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https://www.readbyqxmd.com/read/29146728/source-estimation-of-epileptic-activity-using-eloreta-kurtosis-analysis
#1
Shunichiro Ikeda, Ryouhei Ishii, Leonides Canuet, Roberto D Pascual-Marqui
Exact low-resolution brain electromagnetic tomography (eLORETA) is a technique for three-dimensional representation of the distribution of sources of electrical activity in the brain. Kurtosis analysis allows for identification of spiky activity in the brain. To evaluate the reliability of eLORETA kurtosis analysis, the results of the analysis were compared with those of equivalent current dipole (ECD) and synthetic aperture magnetometry (SAM) kurtosis analysis of magnetoencephalography (MEG) data in a patient with epilepsy with elementary visual seizures in a 6-year follow-up...
November 16, 2017: BMJ Case Reports
https://www.readbyqxmd.com/read/29143940/histogram-analysis-of-diffusion-kurtosis-imaging-derived-maps-may-distinguish-between-low-and-high-grade-gliomas-before-surgery
#2
Xi-Xun Qi, Da-Fa Shi, Si-Xie Ren, Su-Ya Zhang, Long Li, Qing-Chang Li, Li-Ming Guan
OBJECTIVE: To investigate the value of histogram analysis of diffusion kurtosis imaging (DKI) maps in the evaluation of glioma grading. METHODS: A total of 39 glioma patients who underwent preoperative magnetic resonance imaging (MRI) were classified into low-grade (13 cases) and high-grade (26 cases) glioma groups. Parametric DKI maps were derived, and histogram metrics between low- and high-grade gliomas were analysed. The optimum diagnostic thresholds of the parameters, area under the receiver operating characteristic curve (AUC), sensitivity, and specificity were achieved using a receiver operating characteristic (ROC)...
November 16, 2017: European Radiology
https://www.readbyqxmd.com/read/29141363/-characteristics-of-high-resolution-diffusion-weighted-imaging-apparent-diffusion-coefficient-histogram-and-its-correlations-with-cancer-stages-in-patients-with-nasopharyngeal-carcinoma
#3
G J Wang, Y Wang, Y Ye, F Chen, Y T Lu, S L Li
Objective: To investigate the features of apparent diffusion coefficient (ADC) histogram parameters based on entire tumor volume data in high resolution diffusion weighted imaging of nasopharyngeal carcinoma (NPC) and to evaluate its correlations with cancer stages. Methods: This retrospective study included 154 cases of NPC patients[102 males and 52 females, mean age (48±11) years]who had received readout segmentation of long variable echo trains of MRI scan before radiation therapy. The area of tumor was delineated on each section of axial ADC maps to generate ADC histogram by using Image J...
November 7, 2017: Zhonghua Yi Xue za Zhi [Chinese medical journal]
https://www.readbyqxmd.com/read/29140606/mr-textural-analysis-on-t2-flair-images-for-the-prediction-of-true-oligodendroglioma-by-the-2016-who-genetic-classification
#4
Wenting Rui, Yan Ren, Yin Wang, Xinyi Gao, Xiao Xu, Zhenwei Yao
BACKGROUND: The genetic status of 1p/19q is important for differentiating oligodendroglioma, isocitrate-dehydrogenase (IDH)-mutant, and 1p/19q-codeleted from diffuse astrocytoma, IDH-mutant according to the 2016 World Health Organization (WHO) criteria. PURPOSE: To assess the value of magnetic resonance textural analysis (MRTA) on T2 fluid-attenuated inversion recovery (FLAIR) images for making a genetically integrated diagnosis of true oligodendroglioma by WHO guidelines...
November 15, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/29132624/the-value-of-ehr-based-assessment-of-physician-competency-an-investigative-effort-with-internal-medicine-physicians
#5
Kimberly Venta, Erin Baker, Cali Fidopiastis, Kay Stanney
OBJECTIVE: The purpose of this study was to investigate the potential of developing an EHR-based model of physician competency, named the Skill Deficiency Evaluation Toolkit for Eliminating Competency-loss Trends (Skill-DETECT), which presents the opportunity to use EHR-based models to inform selection of Continued Medical Education (CME) opportunities specifically targeted at maintaining proficiency. METHODS: The IBM Explorys platform provided outpatient Electronic Health Records (EHRs) representing 76 physicians with over 5000 patients combined...
December 2017: International Journal of Medical Informatics
https://www.readbyqxmd.com/read/29117481/advanced-diffusion-weighted-imaging-modeling-for-prostate-cancer-characterization-correlation-with-quantitative-histopathologic-tumor-tissue-composition-a-hypothesis-generating-study
#6
Stefanie J Hectors, Sahar Semaan, Christopher Song, Sara Lewis, George K Haines, Ashutosh Tewari, Ardeshir R Rastinehad, Bachir Taouli
Purpose To correlate quantitative diffusion-weighted imaging (DWI) parameters derived from conventional monoexponential DWI, stretched exponential DWI, diffusion kurtosis imaging (DKI), and diffusion-tensor imaging (DTI) with quantitative histopathologic tumor tissue composition in prostate cancer in a preliminary hypothesis-generating study. Materials and Methods This retrospective institutional review board-approved study included 24 patients with prostate cancer (mean age, 63 years) who underwent magnetic resonance (MR) imaging, including high-b-value DWI and DTI at 3...
November 8, 2017: Radiology
https://www.readbyqxmd.com/read/29105178/is-there-evidence-for-more-than-two-diffusion-components-in-abdominal-organs-a-magnetic-resonance-imaging-study-in-healthy-volunteers
#7
Moritz C Wurnig, Manon Germann, Andreas Boss
The most commonly applied model for the description of diffusion-weighted imaging (DWI) data in perfused organs is bicompartmental intravoxel incoherent motion (IVIM) analysis. In this study, we assessed the ground truth of underlying diffusion components in healthy abdominal organs using an extensive DWI protocol and subsequent computation of apparent diffusion coefficient 'spectra', similar to the computation of previously described T2 relaxation spectra. Diffusion datasets of eight healthy subjects were acquired in a 3-T magnetic resonance scanner using 68 different b values during free breathing (equidistantly placed in the range 0-1005 s/mm(2) )...
November 3, 2017: NMR in Biomedicine
https://www.readbyqxmd.com/read/29103978/a-study-on-diffusion-and-kurtosis-features-of-cervical-cancer-based-on-non-gaussian-diffusion-weighted-model
#8
Panying Wang, Deepa Thapa, Guangyao Wu, Qunqi Sun, Hongbing Cai, Fei Tuo
OBJECTIVE: To explore the diffusion and kurtosis features of cervical cancer (CC) and study the feasibility of diffusion kurtosis imaging (DKI) based on the non-Gaussian diffusion-weighted model to differentiate the stage and grade of CC. METHODS: A total of 50 patients with pathologically confirmed CC were enrolled. MRI examinations including DKI (with 5b values 200, 500, 1000, 1500, and 2000smm(-2) were performed before any treatment. The apparent coefficient (Dapp) and the apparent kurtosis value (Kapp) were derived from the non-gaussian diffusion model, and the apparent diffusion coefficient (ADC) was derived from the Gaussian model...
November 2, 2017: Magnetic Resonance Imaging
https://www.readbyqxmd.com/read/29095833/texture-analysis-of-acute-myocardial-infarction-with-ct-first-experience-study
#9
Ricarda Hinzpeter, Matthias W Wagner, Moritz C Wurnig, Burkhardt Seifert, Robert Manka, Hatem Alkadhi
OBJECTIVE: To investigate the feasibility and accuracy of texture analysis to distinguish through objective and quantitative image information between healthy and infarcted myocardium with computed tomography (CT). MATERIALS AND METHODS: Twenty patients (5 females; mean age 56±10years) with proven acute myocardial infarction (MI) and 20 patients (8 females; mean age 42±15years) with no cardiac abnormalities (hereafter termed controls) underwent contrast-enhanced cardiac CT...
2017: PloS One
https://www.readbyqxmd.com/read/29095673/intravoxel-incoherent-motion-and-quantitative-non-gaussian-diffusion-mr-imaging-evaluation-of-the-diagnostic-and-prognostic-value-of-several-markers-of-malignant-and-benign-breast-lesions
#10
Mami Iima, Masako Kataoka, Shotaro Kanao, Natsuko Onishi, Makiko Kawai, Akane Ohashi, Rena Sakaguchi, Masakazu Toi, Kaori Togashi
Purpose To investigate the performance of integrated approaches that combined intravoxel incoherent motion (IVIM) and non-Gaussian diffusion parameters compared with the Breast Imaging and Reporting Data System (BI-RADS) to establish multiparameter thresholds scores or probabilities by using Bayesian analysis to distinguish malignant from benign breast lesions and their correlation with molecular prognostic factors. Materials and Methods Between May 2013 and March 2015, 411 patients were prospectively enrolled and 199 patients (allocated to training [n = 99] and validation [n = 100] sets) were included in this study...
November 2, 2017: Radiology
https://www.readbyqxmd.com/read/29095055/diffusion-mri-findings-in-patients-with-extensive-and-minimal-post-concussion-symptoms-after-mtbi-and-healthy-controls-a-cross-sectional-study
#11
Erhard Trillingsgaard Næss-Schmidt, Jakob Udby Blicher, Anna Tietze, Charlotte Ulrikka Rask, Susanne Wulff Svendsen, Andreas Schröder, Mille Møller Thastum, Astrid Høeg Tuborgh, Oana-Veronica Frederiksen, Leif Østergaard, Simon Fristed Eskildsen, Brian Hansen, Sune Jespersen, Jørgen Feldbæk Nielsen
PRIMARY OBJECTIVES: We hypothesized that the microstructure of the corpus callosum, thalamus and hippocampus, as measured with diffusion and Mean of the Kurtosis Tensor (MKT) MRI, differs between healthy subjects and patients with extensive and minimal post-concussion symptoms (PCS) and that MKT measures correlate with PCS severity and self-reported cognitive symptoms. RESEARCH DESIGN: A cross-sectional study comparing patients with extensive PCS and patients with minimal PCS 2-5 months after mild traumatic brain injury (mTBI) with each other and with an external healthy control group...
November 2, 2017: Brain Injury: [BI]
https://www.readbyqxmd.com/read/29093289/effect-of-magnesium-stearate-mono-and-dihydrate-dispersibilities-on-physical-properties-of-tablets
#12
Koji Yamamoto, Taisuke Tamura, Yasuo Yoshihashi, Katsuhide Terada, Etsuo Yonemochi
Magnesium stearate (MgSt), an essential lubricant in the manufacturing of tablets, is available in several hydrate forms with different qualities that affect the physical properties of tablets. This study examined MgSt mono- and dihydrates, and their effects on tablet dissolution, disintegration, and hardness. These effects were examined in terms of surface free energy and dispersibility. Dissolution, disintegration, and hardness were evaluated for tablets manufactured from powder mixtures of each MgSt hydrate form and other components, including ethenzamide as an active ingredient, using different mixing times...
2017: Chemical & Pharmaceutical Bulletin
https://www.readbyqxmd.com/read/29090485/fisher-information-and-cram%C3%A3-r-rao-lower-bound-for-experimental-design-in-parallel-imaging
#13
Mustapha Bouhrara, Richard G Spencer
PURPOSE: The Cramér-Rao lower bound (CRLB) is widely used in the design of magnetic resonance (MR) experiments for parameter estimation. Previous work has considered only Gaussian or Rician noise distributions in this calculation. However, the noise distribution for multi-coil acquisitions, such as in parallel imaging, obeys the noncentral χ-distribution under many circumstances. The purpose of this paper is to present the CRLB calculation for parameter estimation from multi-coil acquisitions...
November 1, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29075561/using-machine-learning-to-classify-temporal-lobe-epilepsy-based-on-diffusion-mri
#14
John Del Gaizo, Neda Mofrad, Jens H Jensen, David Clark, Russell Glenn, Joseph Helpern, Leonardo Bonilha
BACKGROUND: It is common for patients diagnosed with medial temporal lobe epilepsy (TLE) to have extrahippocampal damage. However, it is unclear whether microstructural extrahippocampal abnormalities are consistent enough to enable classification using diffusion MRI imaging. Therefore, we implemented a support vector machine (SVM)-based method to predict TLE from three different imaging modalities: mean kurtosis (MK), mean diffusivity (MD), and fractional anisotropy (FA). While MD and FA can be calculated from traditional diffusion tensor imaging (DTI), MK requires diffusion kurtosis imaging (DKI)...
October 2017: Brain and Behavior
https://www.readbyqxmd.com/read/29063250/whole-tumour-diffusion-kurtosis-mr-imaging-histogram-analysis-of-rectal-adenocarcinoma-correlation-with-clinical-pathologic-prognostic-factors
#15
Yanfen Cui, Xiaotang Yang, Xiaosong Du, Zhizheng Zhuo, Lei Xin, Xintao Cheng
OBJECTIVE: To investigate potential relationships between diffusion kurtosis imaging (DKI)-derived parameters using whole-tumour volume histogram analysis and clinicopathological prognostic factors in patients with rectal adenocarcinoma. MATERIAL AND METHODS: 79 consecutive patients who underwent MRI examination with rectal adenocarcinoma were retrospectively evaluated. Parameters D, K and conventional ADC were measured using whole-tumour volume histogram analysis...
October 23, 2017: European Radiology
https://www.readbyqxmd.com/read/29060517/respiratory-sounds-classification-using-statistical-biomarker
#16
Ashok Mondal, Hong Tang
In this paper, we have proposed a new feature extraction technique based on statistical morphology of lung sound signal (LS). This work attempts to (i) generate certain intrinsic mode functions (IMFs), (ii) select a set of informative IMFs and (iii) extract relevant features from the selected IMFs and residue. Feature vector is formed by using the higher order moments: mean, standard deviation, skewness and kurtosis and employed as input to the classifier models for classification of three types of LS signals: crackle, wheeze and normal...
July 2017: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/29060477/reliable-gradient-search-directions-for-kurtosis-based-deflationary-ica-application-to-physiological-signal-processing
#17
M Saleh, A Karfoul, A Kachenoura, L Senhadji, L Albera
Efficient gradient search directions for the optimisation of the kurtosis-based deflationary RobustICA algorithm in the case of real-valued data are proposed in this paper. The proposed scheme employs, in the gradient-like algorithm typically used to optimise the considered kurtosis-based objective function, search directions computed from a more reliable approximation of the negentropy than the kurtosis. The proposed scheme inherits the exact line search of the conventional RobustICA for which a good convergence property through a given direction is guaranteed...
July 2017: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/29060246/the-use-of-subject-specific-finite-element-analysis-of-l1-l4-vertebra-to-screening-osteoporosis-in-postmenopausal-women
#18
Elena Alacreu, Estanislao Arana, David Moratal
The aim of this work is to study Computed Tomography (CT)-based Finite Element (FE) modelling of lumbar vertebra to classify osteoporotic patients using dual-energy x-ray absorptiometry (DXA) as reference. Cohort comprised 15 postmenopausal female patients with CT-DXA pairs. Sixty subject-specific CT-based FE models were constructed of L1 to L4 vertebrae. Load-displacement in each node of the models was analyzed. Mean kurtosis values of displacement distributions between osteoporosis and healthy groups at L1 level showed a statistically significant difference (p<;0...
July 2017: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/29060241/motion-artifact-reduction-in-photoplethysmogram-signals-based-on-periodic-component-factorization
#19
Frank P-W Lo, Charles X-T Li, Jiankun Wang, Max Q-H Meng
Continuous blood pressure measurement based on pulse transit time (PTT) is a deeply research topic over recent decades. Advanced algorithms have been proposed by scholars to give satisfactory estimation in stationary position. Nevertheless, pulse transit time (PTT) is shown to be strongly affected by hand movement and the estimation of blood pressure is no longer accurate under strenuous exercise. Because of this, a novel algorithm called Periodic Component Factorization (PCF), which is an extension of Independent Component Analysis (ICA), for better removal of motion artifact (MA) from photoplethysmography (PPG) signals is proposed in this paper...
July 2017: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/29050274/apparent-diffusion-coefficient-histogram-analysis-can-evaluate-radiation-induced-parotid-damage-and-predict-late-xerostomia-degree-in-nasopharyngeal-carcinoma
#20
Nan Zhou, Tingting Guo, Huanhuan Zheng, Xia Pan, Chen Chu, Xin Dou, Ming Li, Song Liu, Lijing Zhu, Baorui Liu, Weibo Chen, Jian He, Jing Yan, Zhengyang Zhou, Xiaofeng Yang
We investigated apparent diffusion coefficient (ADC) histogram analysis to evaluate radiation-induced parotid damage and predict xerostomia degrees in nasopharyngeal carcinoma (NPC) patients receiving radiotherapy. The imaging of bilateral parotid glands in NPC patients was conducted 2 weeks before radiotherapy (time point 1), one month after radiotherapy (time point 2), and four months after radiotherapy (time point 3). From time point 1 to 2, parotid volume, skewness, and kurtosis decreased (P < 0.001, = 0...
September 19, 2017: Oncotarget
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