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BACKGROUND: Lifestyle modification interventions for adults with intellectual disabilities have had, to date, mixed effectiveness. This study aimed to understand how lifestyle modification interventions for adults with intellectual disabilities work, for whom they work and in what circumstances. METHODS: A realist evidence synthesis was conducted that incorporated input from adults with intellectual disabilities and expert researchers. Following the development of an initial programme theory based on key literature and input from people with lived experience and academics working in this field, five major databases (MEDLINE, EMBASE, CINAHL, PsycINFO and ASSIA) and clinical trial repositories were systematically searched. Data from 79 studies were synthesised to develop context, mechanism and outcome configurations (CMOCs). RESULTS: The contexts and mechanisms identified related to the ability of adults with intellectual disabilities to actively take part in the intervention, which in turn contributes to what works, for whom and in what circumstances. The included CMOCs related to support involvement, negotiating the balance between autonomy and behaviour change, fostering social connectedness and fun, accessibility and suitability of intervention strategies and delivery and broader behavioural pathways to lifestyle change. It is also essential to work with people with lived experiences when developing and evaluating interventions. CONCLUSIONS: Future lifestyle interventions research should be participatory in nature, and accessible data collection methods should also be explored as a way of including people with severe and profound intellectual disabilities in research. More emphasis should be given to the broader benefits of lifestyle change, such as opportunities for social interaction and connectedness.
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Deficiência Intelectual , Humanos , Deficiência Intelectual/reabilitação , Adulto , Participação do PacienteRESUMO
BACKGROUND: Adults with intellectual disabilities (IDs) are susceptible to multiple health risk behaviours such as alcohol consumption, smoking, low physical activity, sedentary behaviour and poor diet. Lifestyle modification interventions can prevent or reduce negative health consequences caused by these behaviours. We aim to determine the effectiveness of lifestyle modification interventions and their components in targeting health risk behaviours in adults with IDs. METHODS: A systematic review and meta-analysis were conducted. Electronic databases, clinical trial registries, grey literature and citations of systematic reviews and included studies were searched in January 2021 (updated February 2022). Randomised controlled trials and non-randomised controlled trials targeting alcohol consumption, smoking, low physical activity, sedentary behaviours and poor diet in adults (aged ≥ 18 years) with ID were included. Meta-analysis was conducted at the intervention level (pairwise and network meta-analysis) and the component-level (component network meta-analysis). Studies were coded using Michie's 19-item theory coding scheme and 94-item behaviour change taxonomies. Risk of bias was assessed using the Cochrane Risk of Bias (ROB) Version 2 and Risk of Bias in Non-randomised Studies of Interventions (ROBINS-I). The study involved a patient and public involvement (PPI) group, including people with lived experience, who contributed extensively by shaping the methodology, providing valuable insights in interpreting results and organising of dissemination events. RESULTS: Our literature search identified 12 180 articles, of which 80 studies with 4805 participants were included in the review. The complexity of lifestyle modification intervention was dismantled by identifying six core components that influenced outcomes. Interventions targeting single or multiple health risk behaviours could have a single or combination of multiple core-components. Interventions (2 RCTS; 4 non-RCTs; 228 participants) targeting alcohol consumption and smoking behaviour were effective but based on limited evidence. Similarly, interventions targeting low physical activity only (16 RCTs; 17 non-RCTs; 1413 participants) or multiple behaviours (low physical activity only, sedentary behaviours and poor diet) (17 RCTs; 24 non-RCTs; 3164 participants) yielded mixed effectiveness in outcomes. Most interventions targeting low physical activity only or multiple behaviours generated positive effects on various outcomes while some interventions led to no change or worsened outcomes, which could be attributed to the presence of a single core-component or a combination of similar core components in interventions. The intervention-level meta-analysis for weight management outcomes showed that none of the interventions were associated with a statistically significant change in outcomes when compared with treatment-as-usual and each other. Interventions with core-components combination of energy deficit diet, aerobic exercise and behaviour change techniques showed the highest weight loss [mean difference (MD) = -3.61, 95% credible interval (CrI) -9.68 to 1.95] and those with core-components combination dietary advice and aerobic exercise showed a weight gain (MD 0.94, 95% CrI -3.93 to 4.91). Similar findings were found with the component network meta-analysis for which additional components were identified. Most studies had a high and moderate risk of bias. Various theories and behaviour change techniques were used in intervention development and adaptation. CONCLUSION: Our systematic review is the first to comprehensively explore lifestyle modification interventions targeting a range of single and multiple health risk behaviours in adults with ID, co-produced with people with lived experience. It has practical implications for future research as it highlights the importance of mixed-methods research in understanding lifestyle modification interventions and the need for population-specific improvements in the field (e.g., tailored interventions, development of evaluation instruments or tools, use of rigorous research methodologies and comprehensive reporting frameworks). Wide dissemination of related knowledge and the involvement of PPI groups, including people with lived experience, will help future researchers design interventions that consider the unique needs, desires and abilities of people with ID.
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Deficiência Intelectual , Humanos , Deficiência Intelectual/reabilitação , Adulto , Comportamentos de Risco à Saúde , Exercício Físico , Consumo de Bebidas Alcoólicas/terapia , Consumo de Bebidas Alcoólicas/prevenção & controleRESUMO
In this review, concepts of algorithmic bias and fairness are defined qualitatively and mathematically. Illustrative examples are given of what can go wrong when unintended bias or unfairness in algorithmic development occurs. The importance of explainability, accountability, and transparency with respect to artificial intelligence algorithm development and clinical deployment is discussed. These are grounded in the concept of "primum no nocere" (first, do no harm). Steps to mitigate unfairness and bias in task definition, data collection, model definition, training, testing, deployment, and feedback are provided. Discussions on the implementation of fairness criteria that maximize benefit and minimize unfairness and harm to neuroradiology patients will be provided, including suggestions for neuroradiologists to consider as artificial intelligence algorithms gain acceptance into neuroradiology practice and become incorporated into routine clinical workflow.
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Algoritmos , Inteligência Artificial , Humanos , Radiologistas , Fluxo de TrabalhoRESUMO
A minimized and efficient low temperature loading device cooling with Peltier coolers for indentation test is developed. Both specimen and indentation tip are immersed in 50% methanol-water solution, totally eliminating the contact thermal drift problem. Low temperature indentation tests down to 253.8 K can be realized within 10 min. The size of the device is miniaturized within 50 × 40 × 30 mm3, and no vacuum environment is required. Monocrystalline copper is tested to perform the feasibility of the device. Based on the simple structure and stable experimental effect, the developed device can be integrated into various types of current indentation devices to attach low temperature testing ability.
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OBJECTIVE: To examine potential genetic relationships between migraine and the two distinct phenotypes posterior circulation ischemic stroke (PCiS) and anterior circulation ischemic stroke (ACiS), we generated migraine polygenic risk scores (PRSs) and compared these between PCiS and ACiS, and separately vs. non-stroke control subjects. METHODS: Acute ischemic stroke cases were classified as PCiS or ACiS based on lesion location on diffusion-weighted MRI. Exclusion criteria were lesions in both vascular territories or uncertain territory; supratentorial PCiS with ipsilateral fetal posterior cerebral artery; and cases with atrial fibrillation. We generated migraine PRS for three migraine phenotypes (any migraine; migraine without aura; migraine with aura) using publicly available GWAS data and compared mean PRSs separately for PCiS and ACiS vs. non-stroke control subjects, and between each stroke phenotype. RESULTS: Our primary analyses included 464 PCiS and 1079 ACiS patients with genetic European ancestry. Compared to non-stroke control subjects (n=15396), PRSs of any migraine were associated with increased risk of PCiS (p=0.01-0.03) and decreased risk of ACiS (p=0.010-0.039). Migraine without aura PRSs were significantly associated with PCiS (p=0.008-0.028), but not with ACiS. When comparing PCiS vs. ACiS directly, migraine PRSs were higher in PCiS vs. ACiS for any migraine (p=0.001-0.010) and migraine without aura (p=0.032-0.048). Migraine with aura PRS did not show a differential association in our analyses. CONCLUSIONS: Our results suggest a stronger genetic overlap between unspecified migraine and migraine without aura with PCiS compared to ACiS. Possible shared mechanisms include dysregulation of cerebral vessel endothelial function.
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AVC Isquêmico , Enxaqueca com Aura , Enxaqueca sem Aura , Imagem de Difusão por Ressonância Magnética , Humanos , Enxaqueca com Aura/diagnóstico por imagem , Enxaqueca com Aura/genética , Enxaqueca sem Aura/diagnóstico por imagem , Enxaqueca sem Aura/genética , Fatores de RiscoRESUMO
OBJECTIVES: To assess the cost-effectiveness of uterine artery embolisation (UAE) and myomectomy for women with symptomatic uterine fibroids wishing to avoid hysterectomy. DESIGN: Economic evaluation alongside the FEMME randomised controlled trial. SETTING: 29 UK hospitals. POPULATION: Premenopausal women who had symptomatic uterine fibroids amenable to UAE or myomectomy wishing to avoid hysterectomy. 254 women were randomised to UAE (127) and myomectomy (127). METHODS: A within-trial cost-utility analysis was conducted from the perspective of the UK NHS. MAIN OUTCOME MEASURES: Quality-adjusted life years (QALYs) measured using the EuroQoL EQ-5D-3L, combined with costs to estimate cost-effectiveness over 2 and 4 years of follow-up. RESULTS: Over a 2-year time horizon, UAE was associated with higher mean costs (difference £645; 95% CI -1381 to 2580) and lower QALYs (difference -0.09; 95% CI -0.11 to -0.04) when compared with myomectomy. Similar results were observed over the 4-year time horizon. Thus, UAE was dominated by myomectomy. Results of the sensitivity analyses were consistent with the base case results for both years. Over 2 years, UAE was associated with higher costs (difference £456; 95% CI -1823 to 3164) and lower QALYs (difference -0.06; 95% CI -0.11 to -0.02). CONCLUSIONS: Myomectomy is a cost-effective option for the treatment of uterine fibroids. The differences in costs and QALYs are small. Women should be fully informed and have the option to choose between the two procedures. TWEETABLE ABSTRACT: Fully informed women with uterine fibroids should have a choice between uterine artery embolisation or myomectomy.
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Leiomioma/cirurgia , Embolização da Artéria Uterina/economia , Miomectomia Uterina/economia , Neoplasias Uterinas/cirurgia , Adulto , Análise Custo-Benefício , Feminino , Humanos , Leiomioma/economia , Pessoa de Meia-Idade , Pré-Menopausa , Anos de Vida Ajustados por Qualidade de Vida , Resultado do Tratamento , Neoplasias Uterinas/economiaRESUMO
BACKGROUND: Bariatric surgery can be effective in weight reduction and diabetes remission in some patients, but is expensive. The costs of bariatric surgery in patients with obesity and type 2 diabetes mellitus (T2DM) were explored here. METHODS: Population-based retrospectively gathered data on patients with obesity and T2DM from the Hong Kong Hospital Authority (2006-2017) were evaluated. Direct medical costs from baseline up to 60 months were calculated based on the frequency of healthcare service utilization and dispensing of diabetes medication. Charlson Co-morbidity Index (CCI) scores and co-morbidity rates were measured to compare changes in co-morbidities between surgically treated and control groups over 5 years. One-to-five propensity score matching was applied. RESULTS: Overall, 401 eligible surgical patients were matched with 1894 non-surgical patients. Direct medical costs were much higher for surgical than non-surgical patients in the index year (36 752 and 5788 respectively; P < 0·001) mainly owing to the bariatric procedure. The 5-year cumulative costs incurred by surgical patients were also higher (54 135 versus 28 603; P < 0·001). Although patients who had bariatric surgery had more visits to outpatient and allied health professionals than those who did not across the 5-year period, surgical patients had shorter length of stay in hospitals than non-surgical patients in year 2-5. Surgical patients had significantly better CCI scores than controls after the baseline measurement (mean 3·82 versus 4·38 at 5 years; P = 0·016). Costs of glucose-lowering medications were similar between two groups, except that surgical patients had significantly lower costs of glucose-lowering medications in year 2 (973 versus 1395; P = 0.012). CONCLUSION: Bariatric surgery in obese patients with T2DM is expensive, but leads to an improved co-morbidity profile, and reduced length of hospitalization.
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Cirurgia Bariátrica/economia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Obesidade/economia , Assistência Ambulatorial/economia , Assistência Ambulatorial/estatística & dados numéricos , Estudos de Casos e Controles , Comorbidade , Diabetes Mellitus Tipo 2/economia , Serviço Hospitalar de Emergência/economia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Hong Kong/epidemiologia , Humanos , Hipoglicemiantes/economia , Hipoglicemiantes/uso terapêutico , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Obesidade/cirurgia , Visita a Consultório Médico/economia , Visita a Consultório Médico/estatística & dados numéricos , Estudos RetrospectivosRESUMO
AIM: To compare costs for three groups of people with type 2 diabetes, those at high risk of future cardiovascular disease, those without cardiovascular disease and those with established cardiovascular disease, and to also compare costs incurred by people with type 2 diabetes with an incident cardiovascular disease event with those who remain incident event-free over a 3-year period. METHODS: Data about people with type 2 diabetes in Scotland were obtained from the Scottish Care Information Diabetes registry. Data linkage was used to retrieve information on healthcare utilization, care home use and deaths. Productivity effects were estimated for those of non-pensionable age. We estimated costs over 12 months (prevalent cardiovascular disease) and 3 years from incident cardiovascular disease event. RESULTS: Mean annual cost per person with established cardiovascular disease was £6900, £3300 for a person at high risk of future cardiovascular disease, and £2500 for a person without cardiovascular disease and not at high risk. In year 1, the cost of an incident cardiovascular disease event was £16 700 compared with £2100 for people without an incident event. Over 2 years, the cumulative costs were £21 500 and £4200, and by year 3, £25 000 and £5900, respectively. CONCLUSIONS: Cardiovascular disease in people with type 2 diabetes places a significant financial burden on healthcare and the wider economy. Our results emphasize the financial consequences of cardiovascular disease prevention strategies.
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Doenças Cardiovasculares/economia , Diabetes Mellitus Tipo 2/epidemiologia , Custos de Cuidados de Saúde , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prevalência , Escócia/epidemiologiaRESUMO
OBJECTIVE: Posterior circulation ischemic stroke (PCiS) constitutes 20-30% of ischemic stroke cases. Detailed information about differences between PCiS and anterior circulation ischemic stroke (ACiS) remains scarce. Such information might guide clinical decision making and prevention strategies. We studied risk factors and ischemic stroke subtypes in PCiS vs. ACiS and lesion location on magnetic resonance imaging (MRI) in PCiS. METHODS: Out of 3,301 MRIs from 12 sites in the National Institute of Neurological Disorders and Stroke (NINDS) Stroke Genetics Network (SiGN), we included 2,381 cases with acute DWI lesions. The definition of ACiS or PCiS was based on lesion location. We compared the groups using Chi-squared and logistic regression. RESULTS: PCiS occurred in 718 (30%) patients and ACiS in 1663 (70%). Diabetes and male sex were more common in PCiS vs. ACiS (diabetes 27% vs. 23%, p < 0.05; male sex 68% vs. 58%, p < 0.001). Both were independently associated with PCiS (diabetes, OR = 1.29; 95% CI 1.04-1.61; male sex, OR = 1.46; 95% CI 1.21-1.78). ACiS more commonly had large artery atherosclerosis (25% vs. 20%, p < 0.01) and cardioembolic mechanisms (17% vs. 11%, p < 0.001) compared to PCiS. Small artery occlusion was more common in PCiS vs. ACiS (20% vs. 14%, p < 0.001). Small artery occlusion accounted for 47% of solitary brainstem infarctions. CONCLUSION: Ischemic stroke subtypes differ between the two phenotypes. Diabetes and male sex have a stronger association with PCiS than ACiS. Definitive MRI-based PCiS diagnosis aids etiological investigation and contributes additional insights into specific risk factors and mechanisms of injury in PCiS.
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Doenças Arteriais Cerebrais/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Insuficiência Vertebrobasilar/complicações , Idoso , Arteriopatias Oclusivas/complicações , Artéria Basilar/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem , Fenótipo , Acidente Vascular Cerebral/patologia , Artéria Vertebral/patologiaRESUMO
BACKGROUND AND PURPOSE: Accurate automated infarct segmentation is needed for acute ischemic stroke studies relying on infarct volumes as an imaging phenotype or biomarker that require large numbers of subjects. This study investigated whether an ensemble of convolutional neural networks trained on multiparametric DWI maps outperforms single networks trained on solo DWI parametric maps. MATERIALS AND METHODS: Convolutional neural networks were trained on combinations of DWI, ADC, and low b-value-weighted images from 116 subjects. The performances of the networks (measured by the Dice score, sensitivity, and precision) were compared with one another and with ensembles of 5 networks. To assess the generalizability of the approach, we applied the best-performing model to an independent Evaluation Cohort of 151 subjects. Agreement between manual and automated segmentations for identifying patients with large lesion volumes was calculated across multiple thresholds (21, 31, 51, and 70 cm3). RESULTS: An ensemble of convolutional neural networks trained on DWI, ADC, and low b-value-weighted images produced the most accurate acute infarct segmentation over individual networks (P < .001). Automated volumes correlated with manually measured volumes (Spearman ρ = 0.91, P < .001) for the independent cohort. For the task of identifying patients with large lesion volumes, agreement between manual outlines and automated outlines was high (Cohen κ, 0.86-0.90; P < .001). CONCLUSIONS: Acute infarcts are more accurately segmented using ensembles of convolutional neural networks trained with multiparametric maps than by using a single model trained with a solo map. Automated lesion segmentation has high agreement with manual techniques for identifying patients with large lesion volumes.
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Isquemia Encefálica/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Neuroimagem/métodos , Idoso , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/diagnóstico por imagemRESUMO
Walking is the primary form of physical activity performed by people with Multiple Sclerosis (MS), therefore it is important to ensure the validity of tools employed to measure walking activity. The aim of this study was to assess the criterion validity of the activPAL3 activity monitor during overground walking in people with MS. Validity of the activPAL3 accelerometer was compared to video observation in 20 people moderately affected by MS. Participants walked 20-30m twice along a straight quiet corridor at a comfortable speed. Inter-rater reliability of video observations was excellent (all intraclass correlations >0.99). The mean difference (activPAL3- mean of raters) was -4.70±9.09, -4.55s±10.76 and 1.11s±1.11 for steps taken, walking duration and upright duration respectively. These differences represented 8.7%, 10.0% and 1.8% of the mean for each measure respectively. The activPAL3 tended to underestimate steps taken and walking duration in those who walked at cadences of ≤38 steps/min by 60% and 47%, respectively. The activPAL3 is valid for measuring walking activity in people moderately affected by MS. It is accurate for upright duration regardless of cadence. In participants with slow walking cadences, outcomes of steps taken and walking duration should be interpreted with caution.
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Exercício Físico , Monitorização Fisiológica/métodos , Esclerose Múltipla/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , CaminhadaRESUMO
BACKGROUND: The ability to predict outcomes in acutely comatose cardiac arrest survivors is limited. Brain diffusion-weighted magnetic resonance imaging (DWI MRI) has been shown in initial studies to be a simple and effective prognostic tool. This study aimed to determine the predictive value of previously defined DWI MRI thresholds in a multi-center cohort. METHODS: DWI MRIs of comatose post-cardiac arrest patients were analyzed in this multi-center retrospective observational study. Poor outcome was defined as failure to regain consciousness within 14 days and/or death during the hospitalization. The apparent diffusion coefficient (ADC) value of each brain voxel was determined. ADC thresholds and brain volumes below each threshold were analyzed for their correlation with outcome. RESULTS: 125 patients were included in the analysis. 33 patients (26%) had a good outcome. An ADC value of less than 650 × 10(-6) mm(2)/s in ≥10% of brain volume was highly specific [91% (95% CI 75-98)] and had a good sensitivity [72% (95% CI 61-80)] for predicting poor outcome. This threshold remained an independent predictor of poor outcome in multivariable analysis (p = 0.002). An ADC value of less than 650 × 10(-6) mm(2)/s in >22% of brain volume was needed to achieve 100% specificity for poor outcome. CONCLUSIONS: In patients who remain comatose after cardiac arrest, quantitative DWI MRI findings correlate with early recovery of consciousness. A DWI MRI threshold of 650 × 10(-6) mm(2)/s in ≥10% of brain volume can differentiate patients with good versus poor outcome, though in this patient population the threshold was not 100% specific for poor outcome.
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Encéfalo/patologia , Coma/diagnóstico , Imagem de Difusão por Ressonância Magnética/métodos , Parada Cardíaca/complicações , Avaliação de Resultados em Cuidados de Saúde , Adulto , Idoso , Morte Encefálica , Coma/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
Over the past decade, networks have become a leading model to illustrate both the anatomical relationships (structural networks) and the coupling of dynamic physiology (functional networks) linking separate brain regions. The relationship between these two levels of description remains incompletely understood and an area of intense research interest. In particular, it is unclear how cortical currents relate to underlying brain structural architecture. In addition, although theory suggests that brain communication is highly frequency dependent, how structural connections influence overlying functional connectivity in different frequency bands has not been previously explored. Here we relate functional networks inferred from statistical associations between source imaging of EEG activity and underlying cortico-cortical structural brain connectivity determined by probabilistic white matter tractography. We evaluate spontaneous fluctuating cortical brain activity over a long time scale (minutes) and relate inferred functional networks to underlying structural connectivity for broadband signals, as well as in seven distinct frequency bands. We find that cortical networks derived from source EEG estimates partially reflect both direct and indirect underlying white matter connectivity in all frequency bands evaluated. In addition, we find that when structural support is absent, functional connectivity is significantly reduced for high frequency bands compared to low frequency bands. The association between cortical currents and underlying white matter connectivity highlights the obligatory interdependence of functional and structural networks in the human brain. The increased dependence on structural support for the coupling of higher frequency brain rhythms provides new evidence for how underlying anatomy directly shapes emergent brain dynamics at fast time scales.
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Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Vias Neurais/anatomia & histologia , Vias Neurais/fisiologia , Substância Branca/anatomia & histologia , Substância Branca/fisiologia , Adolescente , Criança , Imagem de Tensor de Difusão , Eletroencefalografia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Modelos Neurológicos , Adulto JovemRESUMO
BACKGROUND AND PURPOSE: The durations of acute ischemic stroke patients' CT or MR perfusion scans may be too short to fully sample the passage of the injected contrast agent through the brain. We tested the potential magnitude of hidden errors related to the truncation of data by short perfusion scans. MATERIALS AND METHODS: Fifty-seven patients with acute ischemic stroke underwent perfusion MR imaging within 12 hours of symptom onset, using a relatively long scan duration (110 seconds). Shorter scan durations (39.5-108.5 seconds) were simulated by progressively deleting the last-acquired images. CBV, CBF, MTT, and time to response function maximum (Tmax) were measured within DWI-identified acute infarcts, with commonly used postprocessing algorithms. All measurements except Tmax were normalized by dividing by the contralateral hemisphere values. The effects of the scan duration on these hemodynamic measurements and on the volumes of lesions with Tmax of >6 seconds were tested using regression. RESULTS: Decreasing scan duration from 110 seconds to 40 seconds falsely reduced perfusion estimates by 47.6%-64.2% of normal for CBV, 1.96%-4.10% for CBF, 133%-205% for MTT, and 6.2-8.0 seconds for Tmax, depending on the postprocessing method. This truncation falsely reduced estimated Tmax lesion volume by 71.5 or 93.8 mL, depending on the deconvolution method. "Lesion reversal" (ie, change from above-normal to apparently normal, or from >6 seconds to ≤6 seconds for the time to response function maximum) with increasing truncation occurred in 37%-46% of lesions for CBV, 2%-4% for CBF, 28%-54% for MTT, and 42%-44% for Tmax, depending on the postprocessing method. CONCLUSIONS: Hidden truncation-related errors in perfusion images may be large enough to alter patient management or affect outcomes of clinical trials.
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Isquemia Encefálica/diagnóstico , Erros de Diagnóstico , Imagem de Perfusão/métodos , Acidente Vascular Cerebral/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Artefatos , Encéfalo/irrigação sanguínea , Circulação Cerebrovascular/fisiologia , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Hemodinâmica , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Fatores de TempoRESUMO
BACKGROUND AND PURPOSE: Selecting acute ischemic stroke patients for reperfusion therapy on the basis of a diffusion-perfusion mismatch has not been uniformly proved to predict a beneficial treatment response. In a prior study, we have shown that combining clinical with MR imaging thresholds can predict clinical outcome with high positive predictive value. In this study, we sought to validate this predictive model in a larger patient cohort and evaluate the effects of reperfusion therapy and stroke side. MATERIALS AND METHODS: One hundred twenty-three consecutive patients with anterior circulation acute ischemic stroke underwent MR imaging within 6 hours of stroke onset. DWI and PWI volumes were measured. Lesion volume and NIHSS score thresholds were used in models predicting good 3-month clinical outcome (mRS 0-2). Patients were stratified by treatment and stroke side. RESULTS: Receiver operating characteristic analysis demonstrated 95.6% and 100% specificity for DWI > 70 mL and NIHSS score > 20 to predict poor outcome, and 92.7% and 91.3% specificity for PWI (mean transit time) < 50 mL and NIHSS score < 8 to predict good outcome. Combining clinical and imaging thresholds led to an 88.8% (71/80) positive predictive value with a 65.0% (80/123) prognostic yield. One hundred percent specific thresholds for DWI (103 versus 31 mL) and NIHSS score (20 versus 17) to predict poor outcome were significantly higher in treated (intravenous and/or intra-arterial) versus untreated patients. Prognostic yield was lower in right- versus left-sided strokes for all thresholds (10.4%-20.7% versus 16.9%-40.0%). Patients with right-sided strokes had higher 100% specific DWI (103.1 versus 74.8 mL) thresholds for poor outcome, and the positive predictive value was lower. CONCLUSIONS: Our predictive model is validated in a much larger patient cohort. Outcome may be predicted in up to two-thirds of patients, and thresholds are affected by stroke side and reperfusion therapy.
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Isquemia Encefálica/patologia , Imagem de Difusão por Ressonância Magnética , Reperfusão , Acidente Vascular Cerebral/patologia , Idoso , Encéfalo/patologia , Isquemia Encefálica/terapia , Infarto Cerebral , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , National Institutes of Health (U.S.) , Seleção de Pacientes , Prognóstico , Curva ROC , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Acidente Vascular Cerebral/terapia , Estados UnidosRESUMO
PURPOSE: This systematic review and meta-analysis aimed to evaluate the risks of complications (infectious and non-infectious) including the need for device removal associated with centrally inserted external catheters compared with totally implantable ports in patients undergoing chemotherapy. METHODS: Relevant major electronic databases were searched from inception to December 2012. All randomized controlled trials (RCT) and observational studies that compared centrally inserted external catheters with totally implantable ports in patients undergoing chemotherapy were included in the systematic review. Meta-analysis was carried out to estimate the odds ratios of device-associated complications, including infection, non-infectious complications and device removal associated with external catheters relative to implantable ports. RESULTS: Overall, five RCTs and 25 observational studies were included in the study. The studies were heterogeneous, and included adults and children, with different types of cancer, undergoing chemotherapy. Based on the pooled estimates from included studies, external catheters were associated with approximately a three to four-fold increase in the risks of infections, non-infectious complications and device removal compared implantable ports. CONCLUSION: The findings of this study showed that totally implantable ports are superior to external catheters in terms of catheter-associated complications. However, a formal health technology assessment on the clinical and cost-effectiveness of the use of implantable ports compared with external catheters is needed to inform policy makers of the relative value of investing in totally implantable devices compared with external catheters.
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Antineoplásicos/administração & dosagem , Cateterismo Venoso Central/efeitos adversos , Cateteres de Demora/efeitos adversos , Neoplasias/tratamento farmacológico , Cateterismo Venoso Central/instrumentação , Remoção de Dispositivo , HumanosRESUMO
PURPOSE: To assess the sensitivity and false positive rate (FPR) of neurological examination and somatosensory evoked potentials (SSEPs) to predict poor outcome in adult patients treated with therapeutic hypothermia after cardiopulmonary resuscitation (CPR). METHODS: MEDLINE and EMBASE were searched for cohort studies describing the association of clinical neurological examination or SSEPs after return of spontaneous circulation with neurological outcome. Poor outcome was defined as severe disability, vegetative state and death. Sensitivity and FPR were determined. RESULTS: A total of 1,153 patients from ten studies were included. The FPR of a bilaterally absent cortical N20 response of the SSEP could be calculated from nine studies including 492 patients. The SSEP had an FPR of 0.007 (confidence interval, CI, 0.001-0.047) to predict poor outcome. The Glasgow coma score (GCS) motor response was assessed in 811 patients from nine studies. A GCS motor score of 1-2 at 72 h had a high FPR of 0.21 (CI 0.08-0.43). Corneal reflex and pupillary reactivity at 72 h after the arrest were available in 429 and 566 patients, respectively. Bilaterally absent corneal reflexes had an FPR of 0.02 (CI 0.002-0.13). Bilaterally absent pupillary reflexes had an FPR of 0.004 (CI 0.001-0.03). CONCLUSIONS: At 72 h after the arrest the motor response to painful stimuli and the corneal reflexes are not a reliable tool for the early prediction of poor outcome in patients treated with hypothermia. The reliability of the pupillary response to light and the SSEP is comparable to that in patients not treated with hypothermia.