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https://www.readbyqxmd.com/read/28101424/detection-and-classification-of-three-class-initial-dips-from-prefrontal-cortex
#1
Amad Zafar, Keum-Shik Hong
In this paper, the use of initial dips using functional near-infrared spectroscopy (fNIRS) for brain-computer interface (BCI) is investigated. Features and window sizes for detecting initial dips are also discussed. Three mental tasks including mental arithmetic, mental counting, and puzzle solving are performed in obtaining fNIRS signals from the prefrontal cortex. Vector-based phase analysis method combined with a threshold circle, as a decision criterion, are used to detect the initial dips. Eight healthy subjects participate in experiment...
January 1, 2017: Biomedical Optics Express
https://www.readbyqxmd.com/read/28090658/analysis-of-the-effects-of-noise-dwi-sampling-and-value-of-assumed-parameters-in-diffusion-mri-models
#2
Elizabeth B Hutchinson, Alexandru V Avram, M Okan Irfanoglu, C Guan Koay, Alan S Barnett, Michal E Komlosh, Evren Özarslan, Susan C Schwerin, Sharon L Juliano, Carlo Pierpaoli
PURPOSE: This study was a systematic evaluation across different and prominent diffusion MRI models to better understand the ways in which scalar metrics are influenced by experimental factors, including experimental design (diffusion-weighted imaging [DWI] sampling) and noise. METHODS: Four diffusion MRI models-diffusion tensor imaging (DTI), diffusion kurtosis imaging (DKI), mean apparent propagator MRI (MAP-MRI), and neurite orientation dispersion and density imaging (NODDI)-were evaluated by comparing maps and histogram values of the scalar metrics generated using DWI datasets obtained in fixed mouse brain with different noise levels and DWI sampling complexity...
January 16, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28076867/identifying-host-genetic-variants-associated-with-microbiome-composition-by-testing-multiple-beta-diversity-matrices
#3
Xing Hua, James J Goedert, Maria Teresa Landi, Jianxin Shi
OBJECTIVES: Host genetics have been recently reported to affect human microbiome composition. We previously developed a statistical framework, microbiomeGWAS, to identify host genetic variants associated with microbiome composition by testing a distance matrix. However, statistical power depends on the choice of a microbiome distance matrix. To achieve more robust statistical power, we aim to extend microbiomeGWAS to test the association with many distance matrices, which are defined based on multilevel taxa abundances and phylogenetic information...
2016: Human Heredity
https://www.readbyqxmd.com/read/28068586/preliminary-investigation-of-whole-pancreas-3d-histogram-adc-metrics-for-predicting-progression-of-acute-pancreatitis
#4
Amir K Iranmahbook, Andrea S Kierans, Chenchan Huang, Justin M Ream, Andrew B Rosenkrantz
PURPOSE: To evaluate whole-pancreas 3D-histogram ADC metrics in acute pancreatitis. METHODS: In 41 patients with acute pancreatitis undergoing MRI/MRCP with DWI, 3D-volumes-of-interest encompassing the entire pancreas were placed to derive whole-pancreas histogram ADC metrics. RESULTS: There were trends toward higher 0-10th percentile ADC, higher 10-25th percentile ADC, lower skewness, and higher kurtosis in patients with new complications (p=0...
December 21, 2016: Clinical Imaging
https://www.readbyqxmd.com/read/28068363/quantitative-computed-tomography-features-for-predicting-tumor-recurrence-in-patients-with-surgically-resected-adenocarcinoma-of-the-lung
#5
Hyun Jung Koo, Yu Sub Sung, Woo Hyun Shim, Hai Xu, Chang-Min Choi, Hyeong Ryul Kim, Jung Bok Lee, Mi Young Kim
PURPOSE: The purpose of this study was to determine if preoperative quantitative computed tomography (CT) features including texture and histogram analysis measurements are associated with tumor recurrence in patients with surgically resected adenocarcinoma of the lung. METHODS: The study included 194 patients with surgically resected lung adenocarcinoma who underwent preoperative CT between January 2013 and December 2013. Quantitative CT feature analysis of the lung adenocarcinomas were performed using in-house software based on plug-in package for ImageJ...
2017: PloS One
https://www.readbyqxmd.com/read/28061379/assessment-of-the-non-gaussianity-and-non-linearity-levels-of-simulated-semg-signals-on-stationary-segments
#6
Noureddine Messaoudi, Raïs El'hadi Bekka, Philippe Ravier, Rachid Harba
The purpose of this paper was to evaluate the effects of the longitudinal single differential (LSD), the longitudinal double differential (LDD) and the normal double differential (NDD) spatial filters, the electrode shape, the inter-electrode distance (IED) on non-Gaussianity and non-linearity levels of simulated surface EMG (sEMG) signals when the maximum voluntary contraction (MVC) varied from 10% to 100% by a step of 10%. The effects of recruitment range thresholds (RR), the firing rate (FR) strategy and the peak firing rate (PFR) of motor units were also considered...
December 25, 2016: Journal of Electromyography and Kinesiology
https://www.readbyqxmd.com/read/28057085/3d-analysis-of-apparent-diffusion-coefficient-histograms-in-hepatocellular-carcinoma-correlation-with-histological-grade
#7
Tomohisa Moriya, Kazuhiro Saito, Yu Tajima, Taiyo L Harada, Yoichi Araki, Katsutoshi Sugimoto, Koichi Tokuuye
BACKGROUND: To evaluate the usefulness of differentiation of histological grade in hepatocellular carcinoma (HCC) using three-dimensional (3D) analysis of apparent diffusion coefficient (ADC) histograms retrospectively. METHODS: The subjects consisted of 53 patients with 56 HCCs. The subjects included 12 well-differentiated, 35 moderately differentiated, and nine poorly differentiated HCCs. Diffusion-weighted imaging (b-values of 100 and 800 s/mm(2)) were obtained within 3 months before surgery...
January 5, 2017: Cancer Imaging: the Official Publication of the International Cancer Imaging Society
https://www.readbyqxmd.com/read/28055267/microstructural-changes-in-the-thalamus-after-mild-traumatic-brain-injury-a-longitudinal-diffusion-and-mean-kurtosis-tensor-mri-study
#8
Erhard Trillingsgaard Næss-Schmidt, Jakob Udby Blicher, Simon Fristed Eskildsen, Anna Tietze, Brian Hansen, Peter William Stubbs, Sune Jespersen, Leif Østergaard, Jørgen Feldbæk Nielsen
PRIMARY OBJECTIVE: The primary aim of this study was to assess microstructural changes in the thalamus, hippocampus and corpus callosum with a fast mean kurtosis tensor (MKT) technique, in the acute and sub-acute phase after mTBI. It was hypothesized that MKT would differ between baseline and follow-up in patients. The secondary aim was to relate diffusion measures to symptoms of mTBI. RESEARCH DESIGN: A longitudinal case-control study. METHODS AND PROCEDURES: Twenty-seven patients with mTBI and 27 age- and gender-matched healthy controls were enrolled in the study...
January 5, 2017: Brain Injury: [BI]
https://www.readbyqxmd.com/read/28054731/lung-adenocarcinoma-assessment-of-epidermal-growth-factor-receptor-mutation-status-based-on-extended-models-of-diffusion-weighted-image
#9
Mei Yuan, Xue-Hui Pu, Xiao-Quan Xu, Yu-Dong Zhang, Yan Zhong, Hai Li, Jiang-Fen Wu, Tong-Fu Yu
PURPOSE: To evaluate the diagnostic performance of extended models of diffusion-weighted (DW) imaging to help differentiate the epidermal growth factor receptor (EGFR) mutation status in stage IIIA-IV lung adenocarcinoma. MATERIALS AND METHODS: This retrospective study had institutional research board approval and was HIPAA compliant. Preoperative extended DW imaging including intravoxel incoherent motion (IVIM) and diffusional kurtosis imaging (DKI) 3 Tesla MRI were retrospectively evaluated in 53 patients with pathologically confirmed non-early stage (IIIA-IV) lung adenocarcinoma...
January 5, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28048644/tu-h-campus-iep3-05-computer-aided-diagnosis-employing-automatically-segmented-color-specific-regions-in-ultrasound-shear-wave-elastography-for-the-assessment-of-chronic-liver-disease
#10
I Gatos, S Tsantis, G C Kagadis
PURPOSE: To assess the role of an automated Computer Aided Diagnosis (CAD) system in differentiation of Healthy Subjects to Chronic Liver Disease (CLD) Patients in terms of liver fibrosis (F0-F4), using Ultrasound Shear Wave Elastography (SWE). METHODS: Clinical Dataset consisted of 125 subjects, 55 Healthy (F0) whom condition was validated with Normal Biochemical Markers and clear Clinical History, and 70 with CLD (F1-F4) whom condition was validated with Liver Biopsy...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048552/su-f-t-407-artifact-reduction-with-dual-energy-or-imar-who-s-winning
#11
E Elder, E Schreibmann, A Dhabaan
PURPOSE: The purpose of this abstract was to evaluate the performance of commercial strategies for artifact reduction in radiation oncology settings. The iterative metal artifact reduction (Siemens iMAR) algorithm and monoenergetic virtual datasets reconstructed from dual energy scans are compared side-by-side in their ability to image in the presence of metal inserts. METHODS: A CIRS ATOM Dosimetry Verification Phantom was scanned with and without a metal insert on a SOMATOM Definition AS dual energy scanner...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048488/su-f-t-602-central-moments-to-analyze-dose-distributions-in-planning-target-volumes
#12
Q Zhang, Y Cao, A Jamshidi, P Vigneri, L Potters, E Klein
PURPOSE: To quantify the dose distribution inside planning target volumes (PTV), the coefficient of variation, skewness (third central moment) and kurtosis (fourth central moment) were used to analyze the dose distributions of PTVs for lung and prostate cases. Those variables can be used to measure the shape of the dose distribution. METHODS: The mean dose, coefficient of variation, skewness, and kurtosis were used to analyze the dose distributions inside PTVs for 24 randomly selected patients...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048190/su-f-r-19-novel-radiomics-quantifying-tumor-structural-evolution-using-deformation-vector-field-application-for-tumor-response-assessment
#13
S Riyahi, W Choi, W Lu
PURPOSE: to quantify tumor volume/shape evolution due to chemoradiotherapy using structural evolution maps computed from deformation field. To extract radiomics from these maps for tumor response assessment. METHODS: In 20 patients with esophageal cancer, BSpline deformable registration was performed to register post-treatment CT image to pre-treatment CT image. The resulting deformation (vector) field represented tissue displacement at every voxel. We computed three structural evolution maps from the deformation field: (1) contraction map, to detect local tumor shrinking/growth, (2) Jacobian map, to characterize the ratio of local volumetric variation, and (3) Hessian map, to track dynamic evolving process...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048179/su-f-r-54-ct-texture-based-early-tumor-treatment-response-assessment-during-radiation-therapy-delivery-small-cell-versus-non-small-cell-lung-cancers
#14
J Paul, E Gore, X Li
PURPOSE: Tumor treatment response may potentially be assessed during radiation therapy (RT) by analyzing changes in CT-textures. We investigated the different early RT-responses between small cell (SCLC) and non-small cell lung cancer (NSCLC) as assessed by CT-texture. METHODS: Daily diagnostic-quality CT acquired during routine CT-guided RT using a CT-on-Rails for 13-NSCLC and 5-SCLC patients were analyzed. These patient had ages ranging from 45-78 and 38-63 years, respectively, for NSCLC and SCLC groups, and tumor-stages ranging from T2-T4, and were treated with either RT or chemotherapy and RT with 45-66Gy/ 20-34 fractions...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048125/su-f-r-31-identification-of-robust-normal-lung-ct-texture-features-for-the-prediction-of-radiation-induced-lung-disease
#15
W Choi, S Riyahi, W Lu
PURPOSE: Normal lung CT texture features have been used for the prediction of radiation-induced lung disease (radiation pneumonitis and radiation fibrosis). For these features to be clinically useful, they need to be relatively invariant (robust) to tumor size and not correlated with normal lung volume. METHODS: The free-breathing CTs of 14 lung SBRT patients were studied. Different sizes of GTVs were simulated with spheres placed at the upper lobe and lower lobe respectively in the normal lung (contralateral to tumor)...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048092/su-g-iep1-10-permeability-evaluation-of-interstitial-cystitis-by-dce-mri-of-the-bladder
#16
D Wu, J Vo, J North, R Towner, R Hurst
PURPOSE: Interstitial cystitis (IC) is a chronic and painful condition that can lead to bladder pain syndrome (BPS) in women. IC and BPS have been known to manifest after physiological changes after giving birth. In this project, we pioneered and advanced a new clinical utility using DCE-MRI to assess bladder permeability. At first IC/BPS perfusion methods were with ratio signal evaluation, we now incorporate pharmacokinetics techniques to allow for further assessment. METHODS: In this pilot study, female patients and volunteers (IC=4, Control=3) underwent imaging with a clinical GE 3T 750W MRI system...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048091/su-f-r-50-radiation-induced-changes-in-ct-number-histogram-during-chemoradiation-therapy-for-pancreatic-cancer
#17
X Chen, D Schott, Y Song, D Li, W Hall, B Erickson, X Li
PURPOSE: In an effort of early assessment of treatment response, we investigate radiation induced changes in CT number histogram of GTV during the delivery of chemoradiation therapy (CRT) for pancreatic cancer. METHODS: Diagnostic-quality CT data acquired daily during routine CT-guided CRT using a CT-on-rails for 20 pancreatic head cancer patients were analyzed. All patients were treated with a radiation dose of 50.4 in 28 fractions. On each daily CT set, the contours of the pancreatic head and the spinal cord were delineated...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28047590/su-f-r-02-imaging-genomics-for-predicting-gbm-molecular-subclasses-and-survival
#18
F Mahmoudi, L Poisson, H Bagher-Ebadian, M Nazem-Zadeh, H Soltanian-Zadeh
PURPOSE: Glioblastoma (GBM) is the most common and fatal primary intracranial neoplasm. GBM is categorized into five sub-classes (classical, G-CIMP, mesenchymal, proneural and neural) that can only be determined by an invasive brain biopsy followed by RNA and DNA methylation profiling. The goal of this study is to develop imaging features extracted from conventional MRI scans and an ensemble-classification method as a potential noninvasive method to predict the five molecular sub-classes and 12-month survival status...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28047319/su-f-t-303-quantification-of-mlc-positioning-accuracy-in-vmat-delivery-of-head-and-neck-cancer-treatment
#19
X Li, F Yang
PURPOSE: Knowing MLC leaf positioning error over the course of treatment would be valuable for treatment planning, QA design, and patient safety. The objective of the current study was to quantify the MLC positioning accuracy for VMAT delivery of head and neck treatment plans. METHODS: A total of 837 MLC log files were collected from 14 head and neck cancer patients undergoing full arc VMAT treatment on one Varian Trilogy machine. The actual and planned leaf gaps were extracted from the retrieved MLC log files...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28046969/su-d-207b-04-morphological-features-of-mri-as-a-correlate-of-capsular-contracture-in-breast-cancer-patients-with-implant-based-reconstructions
#20
N Tyagi, E Sutton, M Hunt, A Apte, J Zhang, J Oh, J Mechalakos, B Mehrara, E Matros, A Ho
PURPOSE: Capsular contracture (CC) is a serious complication in patients receiving implant-based reconstruction for breast cancer. The goal of this study was to identify image-based correlates of CC using MRI imaging in breast cancer patients who received both MRI and clinical evaluation following reconstructive surgery. METHODS: We analyzed a retrospective dataset of 50 patients who had both a diagnostic MR and a plastic surgeon's evaluations of CC score (Baker's score) within a six month period following mastectomy and reconstructive surgery...
June 2016: Medical Physics
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