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https://www.readbyqxmd.com/read/29352378/can-histogram-analysis-of-mr-images-predict-aggressiveness-in-pancreatic-neuroendocrine-tumors
#1
Riccardo De Robertis, Bogdan Maris, Nicolò Cardobi, Paolo Tinazzi Martini, Stefano Gobbo, Paola Capelli, Silvia Ortolani, Sara Cingarlini, Salvatore Paiella, Luca Landoni, Giovanni Butturini, Paolo Regi, Aldo Scarpa, Giampaolo Tortora, Mirko D'Onofrio
OBJECTIVES: To evaluate MRI derived whole-tumour histogram analysis parameters in predicting pancreatic neuroendocrine neoplasm (panNEN) grade and aggressiveness. METHODS: Pre-operative MR of 42 consecutive patients with panNEN >1 cm were retrospectively analysed. T1-/T2-weighted images and ADC maps were analysed. Histogram-derived parameters were compared to histopathological features using the Mann-Whitney U test. Diagnostic accuracy was assessed by ROC-AUC analysis; sensitivity and specificity were assessed for each histogram parameter...
January 19, 2018: European Radiology
https://www.readbyqxmd.com/read/29347497/statistical-characterization-of-discrete-conservative-systems-the-web-map
#2
Guiomar Ruiz, Ugur Tirnakli, Ernesto P Borges, Constantino Tsallis
We numerically study the two-dimensional, area preserving, web map. When the map is governed by ergodic behavior, it is, as expected, correctly described by Boltzmann-Gibbs statistics, based on the additive entropic functional S_{BG}[p(x)]=-k∫dxp(x)lnp(x). In contrast, possible ergodicity breakdown and transitory sticky dynamical behavior drag the map into the realm of generalized q statistics, based on the nonadditive entropic functional S_{q}[p(x)]=k1-∫dx[p(x)]^{q}/q-1 (q∈R;S_{1}=S_{BG}). We statistically describe the system (probability distribution of the sum of successive iterates, sensitivity to the initial condition, and entropy production per unit time) for typical values of the parameter that controls the ergodicity of the map...
October 2017: Physical Review. E
https://www.readbyqxmd.com/read/29345431/the-effect-of-diuresis-on-extravascular-lung-water-and-pulmonary-function-in-acute-decompensated-heart-failure
#3
Steven C Chase, Caitlin C Fermoyle, Courtney M Wheatley, Jacob J Schaefer, Lyle J Olson, Bruce D Johnson
AIMS: The effect of extravascular lung water (EVLW) and relationship to functional status as a result of acute decompensated heart failure (ADHF) are not well understood. We sought to quantify changes in clinical variables, EVLW, airway anatomy, spirometry, and diffusing capacity for carbon monoxide before and after treatment for ADHF. METHODS AND RESULTS: Fifteen patients were recruited within 24 h of hospital admission. Spirometry, diffusing capacity for carbon monoxide, and surrogates of EVLW by computed tomography were measured and were then repeated within 24 h of discharge...
January 18, 2018: ESC Heart Failure
https://www.readbyqxmd.com/read/29344733/linking-intraspecific-trait-variability-and-spatial-patterns-of-subtropical-trees
#4
En-Rong Yan, Liu-Li Zhou, Han Y H Chen, Xi-Hua Wang, Xiang-Yu Liu
The importance of intraspecific trait variability (ITV) to the spatial distribution of individual species is unclear. We hypothesized that intraspecific trait dispersions underlying niche processes deviate more from null model expectations, by reducing their spread (range and variance), kurtosis, and standard deviation of near-neighbor distance, for species with aggregated than those with random distributions. The link between species' spatial distributions and ITV patterns was examined using an individual tree-based trait data set, in which specific leaf area, mean leaf area, leaf dry matter content, and diameter at breast height were measured for 18,773 stems of 45 species in a 4...
January 17, 2018: Oecologia
https://www.readbyqxmd.com/read/29332859/grading-fatty-liver-by-ultrasound-time-domain-radiofrequency-signal-analysis-an-in-vivo-study-of-rats
#5
Wenwu Ling, Jierong Quan, Jiangli Lin, Tingting Qiu, Jiawu Li, Qiang Lu, Changli Lu, Yan Luo
This study aimed to assess the severity of fatty liver (FL) by analyzing ultrasound radiofrequency (RF) signals in rats. One hundred and twenty rats (72 in the FL group and 48 in the control group) were used for this purpose. Histological results were the golden standard: 42 cases had normal livers (N), 30 cases had mild FL (L1), 25 cases had moderate FL (L2), 13 cases presented with severe FL (L3), and 10 cases were excluded from the study. Four RF parameters (Mean, Mean/SD ratio [MSR], skewness [SK], and kurtosis [KU] were extracted...
January 12, 2018: Experimental Animals
https://www.readbyqxmd.com/read/29332011/examining-the-utility-of-cystatin-c-as-a-confirmatory-test-of-chronic-kidney-disease-across-the-age-range-in-middle-aged-and-older-community-dwelling-adults
#6
Mark Canney, Donal J Sexton, Neil O'Leary, Martin Healy, Rose Anne Kenny, Mark A Little, Conall M O'Seaghdha
BACKGROUND: Cystatin C has been proposed as a confirmatory test of chronic kidney disease (CKD). This is most applicable to older individuals with CKD, the majority of whom have a creatinine-based estimated glomerular filtration rate (eGFR) of 45-59 mL/min/1.73 m2 (CKD stage 3a). We sought to examine the utility of cystatin C as a confirmatory test of CKD across the age range in the general population of older adults. METHODS: Cross-sectional analysis of 5386 participants from The Irish Longitudinal Study on Ageing, a cluster-sampled national cohort of community-dwelling adults aged ≥50 years...
January 13, 2018: Journal of Epidemiology and Community Health
https://www.readbyqxmd.com/read/29331362/multi-model-analysis-of-diffusion-weighted-imaging-of-normal-testes-at-3-0-t-preliminary-findings
#7
Xiangde Min, Zhaoyan Feng, Liang Wang, Jie Cai, Basen Li, Zan Ke, Peipei Zhang, Huijuan You, Xu Yan
RATIONALE AND OBJECTIVES: This study aimed to establish diffusion quantitative parameters (apparent diffusion coefficient [ADC], DDC, α, Dapp, and Kapp) in normal testes at 3.0 T. MATERIALS AND METHODS: Sixty-four healthy volunteers in two age groups (A: 10-39 years; B: ≥ 40 years) underwent diffusion-weighted imaging scanning at 3.0 T. ADC1000, ADC2000, ADC3000, DDC, α, Dapp, and Kapp were calculated using the mono-exponential, stretched-exponential, and kurtosis models...
January 10, 2018: Academic Radiology
https://www.readbyqxmd.com/read/29321645/mri-features-predictive-of-negative-surgical-margins-in-patients-with-her2-overexpressing-breast-cancer-undergoing-breast-conservation
#8
Brittany Z Dashevsky, Jung Hun Oh, Aditya P Apte, Blanca Bernard-Davila, Elizabeth A Morris, Joseph O Deasy, Elizabeth J Sutton
Here we develop a tool to predict resectability of HER2+ breast cancer at breast conservation surgery (BCS) utilizing features identified on preoperative breast MRI. We identified patients with HER2+ breast cancer who obtained pre-operative breast MRI and underwent BCS between 2002-2013. From the contoured tumor on pre-operative MRI, shape, histogram, and co-occurrence and size zone matrix texture features were extracted. In univariate analysis, Spearman's correlation coefficient (Rs) was used to assess the correlation between each image feature and an endpoint (surgical re-excision)...
January 10, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29317047/histogram-analysis-of-greyscale-sonograms-to-differentiate-between-the-subtypes-of-follicular-variant-of-papillary-thyroid-cancer
#9
M-R Kwon, J H Shin, S Y Hahn, Y L Oh, J Y Kwak, E Lee, Y Lim
AIM: To evaluate the diagnostic value of histogram analysis using ultrasound (US) to differentiate between the subtypes of follicular variant of papillary thyroid carcinoma (FVPTC). MATERIALS AND METHODS: The present study included 151 patients with surgically confirmed FVPTC diagnosed between January 2014 and May 2016. Their preoperative US features were reviewed retrospectively. Histogram parameters (mean, maximum, minimum, range, root mean square, skewness, kurtosis, energy, entropy, and correlation) were obtained for each nodule...
January 6, 2018: Clinical Radiology
https://www.readbyqxmd.com/read/29307077/analysis-of-ct-features-and-quantitative-texture-analysis-in-patients-with-thymic-tumors-correlation-with-grading-and-staging
#10
Angelo Iannarelli, Beatrice Sacconi, Francesca Tomei, Marco Anile, Flavia Longo, Mario Bezzi, Alessandro Napoli, Luca Saba, Michele Anzidei, Giulia D'Ovidio, Roberto Scipione, Carlo Catalano
OBJECTIVES: To evaluate potential relationship between qualitative CT features, quantitative texture analysis (QTA), histology, WHO staging, Masaoka classification and myasthenic syndrome in patients with thymic tumors. MATERIALS AND METHODS: Sixteen patients affected by histologically proven thymic tumors were retrospectively included in the study population. Clinical information, with special regard to myasthenic syndrome and serological positivity of anti-AchR antibodies, were recorded...
January 6, 2018: La Radiologia Medica
https://www.readbyqxmd.com/read/29306048/comparison-of-cumulant-expansion-and-q-space-imaging-estimates-for-diffusional-kurtosis-in-brain
#11
Vaibhav Mohanty, Emilie T McKinnon, Joseph A Helpern, Jens H Jensen
PURPOSE: To compare estimates for the diffusional kurtosis in brain as obtained from a cumulant expansion (CE) of the diffusion MRI (dMRI) signal and from q-space (QS) imaging. THEORY AND METHODS: For the CE estimates of the kurtosis, the CE was truncated to quadratic order in the b-value and fit to the dMRI signal for b-values from 0 up to 2000s/mm2. For the QS estimates, b-values ranging from 0 up to 10,000s/mm2 were used to determine the diffusion displacement probability density function (dPDF) via Stejskal's formula...
January 3, 2018: Magnetic Resonance Imaging
https://www.readbyqxmd.com/read/29305126/assessing-diffusion-kurtosis-tensor-estimation-methods-using-a-digital-brain-phantom-derived-from-human-connectome-project-data
#12
Daniel V Olson, Volkan Arpinar, L Tugan Muftuler
PURPOSE: Diffusion kurtosis imaging (DKI) has gained popularity in recent years as an advanced diffusion-weighted MRI technique. This work aims to quantitatively compare the performance and accuracy of four DKI processing algorithms. For this purpose, a digital DKI brain phantom is developed. METHODS: Data from the Human Connectome Project database were used to generate a DKI digital phantom. In a Monte Carlo Rician noise simulation, four DKI processing algorithms were compared based on their mean square error, squared bias, and variance...
January 2, 2018: Magnetic Resonance Imaging
https://www.readbyqxmd.com/read/29295753/differentiation-between-malignant-and-benign-breast-masses-combination-of-semi-quantitative-analysis-on-dce-mri-and-histogram-analysis-of-adc-maps
#13
H-L Liu, M Zong, H Wei, J-J Lou, S-Q Wang, Q-G Zou, H-B Shi, Y-N Jiang
AIM: To investigate the performance of combined semi-quantitative analysis on dynamic contrast enhanced (DCE) magnetic resonance imaging (MRI) and histogram analysis of diffusion-weighted imaging (DWI) for distinguishing malignant from benign breast masses. MATERIALS AND METHODS: This study included 178 patients with breast masses (benign:malignant=88:9) who underwent both DCE-MRI and DWI. The semi-quantitative parameters, derived from DCE-MRI, included maximum slope of increase (MSI), signal intensity slope (SIslope), initial percentage of enhancement (Einitial), percentage of peak enhancement (Epeak), early signal enhancement ratio (ESER), and second enhancement percentage (SEP)...
December 30, 2017: Clinical Radiology
https://www.readbyqxmd.com/read/29288891/thermal-heterogeneity-within-aqueous-materials-quantified-by-1h-nmr-spectroscopy-multiparametric-validation-in-silico-and-in-vitro
#14
Norbert W Lutz, Monique Bernard
We recently suggested a new paradigm for statistical analysis of thermal heterogeneity in (semi-)aqueous materials by 1H NMR spectroscopy, using water as a temperature probe. Here, we present a comprehensive in silico and in vitro validation that demonstrates the ability of this new technique to provide accurate quantitative parameters characterizing the statistical distribution of temperature values in a volume of (semi-)aqueous matter. First, line shape parameters of numerically simulated water 1H NMR spectra are systematically varied to study a range of mathematically well-defined temperature distributions...
December 21, 2017: Journal of Magnetic Resonance
https://www.readbyqxmd.com/read/29279171/support-vector-machines-svm-classification-of-prostate-cancer-gleason-score-in-central-gland-using-multiparametric-magnetic-resonance-images-a-cross-validated-study
#15
Jiance Li, Zhiliang Weng, Huazhi Xu, Zhao Zhang, Haiwei Miao, Wei Chen, Zheng Liu, Xiaoqin Zhang, Meihao Wang, Xiao Xu, Qiong Ye
PURPOSE: To assess the performance of Support Vector Machines (SVM) classification to stratify the Gleason Score (GS) of prostate cancer (PCa) in the central gland (CG) based on image features across multiparametric magnetic resonance imaging (mpMRI). MATERIALS AND METHODS: This retrospective study was approved by the institutional review board, and informed consent was waived. One hundred fifty-two CG cancerous ROIs were identified through radiological-pathological correlation...
January 2018: European Journal of Radiology
https://www.readbyqxmd.com/read/29279166/characterization-of-testicular-germ-cell-tumors-whole-lesion-histogram-analysis-of-the-apparent-diffusion-coefficient-at-3t
#16
Xiangde Min, Zhaoyan Feng, Liang Wang, Jie Cai, Xu Yan, Basen Li, Zan Ke, Peipei Zhang, Huijuan You
PURPOSE: To assess the values of parameters derived from whole-lesion histograms of the apparent diffusion coefficient (ADC) at 3T for the characterization of testicular germ cell tumors (TGCTs). MATERIALS AND METHODS: A total of 24 men with TGCTs underwent 3T diffusion-weighted imaging. Fourteen tumors were pathologically confirmed as seminomas, and ten tumors were pathologically confirmed as nonseminomas. Whole-lesion histogram analysis of the ADC values was performed...
January 2018: European Journal of Radiology
https://www.readbyqxmd.com/read/29277719/miniature-pig-model-of-human-adolescent-brain-white-matter-development
#17
Meghann C Ryan, Paul Sherman, Laura M Rowland, S Andrea Wijtenburg, Ashley Acheson, Els Fieremans, Jelle Veraart, Dmitry Novikov, L Elliot Hong, John Sladky, P Dana Peralta, Peter Kochunov, Stephen A McGuire
BACKGROUND: Neuroscience research in brain development and disorders can benefit from an in vivo animal model that portrays normal white matter (WM) development trajectories and has a sufficiently large cerebrum for imaging with human MRI scanners and protocols. NEW METHOD: Twelve three-month-old Sinclair™ miniature pigs (Sus scrofa domestica) were longitudinally evaluated during adolescent development using advanced diffusion weighted imaging (DWI) focused on cerebral WM...
December 22, 2017: Journal of Neuroscience Methods
https://www.readbyqxmd.com/read/29275590/-parkinson-s-disease-diffusion-kurtosis-imaging-and-the-correlation-with-clinical-manifestations
#18
Y Q Sun, Q Zhang, Z Jiang, C Y Zhang, J W Zhang, H Chen, J K Shen
Objective: Using magnetic resonance diffusion kurtosis imaging (DKI) to evaluate the microstructure changes of deep brain nucleus in Parkinson's disease (PD) as well as the correlation with clinical manifestations. Methods: Thirty-two PD patients were recruited into this study. Twenty gender and age matched healthy subjects served as the control group. All participants underwent MRI examinations, including T(1)WI, T(2)WI, DWI, susceptibility weighted imaging (SWI) and DKI. The original DKI imaging data were processed offline to calculate two parametric maps, including mean kurtosis (MK) value and fractional anisotropy (FA) value...
December 5, 2017: Zhonghua Yi Xue za Zhi [Chinese medical journal]
https://www.readbyqxmd.com/read/29274016/quantitative-pulmonary-blood-flow-measurement-using-15o-h2o-pet-with-and-without-tissue-fraction-correction-a-comparison-study
#19
Keiko Matsunaga, Masahiro Yanagawa, Tomoyuki Otsuka, Haruhiko Hirata, Takashi Kijima, Atsushi Kumanogoh, Noriyuki Tomiyama, Eku Shimosegawa, Jun Hatazawa
BACKGROUND: Physiological measures per lung parenchyma, rather than per lung volume, sometimes reflect the disease status. PET images of the lung, which are usually expressed per lung volume, could confound the interpretation of the disease status, especially in cases with a prominent heterogeneity in aeration. The aim of the present study was to develop a method for measuring pulmonary blood flow (PBF) with aeration correction using 15O-H2O PET and to compare the results with those obtained using a conventional method...
December 22, 2017: EJNMMI Research
https://www.readbyqxmd.com/read/29273964/hrct-texture-analysis-for-pure-or-part-solid-ground-glass-nodules-distinguishability-of-adenocarcinoma-in-situ-or-minimally-invasive-adenocarcinoma-from-invasive-adenocarcinoma
#20
Takuya Yagi, Motohiko Yamazaki, Riuko Ohashi, Rei Ogawa, Hiroyuki Ishikawa, Norihiko Yoshimura, Masanori Tsuchida, Yoichi Ajioka, Hidefumi Aoyama
PURPOSE: To distinguish between adenocarcinoma in situ (AIS)-minimally invasive adenocarcinoma (MIA) and invasive adenocarcinoma (IAC) showing pure or part-solid ground-glass nodules (GGNs) by high-resolution computed tomography (HRCT) texture analysis. MATERIALS AND METHODS: This retrospective study included 101 consecutive patients with 115 pure or part-solid GGNs ≤ 3 cm diameter, which were surgically resected and pathologically diagnosed with AIS, MIA, or IAC (48 AIS-MIA and 67 IAC) between April 2011 and March 2015...
December 22, 2017: Japanese Journal of Radiology
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