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71.
Rajpaul Attariwala MD PhD FRCPC FANM Wayne Picker M. Hlth. Sc. 《Journal of magnetic resonance imaging : JMRI》2013,38(2):253-268
Diffusion‐weighted imaging (DWI) is an established functional imaging technique that interrogates the delicate balance of water movement at the cellular level. Technological advances enable this technique to be applied to whole‐body MRI. Theory, b‐value selection, common artifacts and target to background for optimized viewing will be reviewed for applications in the neck, chest, abdomen, and pelvis. Whole‐body imaging with DWI allows novel applications of MRI to aid in evaluation of conditions such as multiple myeloma, lymphoma, and skeletal metastases, while the quantitative nature of this technique permits evaluation of response to therapy. Persisting signal at high b‐values from restricted hypercellular tissue and viscous fluid also permits applications of DWI beyond oncologic imaging. DWI, when used in conjunction with routine imaging, can assist in detecting hemorrhagic degradation products, infection/abscess, and inflammation in colitis, while aiding with discrimination of free fluid and empyema, while limiting the need for intravenous contrast. DWI in conjunction with routine anatomic images provides a platform to improve lesion detection and characterization with findings rivaling other combined anatomic and functional imaging techniques, with the added benefit of no ionizing radiation. J. Magn. Reson. Imaging 2013;38:253–268. © 2013 Wiley Periodicals, Inc. 相似文献
72.
Myles T. Taffel Lyndon Luk Justin M. Ream Andrew B. Rosenkrantz 《Journal l'Association canadienne des radiologistes》2019,70(4):416-423
PurposeTo evaluate whole-lesion 3D-histogram apparent diffusion coefficient (ADC) metrics for assessment of pancreatic malignancy.MethodsForty-two pancreatic malignancies (36 pancreatic adenocarcinoma [PDAC], 6 pancreatic neuroendocrine [PanNET]) underwent abdominal magnetic resonance imaging (MRI) with diffusion-weighted imaging before endoscopic ultrasound biopsy or surgical resection. Two radiologists independently placed 3D volumes of interest to derive whole-lesion histogram ADC metrics. Mann-Whitney tests and receiver operating characteristic analyses were used to assess metrics’ diagnostic performance for lesion histology, T-stage, N-stage, and grade.ResultsWhole-lesion ADC histogram metrics lower in PDACs than PanNETs for both readers (P ≤ .026) were mean ADC (area under the curve [AUC] = 0.787-0.792), mean of the bottom 10th percentile (mean0-10) (AUC = 0.787-0.880), mean of the 10th-25th percentile (mean10-25) (AUC = 0.884-0.917) and mean of the 25th-50th percentile (mean25-50) (AUC = 0.829-0.829). For mean10-25 (metric with highest AUC for identifying PDAC), for reader 1 a threshold > 0.94 × 10?3 mm2/s achieved sensitivity 94% and specificity 83%, and for reader 2 a threshold > 0.82 achieved sensitivity 97% and specificity 67%. Metrics lower in nodal status ≥ N1 than N0 for both readers (P ≤ .043) were mean0-10 (AUC = 0.789-0.822) and mean10-25 (AUC = 0.800-0.822). For mean10-25 (metric with highest AUC for identifying N0), for reader 1 a threshold <1.17 achieved sensitivity 87% and specificity 67%, and for reader 2 a threshold <1.04 achieved sensitivity 87% and specificity 83%. No metric was associated with T-stage (P > .195) or grade (P > .215).ConclusionVolumetric ADC histogram metrics may serve as non-invasive biomarkers of pancreatic malignancy. Mean10-25 outperformed standard mean for lesion histology and nodal status, supporting the role of histogram analysis. 相似文献
73.
Vicent Caballer-Tarazona Natividad Guadalajara-Olmeda David Vivas-Consuelo 《Health policy (Amsterdam, Netherlands)》2019,123(4):427-434
Objectives
This article has two main purposes. Firstly, to model the integrated healthcare expenditure for the entire population of a health district in Spain, according to multimorbidity, using Clinical Risk Groups (CRG). Secondly, to show how the predictive model is applied to the allocation of health budgets.Methods
The database used contains the information of 156,811 inhabitants in a Valencian Community health district in 2013. The variables were: age, sex, CRG’s main health statuses, severity level, and healthcare expenditure. The two-part models were used for predicting healthcare expenditure. From the coefficients of the selected model, the relative weights of each group were calculated to set a case-mix in each health district.Results
Models based on multimorbidity-related variables better explained integrated healthcare expenditure. In the first part of the two-part models, a logit model was used, while the positive costs were modelled with a log-linear OLS regression. An adjusted R2 of 46–49% between actual and predicted values was obtained. With the weights obtained by CRG, the differences found with the case-mix of each health district proved most useful for budgetary purposes.Conclusions
The expenditure models allowed improved budget allocations between health districts by taking into account morbidity, as opposed to budgeting based solely on population size. 相似文献74.
75.
Vanessa Moñivas Palomero Alejandro Durante-Lopez Mario Torres Sanabria Javier Segovia Cubero Jesús González-Mirelis Jorge Vazquez Lopez-Ibor Sara M. Navarro Rico Isabel Krsnik Fernando Dominguez Alejandro Martinez Mingo Francisco J. Hernandez-Perez Gibanel Cavero Susana Mingo Santos 《Journal of the American Society of Echocardiography》2019,32(7):845-853.e1
76.
目的: 通过分析该院药品零加成后慢病门诊费用变化,为后续医保费用管控及合理用药提供参考意见。方法: 使用数据挖掘方法,分别利用费用消耗占比、月度次均费用变化情况以及皮尔逊相关系数(Pearson Correlation Coefficient)分析各类费用变化情况及药品费用对其他费用的影响。结果: 次均总费用、次均西成药费用、次均中草药费用整体呈现下降的趋势,次均检查费用、次均检验费用、次均挂号费用、次均手术费用、次均麻醉费用、次均治疗费用呈现上升趋势。结论: 次均总费用下降主要是由于次均西成药费的下降所产生的,但是次均西成药费下降与次均麻醉费用、次均检验费用、次均检查费用上升是呈现相关性的,这也揭示了次均总费用下降速度慢于次均西成药费下降速度的原因。 相似文献
77.
《Journal of neuroradiology. Journal de neuroradiologie》2020,47(4):272-277
Background and purposeThe ability to predict high-grade meningioma preoperatively is important for clinical surgical planning. The purpose of this study is to evaluate the performance of comprehensive multiparametric MRI, including susceptibility weighted imaging (SWI) and quantitative susceptibility mapping (QSM) in predicting high-grade meningioma both qualitatively and quantitatively.MethodsNinety-two low-grade and 37 higher grade meningiomas in 129 patients were included in this study. Morphological characteristics, quantitative histogram analysis of QSM and ADC images, and tumor size were evaluated to predict high-grade meningioma using univariate and multivariate analyses. Receiver operating characteristic (ROC) analyses were performed on the morphological characteristics. Associations between Ki-67 proliferative index (PI) and quantitative parameters were calculated using Pearson correlation analyses.ResultsFor predicting high-grade meningiomas, the best predictive model in multivariate logistic regression analyses included calcification (β = 0.874, P = 0.110), peritumoral edema (β = 0.554, P = 0.042), tumor border (β = 0.862, P = 0.024), tumor location (β = 0.545, P = 0.039) for morphological characteristics, and tumor size (β = 4 × 10−5, P = 0.004), QSM kurtosis (β = − 5 × 10−3, P = 0.058), QSM entropy (β = − 0.067, P = 0.054), maximum ADC (β = − 1.6 × 10−3, P = 0.003), ADC kurtosis (β = − 0.013, P = 0.014) for quantitative characteristics. ROC analyses on morphological characteristics resulted in an area under the curve (AUC) of 0.71 (0.61–0.81) for a combination of them. There were significant correlations between Ki-67 PI and mean ADC (r = − 0.277, P = 0.031), 25th percentile of ADC (r = − 0.275, P = 0.032), and 50th percentile of ADC (r = − 0.268, P = 0.037).ConclusionsAlthough SWI and QSM did not improve differentiation between low and high-grade meningiomas, combining morphological characteristics and quantitative metrics can help predict high-grade meningioma. 相似文献
78.
《Archives of physical medicine and rehabilitation》2019,100(10):1924-1931
ObjectiveValidation of linking coefficients to transform Pediatric Spinal Cord Injury Activity Measure (PEDI-SCI/AM) scores to adult Spinal Cord Injury-Functional Index (SCI-FI) scores.DesignThis cross-sectional study administered PEDI-SCI/AM and SCI-FI computerized adaptive tests (CATs) and short forms (SFs) to children with SCI and parents or caregivers.SettingHospitals, university, and rehabilitation institute.ParticipantsAbout 107 children with SCI and 96 parent or caregivers.InterventionsNot applicable.Main Outcome MeasuresLinking coefficients estimated SCI-FI (est-SCI-FI) scores from PEDI-SCI/AM scores for matched domains. Correlations between est-SCI-FI and actual SCI-FI scores were calculated. If correlations exceeded the criterion linking (0.866), the following analyses to compare est-SCI-FI and actual SCI-FI scores were conducted: paired t tests, intraclass correlation coefficients (ICCs 3, 1), percent of cases with absolute score differences at different thresholds.ResultsTwo matched domains, PEDI-SCI/AM Daily Routine/SCI-FI Self-Care and PEDI-SCI/AM General Mobility/SCI-FI Basic Mobility, met the linking criterion for both respondent-types (parent and child) and administration modes (CAT and SF). PEDI-SCI/AM Daily Routine and SCI-FI Fine Motor Function did not meet linking criterion for respondent type or mode. The linking criterion was met for wheelchair domains (child SF and CAT) and ambulation domains (child SF only). Significant differences between est-SCI-FI and actual SCI-FI scores were noted for all matched domains except Daily Routine/Self-Care (child SF only; parent SF and CAT). ICC values showed excellent agreement (range=0.75-0.89). Absolute differences between est-SCI-FI and actual SCI-FI scores were less than 1 standard deviation (except wheelchair CAT child).ConclusionsLinking coefficients applied to PEDI-SCI/AM scores can provide valid SCI-FI estimates that vary by domain, mode, and respondent type. 相似文献
79.
《Sleep medicine》2021
ObjectiveThe Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN) might be applicable for assessing delayed sleep-wake phase disorder (DSWPD). We aimed to investigate the reliability and validity of the Japanese version of the BRIAN self-report (J-BRIAN-SR) in DSWPD patients and determine a cutoff score to identify the presence of the disorder.MethodsWe enrolled 60 newly diagnosed DSWPD outpatients and 64 age-matched healthy controls. We used Cronbach's alpha for internal reliability to evaluate J-BRIAN-SR. We confirmed the reliability of the A test and re-test using Pearson's correlation coefficient in the controls. We used confirmatory factor analysis to evaluate the factor structure of J-BRIAN-SR and referenced the Morningness-Eveningness Questionnaire (MEQ) to check concurrent validity. We analyzed the receiver operating characteristic curve (ROC) to determine the J-BRIAN-SR cutoff point for the presence of DSWPD.ResultsThe 18-component scores of the J-BRIAN-SR had an overall reliability coefficient (Cronbach's alpha) of 0.82. We confirmed a high test-retest reliability using an intraclass correlation coefficient (r = 0.84). The correlation between J-BRIAN-SR and MEQ was 0.38 (p = 0.003). The J-BRIAN-SR that we extracted by exploratory factor analysis consisted of three factors. A score of 40 points provided a sensitivity of 80.0% and a specificity of 75.6% for the positivity of DSWPD.ConclusionsThe results of the present study revealed that J-BRIAN-SR is a valid and reliable instrument for screening and evaluating the severity of DSWPD. Our findings will be useful to physicians and patients in Japan and those in clinical settings. 相似文献