic data, procedural details, stroke etiology, and anatomical data in patients who underwent MT with subsequent failed reperfusion were collected. RESULTS: Of a total 1010 MT procedures, 120 (11.9%) were unsuccessful. The mean patient age was 66.8 years; 51.5% of patients were male, and 61.1% were White. The most common failure location was intracranial (93.3%) followed by failure at the arch (3.3%) and neck (3.3%). Among patients with intracranial failure, underlying intracranial atherosclerosis (ICAS) was the cause of failure in 84 patients (70%). Compared with patients with successful MT, patients with failed MT had a longer onset to puncture time (p = 0.012) and onset to groin time (p = 0.04). Rescue stenting was performed in 45 cases: 39 patients (4.4%) with successful MT and 6 (5.0%) with MT failure (p = 0.765). Multivariate analysis demonstrated that diabetes mellitus (p = 0.009) was independently associated with unsuccessful reperfusion. CONCLUSIONS: Failed MT was encountered in approximately 12% of MT procedures. The most common cause of failed MT was underlying ICAS. Further studies to evaluate better ways of early identification and treatment of ICAS-related large-vessel occlusion are warranted.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , Acidente Vascular Cerebral , Humanos , Masculino , Idoso , Feminino , Prevalência , Resultado do Tratamento , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/terapia , Trombectomia/métodos , Procedimentos Endovasculares/métodos , Estudos Retrospectivos , Stents/efeitos adversos , Isquemia Encefálica/epidemiologia , Isquemia Encefálica/etiologia , Isquemia Encefálica/terapia
13.
Quant Imaging Med Surg ; 13(2): 1048-1057, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36819235

RESUMO

Background: Hyperperfusion syndrome (HPS) is a serious complication after stent implantation in symptomatic intracranial atherosclerotic stenosis (ICAS). This study aims to explore the predictive value of preprocedural computed tomography perfusion (CTP) for HPS after intracranial stenting. Methods: In this retrospective case-control study we collected data from consecutive patients from June 2012 to September 2019 who underwent stent implantation due to severe symptomatic ICAS. Patients who underwent CTP before the procedure were enrolled. CTP was postprocessed using the automated RAPID software to assess the preoperative cerebral perfusion. According to the presence or absence of HPS, the patients were classified into two groups: the HPS group and the non-HPS group. The baseline data, lesion characteristics, and preoperative CTP parameters between the two groups were compared. The receiver operating characteristic (ROC) curve analysis was performed to determine the optimal predictor of HPS. Results: Among the 170 eligible patients, 6 patients (3.53%) had HPS, including 3 who presented with intracranial hemorrhages (ICHs), 1 who had dysphoria, 1 who had delirium, and 1 who had a headache. There were no significant differences in baseline and lesion characteristics between the HPS and non-HPS groups. Compared with the non-HPS group, the HPS group had a significantly higher volume of time-to-maximum (Tmax) >4 s (429.5 vs. 93 mL; P=0.006) and Tmax >6 s (200 vs. 0 mL; P=0.003). The optimal volume threshold for maximizing sensitivity in predicting HPS was 65.5 mL with Tmax >4 s [area under the curve (AUC), 0.832; 95% confidence interval (CI): 0.650 to 1.000; P=0.006]. Conclusions: Tmax >4 s volume may be a predictor of HPS after stent implantation in symptomatic ICAS. Further prospective studies should be conducted to confirm our conclusion.

14.
J Clin Med ; 12(4)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36835954

RESUMO

Asian children are increasingly being diagnosed with type 1 diabetes (T1D) or type 2 diabetes (T2D), and the presence of coexisting islet autoimmune antibodies complicate diagnosis. Here, we aimed to determine the prevalence of islet cell autoantibodies (ICAs) and glutamic acid decarboxylase 65 autoantibodies (GADAs) in children with T1D versus T2D living in Vietnam. This cross-sectional study included 145 pediatric patients aged 10.3 ± 3.6 years, with 53.1% and 46.9% having T1D and T2D, respectively. ICAs were reported in only 3.9% of pediatric T1Ds, which was not significantly different from the 1.5% of those with T2D. Older children with T1D were positive for either ICAs, or ICAs and GADAs (5-9 and 10-15 years), whereas only a small proportion of children aged 0-4 years were positive for GADAs (18%). Notably, 27.9% of children with T2D aged 10-15 were positive for GADAs, and all were classified as overweight (n = 9) or obese (n = 10). GADAs were more commonly observed in T1D patients younger than four years than ICAs, which were more prevalent in older children (5-15 years). Even though few children with T2D carried ICAs and GADAs, finding a better biomarker or an appropriate time to confirm diabetes type may require further investigation.

15.
Quant Imaging Med Surg ; 13(4): 2514-2525, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37064395

RESUMO

Background: The assessment of cerebral blood flow (CBF) is crucial in the evaluation of intracranial atherosclerotic disease. This study was performed to compare single postlabeling delay (PLD) 3-dimensional pseudo-continuous arterial spin labeling (3D-pCASL) and 7-delay 3D-pCASL magnetic resonance imaging in patients with intracranial atherosclerotic stenosis. Methods: A total of 26 patients with moderate to severe atherosclerotic stenosis or occlusion of an intracranial artery were prospectively enrolled in the study. Perfusion parameters were obtained in various regions of interest (ROIs), namely CBF for single PLDs of 1,525 ms (CBF1525 ms), 2,025 ms (CBF2025 ms), and 2,525 ms (CBF2525 ms) with 3D-pCASL, as well as arterial transit time (ATT) and transit-corrected CBF (CBFtransit-corrected) for 7-delay 3D-pCASL. The consistency of the perfusion parameters between single-PLD 3D-pCASL and 7-delay 3D-pCASL was investigated, and the relationship between vascular stenosis and perfusion parameters was explored. Results: Bland-Altman plots compared the CBF values derived from single-PLD 3D-pCASL to those from CBFtransit-corrected. ATT significantly correlated with the difference between CBFtransit-corrected and CBF1525 ms, CBF2025 ms, and CBF2525 ms, respectively (P<0.05). Binary logistic regression analysis revealed that the CBFtransit-corrected and ATT correlated with the presence of moderate or more severe stenotic vascular territories (P<0.05). Conclusions: The single-PLD 3D-pCASL and the 7-delay 3D-pCASL showed inconsistencies in the assessment of CBF, and the perfusion parameters generated under the standard single-PLD 3D-pCASL were more affected by ATT. Moreover, CBFtransit-corrected and ATT were consistent with stenotic vascular territories, which is useful in the evaluation of intracranial atherosclerotic disease.

16.
Brain Behav ; 13(6): e3036, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37128146

RESUMO

BACKGROUND: Nonvalvular atrial fibrillation (NVAF) and intracranial atherosclerotic stenosis (ICAS) are major causes of ischemic stroke. Relatively few studies have focused on the risk factors and clinical features of ischemic stroke caused by NVAF combined with ICAS. METHOD: We retrospectively evaluated NVAF and/or ICAS in patients with acute ischemic stroke admitted within 72 h after stroke. All patients with acute ischemic stroke underwent diffusion-weighted magnetic resonance imaging (DWI), magnetic resonance angiography (MRA), computed tomography angiography (CTA), and/or digital subtraction angiography (DSA). NVAF was detected by routine electrocardiogram or 24-h Holter examination, Doppler echocardiography, and contrast echocardiography of the right heart. RESULTS: Among the 635 enrolled patients, NVAF, ICAS, and NVAF+ICAS were diagnosed in 170 (26.77%), 255 (40.16%), and 210 (33.07%) patients, respectively. Patients in the NVAF+ICAS group were older (p < .001), specifically aged ≥75 years (p < .001). The admission time of the NVAF+ICAS group was shorter (p < .001) than that of the ICAS group. The admission NIHSS score of the NVAF group was higher than that of the NVAF+ICAS group (p < .001). HsCRP, NTpro-BNP, and LEVF levels were significantly different among the three groups (p < .001). NVAF+ICAS ischemic stroke occurred mainly in the right hemisphere (52.4%). CONCLUSION: NVAF with ICAS ischemic stroke is more likely to occur in older patients. Infarctions occurred mainly in the right cerebral hemisphere. Neurological deficits in NVAF are more severe than those in NVAF combined with ICAS and in simple ICAS ischemic strokes. HsCRP, LEVF, andNTpro-BNP seem to be closely associated with NVAF+ICAS ischemic stroke.


Assuntos
Fibrilação Atrial , Arteriosclerose Intracraniana , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Idoso , AVC Isquêmico/complicações , AVC Isquêmico/diagnóstico por imagem , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico por imagem , Proteína C-Reativa , Estudos Retrospectivos , Constrição Patológica/complicações , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Fatores de Risco , Arteriosclerose Intracraniana/complicações , Arteriosclerose Intracraniana/diagnóstico por imagem
17.
Heliyon ; 9(2): e13527, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36852079

RESUMO

Background: Fractional flow reserve is widely used for the functional evaluation of coronary artery stenosis. Some studies have similarly used the translesional pressure ratio measurements for the functional evaluation of intracranial atherosclerotic stenosis. In this paper, we aimed to investigate the relationship between pressure ratio and cerebral tissue perfusion by MR perfusion imaging and provided a non-invasive method for evaluating the functional significance of intracranial atherosclerotic stenosis. Methods: A total of 18 consecutive patients with intracranial atherosclerotic stenosis patients including 19 stenotic vessels were recruited. The pressure was measured using a pressure guidewire, the pressure ratio before and after the endovascular intervention was calculated and compared with the severity of diameter stenosis and perfusion-derived MR (the time to maximum tissure residue function (Tmax)). Moreover, the DSA-derived pressure ratio was computed using a novel computational fluid dynamics-based model, termed CFD-PR, and was compared with the actual pressure ratio to assess its diagnostic accuracy. Results: The pressure ratio increased after percutaneous transluminal angioplasty or stenting, while the correlation between pressure ratio and diameter stenosis was not significant. The pressure ratio was negatively correlated with Tmax (r = -0.73, P < 0.01), and a 95% confidence interval for the cutoff value of pressure ratio = 0.67 (95% confidence interval: 0.58-0.76) was suggested. There was a good correlation (mean = 0.02, Spearman's correlation coefficient r = 0.908, P < 0.001) and agreement (limits of agreement: -0.157 to 0.196, P = 0.954) between CFD-PR and the actual pressure ratio. Conclusions: This exploratory study indicates the pressure ratio may correlate with the perfusion status. The pressure ratio can be calculated through a non-invasive method using a computational fluid dynamics-based method.

18.
Ann Transl Med ; 10(16): 909, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36111049

RESUMO

Background: Intracranial atherosclerotic stenosis (ICAS) is one of the leading causes of stroke worldwide. Current diagnostic evaluations and treatments remain insufficient to assess the vulnerability of intracranial plaques and reduce the recurrence of stroke in symptomatic ICAS. On the other hand, asymptomatic ICAS is associated with an increased risk of cognitive impairment. The pathogenesis of ICAS related cognitive decline is largely unknown. The aim of SICO-ICAS study (stroke incidence and cognitive outcomes of ICAS) is to elucidate the pathophysiology of stroke and cognitive impairment in ICAS population, comprehensively evaluating the complex interactions among life-course exposure, genomic variation, vascular risk factors, cerebrovascular burden and coexisting neurodegeneration. Methods: SICO-ICAS is a multicenter, prospective, observational cohort study. We aim to recruit 3,000 patients with symptomatic or asymptomatic ICAS (>50% or occlusion) who will be followed up for ≥12 months. All participants will undergo pre-designed magnetic resonance imaging packages, blood biomarkers testing, as well as detailed cognitive domains assessment. All participants will undergo clinical visits every 6 months and telephone interviews every 3 months. The primary outcome measurement is ischemic stroke or cognitive impairment within 12 months after enrollment. Discussion: This study will establish a large prospective ICAS cohort, hopefully discover new biomarkers associated with vulnerable intracranial plaques, identify subjects at high risk for incident ischemic stroke or cognitive impairment, and eventually propose a precise diagnostic and treatment strategy for ICAS population. Trial Registration: Chinese Clinical Trials Register ChiCTR2200061938.

19.
J Neurosci Rural Pract ; 13(4): 775-777, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36743748

RESUMO

Intracranial atherosclerotic stenosis (ICAS) can cause ischemic stroke, up to 30-50% stroke in Asian population. However, recurrent exercise-induced headache due to ICAS has not been reported. We present a case of a patient 60-year-old male suffering from recurrent headache during exercise due to severe ICAS. The headache occurred after 5 minutes of running, appeared shortly after every running, and resolved at rest. Head magnetic resonance angiography showed moderate bilateral stenosis at middle cerebral artery (MCA), and cerebral catheter angiography confirmed 70% stenosis of the left MCA and 20% stenosis of the right MCA, with robust antegrade flow and good collaterals which explained why there was no neurological deficit. After treated with best medical therapy, including dual antiplatelet, statin therapy, and risk factor modification, for 90 days, he was capable of running for 20 min without headache.

20.
Front Neurol ; 13: 1004536, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36212635

RESUMO

Background and purpose: To explore the safety of endovascular therapy for concomitant non-adjacent unruptured intracranial aneurysms (UIAs) which is incidentally found in severe patients with symptomatic intracranial atherosclerotic stenosis at the same session and different sessions. Methods: Patients between January 2019 to December 2020 were retrospectively reviewed at our institution. Patients with concomitant non-adjacent incidental UIA in severe symptomatic intracranial atherosclerotic stenosis, who underwent endovascular treatment for both lesions were included. They were divided into two groups according to the intervals (The aneurysm was treated at the same session as stenosis or at separated sessions). The demographics, procedure details, complications, and clinical outcomes were compared between groups. Results: A total of 22 patients were involved. In total, ten patients underwent endovascular treatment for UIA and stenosis at one session and 12 patients at separate sessions. In total, three (13.6%) patients experienced procedural related complications, including 2 (20%) in the one session group and 1(8.3%) in the separate sessions group. Follow-up (Range 6-12, mean = 8.5 months) results showed good clinical outcome in all the patients. There is no statistical significance in terms of complication rate and unfavorable clinical outcome between groups. Conclusions: Non-adjacent concomitant UIA and severe symptomatic intracranial atherosclerotic stenosis will not pose additional endovascular treatment risks. Both simultaneous endovascular management and short intervals between separated procedures are technically feasible and safe.

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