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1.
BMC Geriatr ; 24(1): 545, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38914987

RESUMO

BACKGROUND: Late-life depression (LLD) is a prevalent neuropsychiatric disorder in the older population. While LLD exhibits high mortality rates, depressive symptoms in older adults are often masked by physical health conditions. In younger adults, depression is associated with deficits in pupil light reflex and eye blink rate, suggesting the potential use of these responses as biomarkers for LLD. METHODS: We conducted a study using video-based eye-tracking to investigate pupil and blink responses in LLD patients (n = 25), older (OLD) healthy controls (n = 29), and younger (YOUNG) healthy controls (n = 25). The aim was to determine whether there were alterations in pupil and blink responses in LLD compared to both OLD and YOUNG groups. RESULTS: LLD patients displayed significantly higher blink rates and dampened pupil constriction responses compared to OLD and YOUNG controls. While tonic pupil size in YOUNG differed from that of OLD, LLD patients did not exhibit a significant difference compared to OLD and YOUNG controls. GDS-15 scores in older adults correlated with light and darkness reflex response variability and blink rates. PHQ-15 scores showed a correlation with blink rates, while MoCA scores correlated with tonic pupil sizes. CONCLUSIONS: The findings demonstrate that LLD patients display altered pupil and blink behavior compared to OLD and YOUNG controls. These altered responses correlated differently with the severity of depressive, somatic, and cognitive symptoms, indicating their potential as objective biomarkers for LLD.


Assuntos
Piscadela , Depressão , Reflexo Pupilar , Humanos , Masculino , Idoso , Feminino , Piscadela/fisiologia , Reflexo Pupilar/fisiologia , Depressão/fisiopatologia , Depressão/psicologia , Idoso de 80 Anos ou mais , Pessoa de Meia-Idade , Adulto , Pupila/fisiologia , Escuridão , Adulto Jovem , Luz
2.
Acta Neurol Taiwan ; 32(3): 108-112, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37674421

RESUMO

PURPOSE: Warfarin is associated with paradoxical procoagulant effect that leads to a transient hypercoagulable state and acute ischemic stroke (AIS). This clinical dilemma is further confounded when the patient has multiple comorbidities and the optimal treatment strategies are unclear. CASE REPORT: We report a 78-year-old male with valvular heart disease, congestive heart failure, and atrial fibrillation, who received bioprosthetic valve replacement and developed AIS related to the paradoxical procoagulant effect of warfarin. Emergent cerebral angiography with mechanical thrombectomy was performed, and recanalization was successfully achieved. After shifting warfarin to nonvitamin K oral anticoagulant (NOAC), the paradoxical procoagulant effect ameliorated. CONCLUSION: This report describes the roles of endovascular therapy and NOAC in patients with similar highly complex conditions and has clinical relevance for therapeutic plans in the clinical setting.


Assuntos
Fibrilação Atrial , AVC Isquêmico , Masculino , Humanos , Idoso , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/cirurgia , Varfarina/efeitos adversos , Anticoagulantes/efeitos adversos , Trombectomia/efeitos adversos
3.
Neuroimage ; 233: 117955, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33716155

RESUMO

Cerebrovascular reactivity (CVR) reflects the capacity of the brain to meet changing physiological demands and can predict the risk of cerebrovascular diseases. CVR can be obtained by measuring the change in cerebral blood flow (CBF) during a brain stress test where CBF is altered by a vasodilator such as acetazolamide. Although the gold standard to quantify CBF is PET imaging, the procedure is invasive and inaccessible to most patients. Arterial spin labeling (ASL) is a non-invasive and quantitative MRI method to measure CBF, and a consensus guideline has been published for the clinical application of ASL. Despite single post labeling delay (PLD) pseudo-continuous ASL (PCASL) being the recommended ASL technique for CBF quantification, it is sensitive to variations to the arterial transit time (ATT) and labeling efficiency induced by the vasodilator in CVR studies. Multi-PLD ASL controls for the changes in ATT, and velocity selective ASL is in theory insensitive to both ATT and labeling efficiency. Here we investigate CVR using simultaneous 15O-water PET and ASL MRI data from 19 healthy subjects. CVR and CBF measured by the ASL techniques were compared using PET as the reference technique. The impacts of blood T1 and labeling efficiency on ASL were assessed using individual measurements of hematocrit and flow velocity data of the carotid and vertebral arteries measured using phase-contrast MRI. We found that multi-PLD PCASL is the ASL technique most consistent with PET for CVR quantification (group mean CVR of the whole brain = 42±19% and 40±18% respectively). Single-PLD ASL underestimated the CVR of the whole brain significantly by 15±10% compared with PET (p<0.01, paired t-test). Changes in ATT pre- and post-acetazolamide was the principal factor affecting ASL-based CVR quantification. Variations in labeling efficiency and blood T1 had negligible effects.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Encéfalo/metabolismo , Transtornos Cerebrovasculares/metabolismo , Imageamento por Ressonância Magnética/normas , Tomografia por Emissão de Pósitrons/normas , Marcadores de Spin , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Transtornos Cerebrovasculares/diagnóstico por imagem , Feminino , Hematócrito/métodos , Hematócrito/normas , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Radioisótopos de Oxigênio/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Fatores de Tempo , Água/metabolismo
4.
Eur Neurol ; 80(5-6): 335-340, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30928974

RESUMO

OBJECTIVES: The motor symptoms of Parkinson's disease (PD) vary among patients and have been categorized into 3 subtypes: tremor dominant, akinetic rigidity, and postural instability and gait disturbance (PIGD). Cerebral microbleed (CMB) is prevalent in people with PD and is associated with some nonmotor symptoms. The present study investigated the association between CMB and the motor subtypes of PD. MATERIALS AND METHODS: From 2009 to 2017, medical records and brain magnetic resonance imaging (MRI) reports of 134 Taiwanese people with early- and mid-stage PD were reviewed. CMBs were quantified according to the Microbleed Anatomical Rating Scale through susceptibility-weighted MRI. Motor subtypes were determined by medical chart review. Student's t test and multivariable logistic regression were used to analyze the association between the motor subtypes and CMB. Statistical analyses were performed using SPSS 19.0. RESULTS: Overall, 72 (53.7%) participants were women with a mean age of 69.5 ± 9.8 years. The prevalence of CMB was 33.6%, and lobar, deep, and infratentorial CMBs comprised 21.6, 19.4, and 11.9% of cases, respectively. PIGD subtype PD was associated with a significantly higher prevalence of any CMB as well as deep or lobar CMB. After adjustment for age and sex, the PIGD subtype was significantly positively associated with the presence of any, deep, and white matter (WM) and thalamic CMB. CONCLUSIONS: CMB was prevalent in Taiwanese people with early- and mid-stage PD, especially the PIGD subtype. Deep, especially thalamic and WM, CMBs exhibited the highest association with the PIGD subtype.


Assuntos
Hemorragia Cerebral/complicações , Doença de Parkinson/complicações , Idoso , Hemorragia Cerebral/epidemiologia , Feminino , Transtornos Neurológicos da Marcha/etiologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Equilíbrio Postural/fisiologia , Prevalência
5.
Neuroradiology ; 59(8): 791-796, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28689257

RESUMO

PURPOSE: No reliable imaging sign predicting cerebral hyperperfusion after intracranial arterial stenting (IAS) had been described in the literature. This study evaluated the effect of fluid-attenuated inversion recovery vascular hyperintensities (FVHs), also called hyperintense vessel sign on T2-weighted fluid-attenuated inversion recovery (T2-FLAIR) MR images, in predicting significant increase in cerebral blood flow (CBF) defined by arterial spin labeling (ASL) after IAS. METHODS: We reviewed ASL CBF images and T2-FLAIR MR images before (D0), 1 day after (D1), and 3 days after (D3) IAS of 16 patients. T1-weighted MR images were used as cerebral maps for calculating CBF. The changes in CBF values after IAS were calculated in and compared among stenting and nonstenting vascular territories. An increase more than 50% of CBF was considered as hyperperfusion. The effect of FVHs in predicting hyperperfusion was calculated. RESULTS: The D1 CBF value was significantly higher than the D0 CBF value in stenting vascular, contralateral anterior cerebral artery, contralateral middle cerebral artery, and contralateral posterior cerebral artery (PCA) territories (all P < .05). The D1 and D3 CBF values were significantly higher than the D0 CBF value in overall vascular (P < .001), overall nonstenting vascular (P < .001), and ipsilateral PCA (P < .05) territories. The rate of more than 50% increases in CBF was significantly higher in patients who exhibited asymmetric FVHs than in those who did not exhibit these findings. CONCLUSION: FVHs could be a critical predictor of a significant increase in CBF after IAS.


Assuntos
Angioplastia com Balão , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/terapia , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Infarto da Artéria Cerebral Média/terapia , Angiografia por Ressonância Magnética/métodos , Stents , Idoso , Anticoagulantes/administração & dosagem , Circulação Cerebrovascular , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Marcadores de Spin , Resultado do Tratamento
6.
Radiology ; 278(3): 854-62, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26439705

RESUMO

PURPOSE: To evaluate the age effect on working memory (WM) performance and functional activation after mild traumatic brain injury (MTBI). MATERIALS AND METHODS: This study was approved by the local research ethics committee. All participants provided written informed consent. N-back WM cerebral activation was assessed with functional magnetic resonance (MR) imaging in 13 younger (mean age, 26.2 years ± 2.9; range, 21-30 years) and 13 older (mean age, 57.8 years ± 6.6; range, 51-68 years) patients with MTBI and 26 age- and sex-matched control subjects. Two functional MR images were obtained within 1 month after injury and 6 weeks after the initial study. Group comparison and regression analysis were performed among postconcussion symptoms, neuropsychologic tests, and WM activity in both groups. RESULTS: In younger patients, initial hyperactivation was seen in the right precuneus and right inferior parietal gyrus (P = .047 and P = .025, respectively) in two-back greater than one-back conditions compared with younger control subjects, whereas in older patients, hypoactivation was seen in the right precuneus and right inferior frontal gyrus (P = .013 and P =.019, respectively) compared with older control subjects. Increased WM activity was associated with increased postconcussion symptoms in the right precuneus (r = 0.57; P = .026) and right inferior frontal gyrus (r = 0.60; P = .019) and poor WM performance in the right precuneus (r = -0.55; P = .027) in younger patients at initial studies but not in older patients. At follow-up examinations, partial recovery of activation pattern and decreased postconcussion symptoms (P = .04) were observed in younger patients but not in older patients. CONCLUSION: The different manifestations of postconcussion symptoms at functional MR imaging between younger and older patients confirmed the important role of age in the activation, modulation, and allocation of WM processing resources after MTBI. These findings also supported that younger patients have better neural plasticity and clinical recovery than do older patients.


Assuntos
Lesões Encefálicas/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Memória de Curto Prazo/fisiologia , Adulto , Fatores Etários , Idoso , Imagem Ecoplanar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
7.
Radiology ; 276(3): 828-35, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25919663

RESUMO

PURPOSE: To evaluate sex differences in mild traumatic brain injury (MTBI) with working memory functional magnetic resonance (MR) imaging. MATERIALS AND METHODS: Research ethics committee approval and patient written informed consent were obtained. Working memory brain activation patterns were assessed with functional MR imaging in 30 patients (15 consecutive men and 15 consecutive women) with MTBI and 30 control subjects (15 consecutive men and 15 consecutive women). Two imaging studies were performed in patients: the initial study, which was performed within 1 month after the injury, and a follow-up study, which was performed 6 weeks after the first study. For each participant, digit span and continuous performance testing were performed before functional MR imaging. Clinical data were analyzed by using Kruskal-Wallis, Mann-Whitney U, Wilcoxon signed rank, and Fisher exact tests. Within- and between-group differences of functional MR imaging data were analyzed with one- and two-sample t tests, respectively. RESULTS: Among female participants, the total digit span score was lower in the MTBI group than in the control group (P = .044). In initial working memory functional MR imaging studies, hyperactivation was found in the male MTBI group and hypoactivation was found in the female MTBI group compared with control male and female groups, respectively. At the 6-week follow-up study, the female MTBI group showed persistent hypoactivation, whereas the male MTBI group showed a regression of hyperactivation at visual comparison of activation maps. The male MTBI group was also found to have a higher initial ß value than the male control group (P = .040), and there was no significant difference between the male MTBI group and the male control group (P = .221) at follow-up evaluation, which was comparable to findings on activation maps. In the female MTBI group, average ß values at both initial and follow-up studies were lower compared with those in the female control group but were not statistically significant (P = .663 and P = .191, respectively). CONCLUSION: Female patients with MTBI had lower digit span scores than did female control subjects, and functional MR imaging depicted sex differences in working memory functional activation; hypoactivation with nonrecovery of activation change at follow-up studies may suggest a worse working memory outcome in female patients with MTBI.


Assuntos
Lesões Encefálicas/diagnóstico , Lesões Encefálicas/psicologia , Imageamento por Ressonância Magnética , Memória de Curto Prazo , Fatores Sexuais , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
8.
J Pain ; 25(4): 934-945, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37866648

RESUMO

An altered brain-gut axis is suspected to be one of the pathomechanisms in fibromyalgia (FM). This cross-sectional study investigated the associations among altered microbiota, psychological distress, and brain functional connectivity (FC) in FM. We recruited 25 FM patients and 25 healthy people in the present study. Psychological distress was measured using standardized questionnaires. Microbiota analysis was performed on the participants' stools. Functional magnetic resonance imaging data were acquired, and seed-based resting-state FC (rs-FC) analysis was conducted with the salience network nodes as seeds. Linear regression and mediation analyses evaluated microbiota, symptoms, and rs-FCs associations. We found altered microbiota diversity in FM, of which Phascolarctobacterium and Lachnoclostridium taxa increased the most and Faecalibacterium taxon decreased the most compared to controls. The Phascolarctobacterium abundance significantly predicted Beck depression inventory (BDI-II) scores in FM (ß = 6.83; P = .033). Rs-FCs from salience network nodes were reduced in FM, of which rs-FCs from the right lateral rostral prefrontal cortex (RPFC) to the lateral occipital cortex, superior division right (RPFC-sLOC) could be predicted by BDI-II scores in patients (ß = -.0064; P = .0054). In addition, the BDI-II score was a mediator in the association between Phascolarctobacterium abundance and rs-FCs of RPFC-sLOC (ab = -.06; 95% CI: -.16 to -9.10-3). In conclusion, microbial dysbiosis might be associated with altered neural networks mediated by psychological distress in FM, emphasizing the critical role of the brain-gut axis in FM's non-pain symptoms and supporting further analysis of mechanism-targeted therapies to reduce FM symptoms. PERSPECTIVE: Our study suggests microbial dysbiosis might be associated with psychological distress and the altered salience network, supporting the role of brain-gut axis dysfunction in fibromyalgia pathomechanisms. Further targeting therapies for microbial dysbiosis should be investigated to manage fibromyalgia patients in the future.


Assuntos
Fibromialgia , Angústia Psicológica , Humanos , Fibromialgia/diagnóstico por imagem , Fibromialgia/complicações , Eixo Encéfalo-Intestino , Estudos Transversais , Disbiose , Imageamento por Ressonância Magnética , Encéfalo
9.
J Rheumatol ; 50(8): 1063-1070, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37127319

RESUMO

OBJECTIVE: Abnormal functional connectivity (FC) and structure in the brain are found in patients with fibromyalgia (FM). This study investigated FC and structural alterations of the visual cortical system, the emerging contributor to pain processing, in patients with FM. METHODS: Thirty pain-free participants and 26 patients with FM were enrolled. Clinical characteristics were evaluated using standardized scales. Structural and resting-state functional magnetic resonance imaging were conducted. Seed-based FC analyses, voxel-based morphometry, and surface-based morphometry were performed. The FC and cortical structure of the visual system were compared between the 2 groups. The correlation between functional and structural changes in the visual cortical system with clinical presentation in the FM group was analyzed. RESULTS: The patients with FM showed increased FCs within visual networks, of which the FC between the visual medial network and the right lingual gyrus (LG) was positively correlated with the Fibromyalgia Impact Questionnaire (FIQ) score. However, the FM group showed decreased FCs from the visual occipital network (VON) to several regions, of which the FCs from the VON to the bilateral frontal orbital cortices were negatively correlated with the FIQ and Pittsburgh Sleep Quality Index scores. Cortical thickness of the lateral occipital cortex, LG, and pericalcarine in FM tended to increase. CONCLUSION: Altered FCs and structure in the visual cortical system might be involved in the pathomechanisms and clinical presentation in FM. These findings could potentially support further studies that seek to find diagnostic methods and mechanism-based therapies in patients with FM.


Assuntos
Fibromialgia , Humanos , Fibromialgia/patologia , Imageamento por Ressonância Magnética/métodos , Encéfalo , Dor
10.
Sci Rep ; 13(1): 404, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36624122

RESUMO

Automated ischemic stroke detection and classification according to its vascular territory is an essential step in stroke image evaluation, especially at hyperacute stage where mechanical thrombectomy may improve patients' outcome. This study aimed to evaluate the performance of various convolutional neural network (CNN) models on hyperacute staged diffusion-weighted images (DWI) for detection of ischemic stroke and classification into anterior circulation infarct (ACI), posterior circulation infarct (PCI) and normal image slices. In this retrospective study, 253 cases of hyperacute staged DWI were identified, downloaded and reviewed. After exclusion, DWI from 127 cases were used and we created a dataset containing total of 2119 image slices, and separates it into three groups, namely ACI (618 slices), PCI (149 slices) and normal (1352 slices). Two transfer learning based CNN models, namely Inception-v3, EfficientNet-b0 and one self-derived modified LeNet model were used. The performance of the models was evaluated and activation maps using gradient-weighted class activation mapping (Grad-Cam) technique were made. Inception-v3 had the best overall accuracy (86.3%), weighted F1 score (86.2%) and kappa score (0.715), followed by the modified LeNet (85.2% accuracy, 84.7% weighted F1 score and 0.693 kappa score). The EfficientNet-b0 had the poorest performance of 83.6% accuracy, 83% weighted F1 score and 0.662 kappa score. The activation map showed that one possible explanation for misclassification is due to susceptibility artifact. A sufficiently high performance can be achieved by using CNN model to detect ischemic stroke on hyperacute staged DWI and classify it according to vascular territory.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Isquemia Encefálica/diagnóstico por imagem , AVC Isquêmico/diagnóstico por imagem , Estudos Retrospectivos , Imagem de Difusão por Ressonância Magnética/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Redes Neurais de Computação , Infarto
11.
Biomedicines ; 10(12)2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36551758

RESUMO

Abnormal resting-state functional connectivity (rs-FC) and brain structure have emerged as pathological hallmarks of fibromyalgia (FM). This study investigated and compared the accuracy of network rs-FC and brain structural features in identifying FM with a machine learning (ML) approach. Twenty-six FM patients and thirty healthy controls were recruited. Clinical presentation was measured by questionnaires. After MRI acquisitions, network rs-FC z-score and network-based gray matter volume matrices were exacted and preprocessed. The performance of feature selection and classification methods was measured. Correlation analyses between predictive features in final models and clinical data were performed. The combination of the recursive feature elimination (RFE) selection method and support vector machine (rs-FC data) or logistic regression (structural data), after permutation importance feature selection, showed high performance in distinguishing FM patients from pain-free controls, in which the rs-FC ML model outperformed the structural ML model (accuracy: 0.91 vs. 0.86, AUC: 0.93 vs. 0.88). The combined rs-FC and structural ML model showed the best performance (accuracy: 0.95, AUC: 0.95). Additionally, several rs-FC features in the final ML model correlated with FM's clinical data. In conclusion, ML models based on rs-FC and brain structural MRI features could effectively differentiate FM patients from pain-free subjects.

12.
J Cereb Blood Flow Metab ; 42(8): 1493-1506, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35236136

RESUMO

Cerebrovascular reactivity (CVR) reflects the CBF change to meet different physiological demands. The reference CVR technique is PET imaging with vasodilators but is inaccessible to most patients. DSC can measure transit time to evaluate patients suspected of stroke, but the use of gadolinium may cause side-effects. Arterial spin labeling (ASL) is a non-invasive MRI technique for CBF measurements. Here, we investigate the effectiveness of ASL with single and multiple post labeling delays (PLD) to replace PET and DSC for CVR and transit time mapping in 26 Moyamoya patients. Images were collected using simultaneous PET/MRI with acetazolamide. CVR, CBF, arterial transit time (ATT), and time-to-maximum (Tmax) were measured in different flow territories. Results showed that CVR was lower in occluded regions than normal regions (by 68 ± 12%, 52 ± 5%, and 56 ± 9%, for PET, single- and multi-PLD PCASL, respectively, all p < 0.05). Multi-PLD PCASL correlated slightly higher with PET (CCC = 0.36 and 0.32 in affected and unaffected territories respectively). Vasodilation caused ATT to reduce by 4.5 ± 3.1% (p < 0.01) in occluded regions. ATT correlated significantly with Tmax (R2 > 0.35, p < 0.01). Therefore, multi-PLD ASL is recommended for CVR studies due to its high agreement with the reference PET technique and the capability of measuring transit time.


Assuntos
Doença de Moyamoya , Circulação Cerebrovascular/fisiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Doença de Moyamoya/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Marcadores de Spin
13.
Curr Alzheimer Res ; 19(10): 716-723, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35927922

RESUMO

BACKGROUND: Poststroke cognitive impairment (PSCI) is a prevalent cause of disability in people with stroke. PSCI results from either lesion-dependent loss of cognitive function or augmentation of Alzheimer's pathology due to vascular insufficiency. The lack of prestroke cognitive assessments limits the clear understanding of the impact of PSCI on cognition. OBJECTIVE: The present study aims to make a direct comparison of longitudinal cognitive assessment results to clarify the impact of ischemic stroke on PSCI and assess the cognitive decline in PSCI compared to people with Alzheimer's disease (AD). METHODS: All study participants had their Mini-Mental State Examination (MMSE) at the chronic poststroke stage (≥6 months after stroke), which was compared with prestroke or acute poststroke (<6 months after stroke) MMSE to investigate the two aspects of PSCI. A group of patients with AD was used to reference the speed of neurodegenerative cognitive deterioration. Repeated measures analysis of variance was used to compare the longitudinal change of MMSE. RESULTS: MMSE score between acute and chronic poststroke revealed a 1.8 ± 6.49 decline per year (n=76), which was not significantly different from the AD patients who underwent cholinesterase inhibitors treatment (-1.11 ± 2.61, p=0.35, n=232). MMSE score between prestroke and chronic poststroke (n=33) revealed a significant decline (-6.52 ± 6.86, p < 0.001). In addition, their cognitive deterioration was significantly associated with sex, age, and stroke over the white matter or basal ganglia. CONCLUSION: Ischemic stroke substantially affects cognition with an average six-point drop in MMSE. The rate of cognitive decline in PSCI was similar to AD, and those with white matter or basal ganglia infarct were at greater risk of PSCI.


Assuntos
Isquemia Encefálica , Disfunção Cognitiva , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Seguimentos , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/psicologia , Acidente Vascular Cerebral/complicações
14.
Clin Neurol Neurosurg ; 195: 105959, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32480198

RESUMO

OBJECTIVES: Cholinesterase inhibitors (ChEIs) are the most effective treatment for Alzheimer disease (AD), but the response to treatment varies. Vascular lesions are associated with the pathogenesis of AD, and cerebral microbleeds (CMBs) are an indicator of hemorrhagic vascular pathology, which can be detected through susceptibility-weighted magnetic resonance imaging (SWMRI). This study investigated the association between CMBs and ChEI treatment response in patients with AD. PATIENTS AND METHODS: We reviewed the medical records of 112 Taiwanese people with mild to moderate AD and at least 2 years of ChEI treatment between 2009 and 2016. Their baseline CMBs were quantified using the Microbleed Anatomical Rating Scale on SWMRI. Cognitive function of the patients was assessed using the Mini-Mental State Examination (MMSE) and Cognitive Abilities Screening Instrument (CASI). Student t test and multivariable logistic regression were used to analyze the association between cognitive decline and CMBs. RESULTS: The mean age of the study population was 76.0 ±â€¯8.0 years. In total, 79 out of 112 patients were women. The presence of deep, but not lobar CMBs at baseline was associated with a significant cognitive decline according to the MMSE and CASI, particularly in long-term memory, attention, orientation, mental manipulation, and verbal fluency. Among deep CMBs, those in the basal ganglia and thalamus were significantly associated with cognitive decline. CONCLUSIONS: Deep CMBs, particularly those in the basal ganglia and thalamus, but not lobar CMBs, are associated with poor response to ChEI treatment in people with AD. This can serve as a biomarker for predicting ChEI treatment response.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Encéfalo/diagnóstico por imagem , Hemorragia Cerebral/complicações , Inibidores da Colinesterase/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/complicações , Doença de Alzheimer/diagnóstico por imagem , Hemorragia Cerebral/diagnóstico por imagem , Progressão da Doença , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
15.
Sci Rep ; 8(1): 16803, 2018 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-30429535

RESUMO

Sixty-seven patients with first acute ischemic stroke onset between 3 to 7 days and 25 age- and sex- matched controls were analyzed for the performance of a resting-state functional MRI to investigate whether the functional connectivity (FC) of the motor network in acute ischemic stroke is independently associated with functional outcomes. The FC of cortical motor network and default mode network was analyzed. The FC was compared between controls, patients with favorable outcomes (modified Rankin Scale, mRS ≤1), and patients with unfavorable outcomes (mRS ≥2) at 3 months. Of the 67 patients, 23 (34%) exhibited unfavorable outcomes. In multivariate analysis, the FC between ipsilesional primary motor cortex (M1) and contralesional dorsal premotor area (PMd) ≤0.63, were independently associated with unfavorable outcomes (odds ratio = 6.32, P = 0.032), whereas the FC of default mode network was not different between groups. The interhemispheric FC of the motor network is an independent predictor of functional outcomes in patients with acute ischemic stroke.


Assuntos
Isquemia Encefálica/diagnóstico , Córtex Motor/fisiopatologia , Acidente Vascular Cerebral/diagnóstico , Adulto , Idoso , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/fisiopatologia , Mapeamento Encefálico , Estudos de Casos e Controles , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Rede Nervosa/fisiopatologia , Vias Neurais/fisiopatologia , Prognóstico , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/fisiopatologia
16.
Neuroscience ; 379: 142-151, 2018 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-29530810

RESUMO

Neural activity varies continually from moment to moment. Such temporal variability (TV) has been highlighted as a functionally specific brain property playing a fundamental role in cognition. We sought to investigate the mechanisms involved in TV changes between two basic behavioral states, namely having the eyes open (EO) or eyes closed (EC) in vivo in humans. To these ends we acquired BOLD fMRI, ASL, and [18F]-fluoro-deoxyglucose PET in a group of healthy participants (n = 15), along with BOLD fMRI and [18F]-flumazenil PET in a separate group (n = 19). Focusing on an EO- vs EC-sensitive region in the occipital cortex (identified in an independent sample), we show that TV is constrained in the EO condition compared to EC. This reduction is correlated with an increase in energy consumption and with regional GABAA receptor density. This suggests that the modulation of TV by behavioral state involves an increase in overall neural activity that is related to an increased effect from GABAergic inhibition in addition to any excitatory changes. These findings contribute to our understanding of the mechanisms underlying activity variability in the human brain and its control.


Assuntos
Lobo Occipital/diagnóstico por imagem , Lobo Occipital/fisiologia , Receptores de GABA-A/metabolismo , Ácido gama-Aminobutírico/metabolismo , Adulto , Circulação Cerebrovascular/fisiologia , Feminino , Flumazenil , Fluordesoxiglucose F18 , Moduladores GABAérgicos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Oxigênio/sangue , Periodicidade , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Adulto Jovem
17.
Diagn Cytopathol ; 45(3): 257-261, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27888664

RESUMO

Effusion-based lymphoma is a rare and unique type of large B-cell lymphoma presenting in effusion without a mass lesion. It shares many clinicopathological features with primary effusion lymphoma (PEL), but is distinct from PEL by the absence of HHV8 association. Double hit lymphoma (DHL) is an aggressive B-cell lymphoma, defined by concurrent rearrangement of MYC and BCL2 or BCL6. DHL often presents as lymphadenopathy or an extranodal mass, but rarely occurs in effusion. Here we report a 61-year-old male with alcoholic cirrhosis presenting as massive ascites and left pleural effusion. He has no HIV, HBV or HCV infection and no mass lesion by CT scans. Cytology of both pleural effusion and ascites show large lymphoma cells with plasmablastic morphology characterized by pleomorphic and eccentric nuclei, prominent nucleoli and frequent mitoses. Immunohistochemical study with cell block shows that the lymphoma cells express plasma cell-related markers (CD138, MUM-1 and EMA), but not CD3, CD30, CD45, B-cell markers (CD19, CD20, CD79a, and PAX5), HHV8, ALK or cytokeratin. EBER is positive in most lymphoma cells. Fluorescence in situ hybridization reveals rearrangement at the IGH, BCL2, and MYC loci, but not at BCL6. It is diagnosed as an EBV-associated but HHV8-unrelated double hit effusion-based lymphoma with plasmablastic features. The patient passed away soon after diagnosis without chemotherapy. This is the first reported case of double-hit effusion-based lymphoma with MYC and BCL2 rearrangement. This case illustrates the importance of integrating clinical, cytological, immunophenotypical, and molecular findings to reach a correct diagnosis. Diagn. Cytopathol. 2017;45:257-261. © 2016 Wiley Periodicals, Inc.


Assuntos
Infecções por Vírus Epstein-Barr/diagnóstico , Linfoma Plasmablástico/diagnóstico , Derrame Pleural Maligno/diagnóstico , Evolução Fatal , Herpesvirus Humano 8 , Humanos , Masculino , Pessoa de Meia-Idade , Linfoma Plasmablástico/virologia , Derrame Pleural Maligno/virologia
18.
J Neurointerv Surg ; 9(4): 399-404, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27510884

RESUMO

BACKGROUND AND PURPOSE: MR angiography (MRA) is an increasingly used evaluation method following intracranial stenting. However, the various artifacts created by the stent limit this technique. The purpose of this study was to investigate the effects of various concentrations of gadolinium contrast agent on the visibility and signal characteristics of two stents using the a contrast enhanced MRA technique. MATERIAL AND METHOD: Two intracranial stents (Enterprise and Helistent) were placed in polyvinyl chloride tubes as vascular phantoms. They were filled with six different doses of gadolinium contrast agent (1.0, 2.0, 4.0, 6.0, 8.0, and 10.0 mmol/L dimeglumine gadopentetate, respectively) and imaged using 3 T and 1.5 T MR systems. Relative in-stent signal (RIS) was calculated and artificial luminal narrowing (ALN) was obtained using pixel by pixel analysis. RESULT: The Enterprise stent, performed in both 1.5 T and 3 T MR systems, showed mean RIS values much less than those for the Helistent for all different doses of gadolinium solution. Increased gadolinium concentration resulted in a gradual reduction in RIS values in the Enterprise group. Also, ALN in the Enterprise group showed no or little change with various gadolinium doses. CONCLUSIONS: The Enterprise stent demonstrated good luminal visibility regardless of gadolinium concentration. The relative in-stent signals were more predictable in the Enterprise stent with various doses of gadolinium. Therefore, the Enterprise stent has been shown to provide better in-stent visibility compared with the Helistent using various gadolinium doses.


Assuntos
Meios de Contraste , Gadolínio DTPA , Angiografia por Ressonância Magnética/métodos , Stents , Artefatos , Relação Dose-Resposta a Droga , Gadolínio , Humanos , Técnicas In Vitro , Imagens de Fantasmas
19.
Interv Neuroradiol ; 22(2): 187-95, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26542728

RESUMO

BACKGROUND: Severe intracranial arterial stenosis results in more than 10% incidence of stroke and transient ischemic attack. Using undersized angioplasty with off-label closed-cell Enterprise stent may be a feasible alternative option for treating patients with intracranial atherosclerotic disease who fail dual-antiplatelet medical therapy. The results of the authors' study are presented in this paper. MATERIALS AND METHODS: Between January 2013 and July 2014, 24 symptomatic patients with a total of 30 intracranial arterial stenotic lesions refractory to medical therapy, who underwent undersized angioplasty and Enterprise stenting, were retrospectively reviewed in the authors' institution. The results evaluated include technical success rate, clinical outcome measured as modified Rankin Scale at presentation and follow-up, peri-procedural morbidity within 30 days and 1 year, and follow-up vessel patency. RESULTS: Stent deployment was successfully achieved in all stenotic lesions (30/30). Mean pre-stent and post-stent diameter residual stenosis was 81% and 18%, respectively. The peri-procedural complication rate during 30 days after stenting was 10% per lesion (3/30), including intracranial hemorrhage, in-stent thrombosis and ischemic stroke. No further thromboembolic event or complication occurred in any patient more than 30 days after stenting. Modified Rankin scale ≤ 2 was observed in 64% and 83% of patients at initial presentation and follow-up (mean 15.8 months), respectively. Imaging follow-up was available in 17 of 24 patients (70.8%) and 20 of 30 treated lesions (66.6%) with a mean follow-up period of 15.4 months. Only one asymptomatic in-stent restenosis occurred in 20 available lesions (5.0%). CONCLUSION: This preliminary study suggests that using undersized angioplasty and Enterprise stenting may effectively treat high-degree symptomatic intracranial arterial stenosis with favorable clinical and angiographic outcome.


Assuntos
Angioplastia/métodos , Doenças Arteriais Cerebrais/terapia , Stents , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Cerebral , Doenças Arteriais Cerebrais/cirurgia , Feminino , Seguimentos , Oclusão de Enxerto Vascular/epidemiologia , Humanos , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Resultado do Tratamento
20.
PLoS One ; 11(1): e0145999, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26731534

RESUMO

INTRODUCTION: Application of computed tomography for monitoring intracranial stents is limited because of stent-related artifacts. Our purpose was to evaluate the effect of gemstone spectral imaging on the intracranial stent and stent lumen. MATERIALS AND METHODS: In vitro, we scanned Enterprise stent phantom and a stent-cheese complex using the gemstone spectral imaging protocol. Follow-up gemstone spectral images of 15 consecutive patients with placement of Enterprise from January 2013 to September 2014 were also retrospectively reviewed. We used 70-keV, 140-keV, iodine (water), iodine (calcium), and iodine (hydroxyapatite) images to evaluate their effect on the intracranial stent and stent lumen. Two regions of interest were individually placed in stent lumen and adjacent brain tissue. Contrast-to-noise ratio was measured to determine image quality. The maximal diameter of stent markers was also measured to evaluate stent-related artifact. Two radiologists independently graded the visibility of the lumen at the maker location by using a 4-point scale. The mean of grading score, contrast/noise ratio and maximal diameter of stent markers were compared among all modes. All results were analyzed by SPSS version 20. RESULTS: In vitro, iodine (water) images decreased metallic artifact of stent makers to the greatest degree. The most areas of cheese were observed on iodine (water) images. In vivo, iodine (water) images had the smallest average diameter of stent markers (0.33 ± 0.17mm; P < .05) and showed the highest mean grading score (2.94 ± 0.94; P < .05) and contrast/noise ratio of in-stent lumen (160.03 ±37.79; P < .05) among all the modes. CONCLUSION: Iodine (water) images can help reduce stent-related artifacts of Enterprise and enhance contrast of in-stent lumen. Spectral imaging may be considered a noninvasive modality for following-up patients with in-stent stenosis.


Assuntos
Encéfalo/irrigação sanguínea , Angiografia Coronária/métodos , Stents , Tomografia Computadorizada por Raios X/métodos , Idoso , Artefatos , Meios de Contraste/análise , Feminino , Humanos , Iodo/análise , Masculino , Pessoa de Meia-Idade
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