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https://www.readbyqxmd.com/read/28227983/3d-small-structure-detection-in-medical-image-using-texture-analysis
#1
Fei Gao, Min Zhang, Teresa Wu, Kevin M Bennett, Fei Gao, Min Zhang, Teresa Wu, Kevin M Bennett, Min Zhang, Teresa Wu, Fei Gao, Kevin M Bennett
Small structure segmentation from medical images is a challenging problem yet has important applications. Examples are labeling cell, lesion and glomeruli for disease diagnosis, just to name a few. Though extensive research has proposed various detectors for this type of problem, most are 2D detectors. Recently, we have developed a Hessian based 3D detector to segment small structures from medical images (e.g., MRI). In our detector, two 3D geometrical features: regional blobness and flatness, in conjunction with the intensity features are fully utilized to serve the segmentation purpose...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227982/analysis-of-the-sleep-eeg-in-the-complexity-domain
#2
Sara Mariani, Ana F T Borges, Teresa Henriques, Robert J Thomas, Samuel J Leistedt, Paul Linkowski, Jean-Pol Lanquart, Ary L Goldberger, Madalena D Costa, Sara Mariani, Ana F T Borges, Teresa Henriques, Robert J Thomas, Samuel J Leistedt, Paul Linkowski, Jean-Pol Lanquart, Ary L Goldberger, Madalena D Costa, Teresa Henriques, Robert J Thomas, Madalena D Costa, Samuel J Leistedt, Paul Linkowski, Ary L Goldberger, Jean-Pol Lanquart, Sara Mariani, Ana F T Borges
Conventional sleep analysis relies primarily on electroencephalogram (EEG) waveform features assessed in concert with eye movements, respiration and muscle tone. We explore a complementary "complexity domain" approach based on multiscale entropy (MSE) analysis of EEG signals and discuss its relationships to standard sleep analysis and to that based on electrocardiogram (ECG)-derived cardiopulmonary coupling (CPC). We observe a progressive decrease in complexity associated with decreased arousability, as measured by both conventional sleep scoring and CPC analysis...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227979/dispersion-entropy-for-the-analysis-of-resting-state-meg-regularity-in-alzheimer-s-disease
#3
Hamed Azami, Mostafa Rostaghi, Alberto Fernandez, Javier Escudero, Hamed Azami, Mostafa Rostaghi, Alberto Fernandez, Javier Escudero, Alberto Fernandez, Javier Escudero, Mostafa Rostaghi, Hamed Azami
Alzheimer's disease (AD) is a progressive degenerative brain disorder affecting memory, thinking, behaviour and emotion. It is the most common form of dementia and a big social problem in western societies. The analysis of brain activity may help to diagnose this disease. Changes in entropy methods have been reported useful in research studies to characterize AD. We have recently proposed dispersion entropy (DisEn) as a very fast and powerful tool to quantify the irregularity of time series. The aim of this paper is to evaluate the ability of DisEn, in comparison with fuzzy entropy (FuzEn), sample entropy (SampEn), and permutation entropy (PerEn), to discriminate 36 AD patients from 26 elderly control subjects using resting-state magnetoencephalogram (MEG) signals...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227964/cross-entropy-optimization-for-neuromodulation
#4
Harleen K Brar, Yunpeng Pan, Babak Mahmoudi, Evangelos A Theodorou, Harleen K Brar, Yunpeng Pan, Babak Mahmoudi, Evangelos A Theodorou, Yunpeng Pan, Harleen K Brar, Babak Mahmoudi, Evangelos A Theodorou
This study presents a reinforcement learning approach for the optimization of the proportional-integral gains of the feedback controller represented in a computational model of epilepsy. The chaotic oscillator model provides a feedback control systems view of the dynamics of an epileptic brain with an internal feedback controller representative of the natural seizure suppression mechanism within the brain circuitry. Normal and pathological brain activity is simulated in this model by adjusting the feedback gain values of the internal controller...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227959/localizing-seizure-onset-zone-by-convolutional-transfer-entropy-from-ieeg
#5
Kang Lin, Yueming Wang, Kedi Xu, Junming Zhu, Jianmin Zhang, Xiaoxiang Zheng, Kang Lin, Yueming Wang, Kedi Xu, Junming Zhu, Jianmin Zhang, Xiaoxiang Zheng, Xiaoxiang Zheng, Junming Zhu, Yueming Wang, Kedi Xu, Kang Lin, Jianmin Zhang
Automatic localization of the seizure onset zone (SOZ) is able to output an objective result and help clinical doctors greatly in epilepsy therapy. Transfer entropy is one of the most frequently used measures based on information theory to localize the SOZ. However, if only using transfer entropy to localize the SOZ, different results can be obtained during different periods, thus humans still need to identify which one is most reasonable. This paper proposes a new method to output only a few (e.g. 1 or 2) results along a long time slot...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227934/effect-of-embedding-dimension-on-complexity-measures-in-identifying-arrhythmia
#6
Radhagayathri K Udhayakumar, Chandan Karmakar, Peng Li, Marimuthu Palaniswami, Radhagayathri K Udhayakumar, Chandan Karmakar, Peng Li, Marimuthu Palaniswami, Marimuthu Palaniswami, Radhagayathri K U Udhayakumar, Peng Li, Chandan Karmakar
Entropy measures like Approximate entropy (ApEn) and Sample entropy (SampEn) are well established tools to analyze Heart Rate Variability (HRV) data. Critical parameters involved in these computations namely embedding dimension m and tolerance r are in most cases assumed to be 2 and 0.2*signal SD (standard devaition) respectively. Such assumptions do not work fairly across data sets and thus create misleading results in many cases. Problems with r have been addressed with the advent of newer entropy measures like Permutation entropy (PE), Fuzzy entropy (FuzzyEn) and Distribution entropy (DistEn) that simply eliminate, modify or replace r from calculations...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227932/influence-of-embedding-dimension-on-distribution-entropy-in-analyzing-heart-rate-variability
#7
Radhagayathri K Udhayakumar, Chandan Karmakar, Peng Li, Marimuthu Palaniswami, Radhagayathri K Udhayakumar, Chandan Karmakar, Peng Li, Marimuthu Palaniswami, Marimuthu Palaniswami, Radhagayathri K Udhayakumar, Peng Li, Chandan Karmakar
Distribution entropy (DistEn) is a recent measure of complexity that is used to analyze Heart Rate Variability (HRV) data. DistEn which is a function of data length N, number of bins M and embedding dimension m is known to be stable and consistent with respect to parameters N and M respectively. Also, (N, M) are known to have a combined effect in deciding performance of DistEn as a classification feature. But, all such analysis have mostly ignored the influence of the third parameter m on DistEn properties...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227901/identifying-montages-that-best-detect-the-electroencephalogram-power-spectrum-alteration-during-freezing-of-gait-in-parkinson-s-disease-patients
#8
Quynh Tran Ly, A M Ardi Handojoseno, Moran Gilat, Nghia Nguyen, Rifai Chai, Yvonne Tran, Simon J G Lewis, Hung T Nguyen, Quynh Tran Ly, A M Ardi Handojoseno, Moran Gilat, Nghia Nguyen, Rifai Chai, Yvonne Tran, Simon J G Lewis, Hung T Nguyen, Nghia Nguyen, A M Ardi Handojoseno, Moran Gilat, Hung T Nguyen, Yvonne Tran, Simon J G Lewis, Quynh Tran Ly, Rifai Chai
Our research team has previously used four Electroencephalography (EEG) leads to successfully detect and predict Freezing of Gait (FOG) in Parkinson's disease (PD). However, it remained to be determined whether these four sensor locations that were arbitrarily chosen based on their role in motor control are indeed the most optimal for FOG detection. The aim of this study was therefore to determine the most optimal location and combination of sensors to detect FOG amongst a 32-channel EEG montage using our EEG classification system...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227844/maximum-entropy-based-common-spatial-patterns-for-motor-imagery-classification
#9
Syed Salman Ali, Lei Zhang, Syed Salman Ali, Lei Zhang, Syed Salman Ali, Lei Zhang
The common spatial pattern (CSP) is extensively used to extract discriminative feature from raw Electroencephalography (EEG) signals for motor imagery classification. The CSP is a statistical signal processing technique, which relies on sample based covariance matrix estimation to give discriminative information from raw EEG signals. The sample based estimation of covariance matrix becomes a problem when the number of training samples is limited, which causes the performance of CSP based brain computer interface (BCI) to degrade significantly...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227756/synchronization-of-brain-activity-during-induction-of-propofol-anesthesia-comparison-of-methods
#10
Tarmo Lipping, Jaanika Saareleht, Elzbieta Olejarczyk, Eila Sonkajarvi, Tuomo Ylinen, Ville Jantti, Tarmo Lipping, Jaanika Saareleht, Elzbieta Olejarczyk, Eila Sonkajarvi, Tuomo Ylinen, Ville Jantti, Jaanika Saareleht, Ville Jantti, Eila Sonkajarvi, Tuomo Ylinen, Elzbieta Olejarczyk, Tarmo Lipping
Synchrony patterns between the EEG measured from the subthalamic nucleus and scalp are analyzed during induction of propofol anesthesia. Various methods such as Coherence, Phase Locking Value, Partial Directed Coherence, Mutual Information, and Transfer Entropy are applied. The results indicate that, in general, the synchrony patterns seen in the depth-scalp electrode pair are similar to those seen between two scalp electrodes of opposite hemispheres. A clear change of state is revealed at about 10 minutes before burst suppression; this event is revealed by linear (Coherence) as well as nonlinear (Phase Locking Value) and information theoretic (Mutual Information and Transfer Entropy) measures...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227594/fall-risk-factors-analysis-based-on-sample-entropy-of-plantar-kinematic-signal-during-stance-phase
#11
Shengyun Liang, Huiyu Jia, Zilong Li, Huiqi Li, Xing Gao, Zuchang Ma, Yingnan Ma, Guoru Zhao, Shengyun Liang, Huiyu Jia, Zilong Li, Huiqi Li, Xing Gao, Zuchang Ma, Yingnan Ma, Guoru Zhao, Shengyun Liang, Huiqi Li, Huiyu Jia, Xing Gao, Zuchang Ma, Guoru Zhao, Yingnan Ma, Zilong Li
Falls are a multi-causal phenomenon with a complex interaction. The aim of our research is to study the effect of multiple variables for potential risk of falls and construct an elderly fall risk assessment model based on demographics data and gait characteristics. A total of 101 subjects, whom belong to Malianwa Street, aged above 50 years old and participated in questionnaire survey. Participants were classified into three groups (high, medium and low risk group) according to the score of elderly fall risk assessment scale...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227520/cross-frequency-information-transfer-from-eeg-to-emg-in-grasping
#12
Winnie K Y So, Lingling Yang, Beth Jelfs, Qi She, Savio W H Wong, Joseph N Mak, Rosa H M Chan, Winnie K Y So, Lingling Yang, Beth Jelfs, Qi She, Savio W H Wong, Joseph N Mak, Rosa H M Chan, Rosa H M Chan, Beth Jelfs, Savio W H Wong, Lingling Yang, Qi She, Joseph N Mak, Winnie K Y So
This paper presents an investigation into the cortico-muscular relationship during a grasping task by evaluating the information transfer between EEG and EMG signals. Information transfer was computed via a non-linear model-free measure, transfer entropy (TE). To examine the cross-frequency interaction, TEs were computed after the times series were decomposed into various frequency ranges via wavelet transform. Our results demonstrate the capability of TE to capture the direct interaction between EEG and EMG...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227337/prediction-of-the-outcome-in-cardiac-arrest-patients-undergoing-hypothermia-using-eeg-wavelet-entropy
#13
Hana Moshirvaziri, Nima Ramezan-Arab, Shadnaz Asgari, Hana Moshirvaziri, Nima Ramezan-Arab, Shadnaz Asgari, Hana Moshirvaziri, Nima Ramezan-Arab, Shadnaz Asgari
Cardiac arrest (CA) is the leading cause of death in the United States. Induction of hypothermia has been found to improve the functional recovery of CA patients after resuscitation. However, there is no clear guideline for the clinicians yet to determine the prognosis of the CA when patients are treated with hypothermia. The present work aimed at the development of a prognostic marker for the CA patients undergoing hypothermia. A quantitative measure of the complexity of Electroencephalogram (EEG) signals, called wavelet sub-band entropy, was employed to predict the patients' outcomes...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227333/memd-enhanced-multivariate-fuzzy-entropy-for-the-evaluation-of-complexity-in-biomedical-signals
#14
Hamed Azami, Keith Smith, Javier Escudero, Hamed Azami, Keith Smith, Javier Escudero, Javier Escudero, Keith Smith, Hamed Azami
Multivariate multiscale entropy (mvMSE) has been proposed as a combination of the coarse-graining process and multivariate sample entropy (mvSE) to quantify the irregularity of multivariate signals. However, both the coarse-graining process and mvSE may not be reliable for short signals. Although the coarse-graining process can be replaced with multivariate empirical mode decomposition (MEMD), the relative instability of mvSE for short signals remains a problem. Here, we address this issue by proposing the multivariate fuzzy entropy (mvFE) with a new fuzzy membership function...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227313/detection-of-crackle-events-using-a-multi-feature-approach
#15
L Mendes, I M Vogiatzis, E Perantoni, E Kaimakamis, I Chouvarda, N Maglaveras, J Henriques, P Carvalho, R P Paiva, L Mendes, I M Vogiatzis, E Perantoni, E Kaimakamis, I Chouvarda, N Maglaveras, J Henriques, P Carvalho, R P Paiva, I Chouvarda, P Carvalho, L Mendes, E Perantoni, R P Paiva, J Henriques, I M Vogiatzis, N Maglaveras, E Kaimakamis
The automatic detection of adventitious lung sounds is a valuable tool to monitor respiratory diseases like chronic obstructive pulmonary disease. Crackles are adventitious and explosive respiratory sounds that are usually associated with the inflammation or infection of the small bronchi, bronchioles and alveoli. In this study a multi-feature approach is proposed for the detection of events, in the frame space, that contain one or more crackles. The performance of thirty-five features was tested. These features include thirty-one features usually used in the context of Music Information Retrieval, a wavelet based feature as well as the Teager energy and the entropy...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227192/acoustic-evaluation-of-pirfenidone-on-patients-with-combined-pulmonary-fibrosis-emphysema-syndrome
#16
Sonia Charleston-Villalobos, Norma Castaneda-Villa, Ramon Gonzalez-Camarena, M Mejia-Avila, H Mateos-Toledo, Tomas Aljama-Corrales, Sonia Charleston-Villalobos, Norma Castaneda-Villa, Ramon Gonzalez-Camarena, M Mejia-Avila, H Mateos-Toledo, Tomas Aljama-Corrales, Tomas Aljama-Corrales, Ramon Gonzalez-Camarena, Sonia Charleston-Villalobos, Norma Castaneda-Villa, M Mejia-Avila, H Mateos-Toledo
The combined pulmonary fibrosis emphysema syndrome (CPFES) overall has a poor prognosis with a 5-year survival of 35-80%. Consequently, to evaluate possible positive effects on patients of novel agents as pirfenidone is relevant. However, the efficacy of pirfenidone in CPFES patients is still not well-known. In this study we propose an alternative to evaluate the effects of pirfenidone treatment on CPFES patients via acoustic information. Quantitative analysis of discontinuous adventitious lung sounds (DLS), known as crackles, has been promising to detect and characterize diverse pulmonary pathologies...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227134/cardiovascular-interactions-assessed-via-conditional-joint-transfer-entropy-in-patients-developing-atrial-fibrillation-after-coronary-artery-bypass-graft-surgery
#17
Vlasta Bari, Marco Ranucci, Andrea Marchi, Beatrice De Maria, Valeria Pistuddi, Alberto Porta, Vlasta Bari, Marco Ranucci, Andrea Marchi, Beatrice De Maria, Valeria Pistuddi, Alberto Porta, Vlasta Bari, Andrea Marchi, Alberto Porta, Valeria Pistuddi, Beatrice De Maria, Marco Ranucci
Assigned the universe of knowledge Ω as composed by one target and two exogenous signals, the conditional joint transfer entropy (CJTE), assessing the amount of information jointly transferred from the two sources to the target that can be uniquely linked to one of the two sources, was found useful to study cardiovascular control. We propose the assessment of CJTE from systolic arterial pressure (SAP) and respiration (R) to heart period (HP) conditioned on R (CJTESAP, R→HP|R) along the baroreflex, and from HP and R to SAP conditioned on R (CJTEHP, R→SAP|R) along the feedforward mechanical pathway, in 134 patients undergoing coronary artery bypass graft surgery before (PRE) and after (POST) the induction of general anesthesia...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227133/comparison-between-k-nearest-neighbor-approaches-for-conditional-entropy-estimation-application-to-the-assessment-of-the-cardiac-control-in-amyotrophic-lateral-sclerosis-patients
#18
Alberto Porta, Beatrice De Maria, Vlasta Bari, Andrea Marchi, Kalliopi Marinou, Riccardo Sideri, Gabriele Mora, Laura Dalla Vecchia, Alberto Porta, Beatrice De Maria, Vlasta Bari, Andrea Marchi, Kalliopi Marinou, Riccardo Sideri, Gabriele Mora, Laura Dalla Vecchia, Kalliopi Marinou, Gabriele Mora, Alberto Porta, Laura Dalla Vecchia, Riccardo Sideri, Beatrice De Maria, Vlasta Bari, Andrea Marchi
The study evaluates the k-nearest-neighbor (KNN) strategy for the assessment of complexity of the cardiac neural control from spontaneous fluctuations of heart period (HP). Two different procedures were assessed: i) the KNN estimation of the conditional entropy (CE) proposed by Porta et al; ii) the KNN estimation of mutual information proposed by Kozachenko-Leonenko, refined by Kraskov-Stögbauer-Grassberger and here adapted for the CE estimation. The two procedures were compared over HP variability recordings obtained at rest in supine position and during head-up tilt (HUT) in amyotrophic lateral sclerosis patients and healthy subjects...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227119/clinical-viability-of-carotid-plaque-strain-estimation-using-b-mode-ultrasound-image-sequences
#19
Amir A Khan, Joseph C Hecker, Brajesh K Lal, Siddhartha Sikdar, Amir A Khan, Joseph C Hecker, Brajesh K Lal, Siddhartha Sikdar, Siddhartha Sikdar, Brajesh K Lal, Amir A Khan, Joseph C Hecker
It is estimated that approximately 30% of ischemic strokes are caused by rupture of plaque in the carotid artery. Development of techniques focusing on identifying plaques that are vulnerable to rupture is thus indispensable for stroke prevention. Recent studies have demonstrated that motion analysis of plaques from B-mode and RF ultrasound (US) image sequences can be used to estimate plaque strain. However, viability of these methods in a clinical setting, with variable acquisition protocols, has not been demonstrated yet...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227108/analysis-of-spontaneous-eeg-activity-in-alzheimer-s-disease-using-cross-sample-entropy-and-graph-theory
#20
Carlos Gomez, Jesus Poza, Javier Gomez-Pilar, Alejandro Bachiller, Celia Juan-Cruz, Miguel A Tola-Arribas, Alicia Carreres, Monica Cano, Roberto Hornero, Carlos Gomez, Jesus Poza, Javier Gomez-Pilar, Alejandro Bachiller, Celia Juan-Cruz, Miguel A Tola-Arribas, Alicia Carreres, Monica Cano, Roberto Hornero, Celia Juan-Cruz, Carlos Gomez, Alicia Carreres, Jesus Poza, Monica Cano, Roberto Hornero, Javier Gomez-Pilar, Alejandro Bachiller, Miguel A Tola-Arribas
The aim of this pilot study was to analyze spontaneous electroencephalography (EEG) activity in Alzheimer's disease (AD) by means of Cross-Sample Entropy (Cross-SampEn) and two local measures derived from graph theory: clustering coefficient (CC) and characteristic path length (PL). Five minutes of EEG activity were recorded from 37 patients with dementia due to AD and 29 elderly controls. Our results showed that Cross-SampEn values were lower in the AD group than in the control one for all the interactions among EEG channels...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
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