—In this paper, we present the design and development of a pervasive health system enabling self-... more —In this paper, we present the design and development of a pervasive health system enabling self-management of chronic patients during their everyday activities. The proposed system integrates patient health monitoring, status logging for capturing various problems or symptoms met, and social sharing of the recorded information within the patient's community, aiming to facilitate disease management. A prototype is implemented on a mobile device illustrating the feasibility and applicability of the presented work by adopting unobtrusive vital signs monitoring through a wearable multisensing device, a service-oriented architecture for handling communication issues, and popular microblogging services. Furthermore, a study has been conducted with 16 hyperten-sive patients, in order to investigate the user acceptance, the usefulness , and the virtue of the proposed system. The results show that the system is welcome by the chronic patients who are especially willing to share healthcare information, and is easy to learn and use, while its features have been overall regarded by the patients as helpful for their disease management and treatment.
Rehabilitation is important for patients with cardiovascular diseases (CVD) to improve health out... more Rehabilitation is important for patients with cardiovascular diseases (CVD) to improve health outcomes and quality of life. However, adherence to current exercise programmes in cardiac rehabilitation is limited. We present the design and development of a Decision Support System (DSS) for telerehabilitation, aiming to enhance exercise programmes for CVD patients through ensuring their safety, personalising the programme according to their needs and performance, and motivating them toward meeting their physical activity goals. The DSS processes data originated from a Microsoft Kinect camera, a blood pressure monitor, a heart rate sensor and questionnaires, in order to generate a highly individualised exercise programme and improve patient adherence. Initial results within the EU-funded PATHway project show the potential of our approach.
Objective: The objective of this study is the development and evaluation of efficient neurophysio... more Objective: The objective of this study is the development and evaluation of efficient neurophysiological signal statistics, which may assess the driver's alertness level and serve as potential indicators of sleepiness in the design of an on-board countermeasure system. Methods: Multichannel EEG, EOG, EMG, and ECG were recorded from sleep-deprived subjects exposed to real field driving conditions. A number of severe driving errors occurred during the experiments. The analysis was performed in two main dimensions: the mac-roscopic analysis that estimates the ongoing temporal evolution of physiological measurements during the driving task, and the microscopic event analysis that focuses on the physiological measurements' alterations just before, during, and after the driving errors. Two independent neurophysiologists visually interpreted the measurements. The EEG data were analyzed by using both linear and non-linear analysis tools. Results: We observed the occurrence of brief paroxysmal bursts of alpha activity and an increased synchrony among EEG channels before the driving errors. The alpha relative band ratio (RBR) significantly increased, and the Cross Approximate Entropy that quantifies the synchrony among channels also significantly decreased before the driving errors. Quantitative EEG analysis revealed significant variations of RBR by driving time in the frequency bands of delta, alpha, beta, and gamma. Most of the estimated EEG statistics, such as the Shannon Entropy, Kullback–Leibler Entropy, Coherence, and Cross-Approximate Entropy, were significantly affected by driving time. We also observed an alteration of eyes blinking duration by increased driving time and a significant increase of eye blinks' number and duration before driving errors. Conclusions: EEG and EOG are promising neurophysiological indicators of driver sleepiness and have the potential of monitoring sleepi-ness in occupational settings incorporated in a sleepiness countermeasure device. Significance: The occurrence of brief paroxysmal bursts of alpha activity before severe driving errors is described in detail for the first time. Clear evidence is presented that eye-blinking statistics are sensitive to the driver's sleepiness and should be considered in the design of an efficient and driver-friendly sleepiness detection countermeasure device.
In the context of an IST European project with acronym PANACEIA-ITV, a home care service provisio... more In the context of an IST European project with acronym PANACEIA-ITV, a home care service provisioning system is described, based on interactive TV technology. The purpose of PANACEIA-ITV is to facilitate essential lifestyle changes and to promote compliance with scientifically sound self-care recommendations, through the application of interactive digital television for family health maintenance. The means to achieve these goals are based on technological, health services and business models. PANACEIA-ITV is looking for communication of monitoring micro-devices with I-TV set-top-boxes using infrared technology, and embodiment of analogous H/W and S/W in the I-TV set-top-boxes. Intelligent agents are used to regulate data flow, user queries as well as service provisions from and to the household through the satellite digital platform, the portal and the back-end decision support mechanisms, using predominantly the Active Service Provision (ASP) model. Moreover, interactive digital TV...
—In this paper, a multiagent system (MAS) is presented, aiming to enhance monitoring, surveillanc... more —In this paper, a multiagent system (MAS) is presented, aiming to enhance monitoring, surveillance, and educational services of a generic medical contact center (MCC) for chronic disease management. In such a home-care scenario, a persistent need arises for efficiently monitoring the patient contacts and the MCC's functionality, in order to effectively manage and interpret the large volume of medical data collected during the patient sessions with the system, and to assess the use of MCC resources. Software agents were adopted to provide the means to accomplish such real-time information-processing tasks, due to their autonomous, reactive and/or proactive nature, and their effectiveness in dynamic environments by incorporating coordination strategies. Specifically, the objective of the MAS is to monitor the MCC environment, detect important cases, and inform the healthcare and administrative personnel via alert messages, notifications, recommendations, and reports, prompting them for actions. The main aim of this paper is to present the overall design and implementation of a proposed MAS, emphasizing its functional model and architecture, as well as on the agent interactions and the knowledge-sharing mechanism incorporated, in the context of a generic MCC. Index Terms—Chronic disease management, home-care system, knowledge sharing, medical contact center (MCC), monitoring and administration, multiagent system (MAS), telemedicine.
IEEE Transactions on Information Technology in Biomedicine, 2000
The ongoing efforts toward continuity of care and the recent advances in information and communic... more The ongoing efforts toward continuity of care and the recent advances in information and communication technologies have led to a number of successful personal health systems for the management of chronic care. These systems are mostly focused on monitoring efficiently the patient's medical status at home. This paper aims at extending home care services delivery by introducing a novel framework for monitoring the patient's condition and safety with respect to the medication treatment administered. For this purpose, considering a body area network (BAN) with advanced sensors and a mobile base unit as the central communication hub from the one side, and the clinical environment from the other side, an architecture was developed, offering monitoring patterns definition for the detection of possible adverse drug events and the assessment of medication response, supported by mechanisms enabling bidirectional communication between the BAN and the clinical site. Particular emphasis was given on communication and information flow aspects that have been addressed by defining/adopting appropriate formal information structures as well as the service-oriented architecture paradigm. The proposed framework is illustrated via an application scenario concerning hypertension management.
The aim of the present paper, is the estimation of the distance between an electrode used as a re... more The aim of the present paper, is the estimation of the distance between an electrode used as a recording site of the extracellular potential field and a surviving myocardial bundle. The importance of the reliable solution of this problem lies among others in controlling ablation. For our purposes one-dimensional propagation is considered and current sources are activated along a cable simulating the propagating waves with constant velocity. Different models of current sources are explored. By use of these models, the corresponding functions expressing extracellular potentials are calculated, using the volume conductor equation. This way, extracellular potentials are modeled as parametric functions of longitudinal distance, while perpendicular distance, current source strength, and other factors related to the propagated wave are parameters of the functions. Simulated annealing is applied for model parameter estimation and appropriate Time Domain and Wavelet Domain cost functions are investigated. Different combinations of model and cost function are evaluated regarding the accuracy of distance estimation. A continuous source model function with a wavelet cost function was found to be the most accurate combination. The accuracy of distance estimation is related to the selected source model and to the actual distance of recording in a nonmonotonic way.
The management of the health status of chronically ill patients eg diabetic, asthma or congestive... more The management of the health status of chronically ill patients eg diabetic, asthma or congestive heart failure patients, can be accomplished more effectively by emphasizing prevention and advice rather than hospital treatment. By using today's personal communications solutions as a technological platform, daily monitoring of fundamental vital parameters can become an indispensable tool for continuous health monitoring, education, management and assessment. The huge amount of medical data to be processed ...
Foundations of Augmented Cognition. Neuroergonomics and Operational Neuroscience, 2009
Abstract. The main objective of this work is the study of EEG signals in order to investigate sle... more Abstract. The main objective of this work is the study of EEG signals in order to investigate sleepiness induced from drug administration for insomnia and sleep deprivation. Data used in this work were obtained from real experiments in FORENAP, France and in CERTH, Thessaloniki, Greece. The features under consideration are Power Spectrum in certain frequency areas, alpha slow-wave index (ASI) and Fractal Dimension (FD) for placebo and verum subjects. Studying these features in the above groups, we found that sleepiness ...
2014 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2014
A statistical analysis of the separability of EEG A-phases, with respect to basal activity, is pr... more A statistical analysis of the separability of EEG A-phases, with respect to basal activity, is presented in this study. A-phases are short central events that build up the Cyclic Alternating Pattern (CAP) during sleep. The CAP is a brain phenomenon which is thought to be related to the construction, destruction and instability of sleep stages dynamics. From the EEG signals, segments obtained around the onset and offset of the A-phases were used to evaluate the separability between A-phases and basal sleep stage oscillations. In addition, a classifier was trained to separate the different A-phase types (A1, A2 and A3). Temporal, energy and complexity measures were used as descriptors for the classifier. The results show a percentage of separation between onset and preceding basal oscillations higher than 85 % for all A-phases types. For Offset separation from following baseline, the accuracy is higher than 80 % but specificity is around 75%. Concerning to A-phase type separation, A1-phase and A3-phase are well separated with accuracy higher than 80, while A1 and A2-phases show a separation lower than 50%. These results encourage the design of automatic classifiers for Onset detection and for separating among A-phases type A1 and A3. On the other hand, the A-phase Offsets present a smooth transition towards the basal sleep stage oscillations, and A2-phases are very similar to A1-phases, suggesting that a high uncertainty may exist during CAP annotation.
—In this paper, we present the design and development of a pervasive health system enabling self-... more —In this paper, we present the design and development of a pervasive health system enabling self-management of chronic patients during their everyday activities. The proposed system integrates patient health monitoring, status logging for capturing various problems or symptoms met, and social sharing of the recorded information within the patient's community, aiming to facilitate disease management. A prototype is implemented on a mobile device illustrating the feasibility and applicability of the presented work by adopting unobtrusive vital signs monitoring through a wearable multisensing device, a service-oriented architecture for handling communication issues, and popular microblogging services. Furthermore, a study has been conducted with 16 hyperten-sive patients, in order to investigate the user acceptance, the usefulness , and the virtue of the proposed system. The results show that the system is welcome by the chronic patients who are especially willing to share healthcare information, and is easy to learn and use, while its features have been overall regarded by the patients as helpful for their disease management and treatment.
Rehabilitation is important for patients with cardiovascular diseases (CVD) to improve health out... more Rehabilitation is important for patients with cardiovascular diseases (CVD) to improve health outcomes and quality of life. However, adherence to current exercise programmes in cardiac rehabilitation is limited. We present the design and development of a Decision Support System (DSS) for telerehabilitation, aiming to enhance exercise programmes for CVD patients through ensuring their safety, personalising the programme according to their needs and performance, and motivating them toward meeting their physical activity goals. The DSS processes data originated from a Microsoft Kinect camera, a blood pressure monitor, a heart rate sensor and questionnaires, in order to generate a highly individualised exercise programme and improve patient adherence. Initial results within the EU-funded PATHway project show the potential of our approach.
Objective: The objective of this study is the development and evaluation of efficient neurophysio... more Objective: The objective of this study is the development and evaluation of efficient neurophysiological signal statistics, which may assess the driver's alertness level and serve as potential indicators of sleepiness in the design of an on-board countermeasure system. Methods: Multichannel EEG, EOG, EMG, and ECG were recorded from sleep-deprived subjects exposed to real field driving conditions. A number of severe driving errors occurred during the experiments. The analysis was performed in two main dimensions: the mac-roscopic analysis that estimates the ongoing temporal evolution of physiological measurements during the driving task, and the microscopic event analysis that focuses on the physiological measurements' alterations just before, during, and after the driving errors. Two independent neurophysiologists visually interpreted the measurements. The EEG data were analyzed by using both linear and non-linear analysis tools. Results: We observed the occurrence of brief paroxysmal bursts of alpha activity and an increased synchrony among EEG channels before the driving errors. The alpha relative band ratio (RBR) significantly increased, and the Cross Approximate Entropy that quantifies the synchrony among channels also significantly decreased before the driving errors. Quantitative EEG analysis revealed significant variations of RBR by driving time in the frequency bands of delta, alpha, beta, and gamma. Most of the estimated EEG statistics, such as the Shannon Entropy, Kullback–Leibler Entropy, Coherence, and Cross-Approximate Entropy, were significantly affected by driving time. We also observed an alteration of eyes blinking duration by increased driving time and a significant increase of eye blinks' number and duration before driving errors. Conclusions: EEG and EOG are promising neurophysiological indicators of driver sleepiness and have the potential of monitoring sleepi-ness in occupational settings incorporated in a sleepiness countermeasure device. Significance: The occurrence of brief paroxysmal bursts of alpha activity before severe driving errors is described in detail for the first time. Clear evidence is presented that eye-blinking statistics are sensitive to the driver's sleepiness and should be considered in the design of an efficient and driver-friendly sleepiness detection countermeasure device.
In the context of an IST European project with acronym PANACEIA-ITV, a home care service provisio... more In the context of an IST European project with acronym PANACEIA-ITV, a home care service provisioning system is described, based on interactive TV technology. The purpose of PANACEIA-ITV is to facilitate essential lifestyle changes and to promote compliance with scientifically sound self-care recommendations, through the application of interactive digital television for family health maintenance. The means to achieve these goals are based on technological, health services and business models. PANACEIA-ITV is looking for communication of monitoring micro-devices with I-TV set-top-boxes using infrared technology, and embodiment of analogous H/W and S/W in the I-TV set-top-boxes. Intelligent agents are used to regulate data flow, user queries as well as service provisions from and to the household through the satellite digital platform, the portal and the back-end decision support mechanisms, using predominantly the Active Service Provision (ASP) model. Moreover, interactive digital TV...
—In this paper, a multiagent system (MAS) is presented, aiming to enhance monitoring, surveillanc... more —In this paper, a multiagent system (MAS) is presented, aiming to enhance monitoring, surveillance, and educational services of a generic medical contact center (MCC) for chronic disease management. In such a home-care scenario, a persistent need arises for efficiently monitoring the patient contacts and the MCC's functionality, in order to effectively manage and interpret the large volume of medical data collected during the patient sessions with the system, and to assess the use of MCC resources. Software agents were adopted to provide the means to accomplish such real-time information-processing tasks, due to their autonomous, reactive and/or proactive nature, and their effectiveness in dynamic environments by incorporating coordination strategies. Specifically, the objective of the MAS is to monitor the MCC environment, detect important cases, and inform the healthcare and administrative personnel via alert messages, notifications, recommendations, and reports, prompting them for actions. The main aim of this paper is to present the overall design and implementation of a proposed MAS, emphasizing its functional model and architecture, as well as on the agent interactions and the knowledge-sharing mechanism incorporated, in the context of a generic MCC. Index Terms—Chronic disease management, home-care system, knowledge sharing, medical contact center (MCC), monitoring and administration, multiagent system (MAS), telemedicine.
IEEE Transactions on Information Technology in Biomedicine, 2000
The ongoing efforts toward continuity of care and the recent advances in information and communic... more The ongoing efforts toward continuity of care and the recent advances in information and communication technologies have led to a number of successful personal health systems for the management of chronic care. These systems are mostly focused on monitoring efficiently the patient's medical status at home. This paper aims at extending home care services delivery by introducing a novel framework for monitoring the patient's condition and safety with respect to the medication treatment administered. For this purpose, considering a body area network (BAN) with advanced sensors and a mobile base unit as the central communication hub from the one side, and the clinical environment from the other side, an architecture was developed, offering monitoring patterns definition for the detection of possible adverse drug events and the assessment of medication response, supported by mechanisms enabling bidirectional communication between the BAN and the clinical site. Particular emphasis was given on communication and information flow aspects that have been addressed by defining/adopting appropriate formal information structures as well as the service-oriented architecture paradigm. The proposed framework is illustrated via an application scenario concerning hypertension management.
The aim of the present paper, is the estimation of the distance between an electrode used as a re... more The aim of the present paper, is the estimation of the distance between an electrode used as a recording site of the extracellular potential field and a surviving myocardial bundle. The importance of the reliable solution of this problem lies among others in controlling ablation. For our purposes one-dimensional propagation is considered and current sources are activated along a cable simulating the propagating waves with constant velocity. Different models of current sources are explored. By use of these models, the corresponding functions expressing extracellular potentials are calculated, using the volume conductor equation. This way, extracellular potentials are modeled as parametric functions of longitudinal distance, while perpendicular distance, current source strength, and other factors related to the propagated wave are parameters of the functions. Simulated annealing is applied for model parameter estimation and appropriate Time Domain and Wavelet Domain cost functions are investigated. Different combinations of model and cost function are evaluated regarding the accuracy of distance estimation. A continuous source model function with a wavelet cost function was found to be the most accurate combination. The accuracy of distance estimation is related to the selected source model and to the actual distance of recording in a nonmonotonic way.
The management of the health status of chronically ill patients eg diabetic, asthma or congestive... more The management of the health status of chronically ill patients eg diabetic, asthma or congestive heart failure patients, can be accomplished more effectively by emphasizing prevention and advice rather than hospital treatment. By using today's personal communications solutions as a technological platform, daily monitoring of fundamental vital parameters can become an indispensable tool for continuous health monitoring, education, management and assessment. The huge amount of medical data to be processed ...
Foundations of Augmented Cognition. Neuroergonomics and Operational Neuroscience, 2009
Abstract. The main objective of this work is the study of EEG signals in order to investigate sle... more Abstract. The main objective of this work is the study of EEG signals in order to investigate sleepiness induced from drug administration for insomnia and sleep deprivation. Data used in this work were obtained from real experiments in FORENAP, France and in CERTH, Thessaloniki, Greece. The features under consideration are Power Spectrum in certain frequency areas, alpha slow-wave index (ASI) and Fractal Dimension (FD) for placebo and verum subjects. Studying these features in the above groups, we found that sleepiness ...
2014 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2014
A statistical analysis of the separability of EEG A-phases, with respect to basal activity, is pr... more A statistical analysis of the separability of EEG A-phases, with respect to basal activity, is presented in this study. A-phases are short central events that build up the Cyclic Alternating Pattern (CAP) during sleep. The CAP is a brain phenomenon which is thought to be related to the construction, destruction and instability of sleep stages dynamics. From the EEG signals, segments obtained around the onset and offset of the A-phases were used to evaluate the separability between A-phases and basal sleep stage oscillations. In addition, a classifier was trained to separate the different A-phase types (A1, A2 and A3). Temporal, energy and complexity measures were used as descriptors for the classifier. The results show a percentage of separation between onset and preceding basal oscillations higher than 85 % for all A-phases types. For Offset separation from following baseline, the accuracy is higher than 80 % but specificity is around 75%. Concerning to A-phase type separation, A1-phase and A3-phase are well separated with accuracy higher than 80, while A1 and A2-phases show a separation lower than 50%. These results encourage the design of automatic classifiers for Onset detection and for separating among A-phases type A1 and A3. On the other hand, the A-phase Offsets present a smooth transition towards the basal sleep stage oscillations, and A2-phases are very similar to A1-phases, suggesting that a high uncertainty may exist during CAP annotation.
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Papers by I. Chouvarda