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Biomedical subjects

D Koutsouris

Publications and source records attributed to D Koutsouris.

At least 19 recordsLinked to original sources

Medical support system for continuation of care based on XML web technology.

In this paper, the implementation of an Internet-based telematic service for medical support is presented, which was developed and operated in pilot form within the INTRANET HEALTH CLINIC project--a 2-year project supported by the European Commission under the Health Telematics Programme. The aim of the application is to offer high quality care to users of health services over inexpensive communication pathways, using Internet-based, interactive communication tools, like remote access to medical records and transmission of multimedia information. The XML technology was employed to achieve customised views on patient data, according to the access rights of different user profiles. Strict security and access control policy were implemented to ensure secure transmission of medical data through the Internet. The system was designed to collaborate with existing clinical patient record systems and to be adjustable to different medical applications. Current implementations include the fields of Oncology, Lupus Erythrematosis, Obstetrics and Chronic Obstructive Pulmonary disease. The results of the pilot operation with oncological patients in Greece were encouraging, so that the refining of the system and its expansion to a large number of patients is already in progress.

Continuity of Patient Care↗

Effect of wavelet compression on data transmission in a multipurpose wireless telemedicine system.

We have developed a novel emergency telemedicine system which allows the transmission of physiological data (electrocardiogram, oximetry, blood pressure and temperature) and still images of the patient. The transmission is performed through wireless links using either GSM mobile phones or satellite. Because of the low bandwidth available through these links, data compression is required to allow realtime transmission of electrocardiographic (ECG) data. A new integrated design approach for an optimal zonal wavelet compression (OZWC) method was implemented for the ECG data. The performance of the mobile system with compressed ECG data segments was evaluated in terms of the percentage root-mean-square difference and visual inspection. The optimum wavelet algorithm achieved a maximum compression ratio of 18:1 with low distortion.

Algorithms↗

XML and the VITAL standard: the document-oriented approach for open telemedicine applications.

This paper describes an effort to create a common, document-oriented architecture for the interchange of medical data in healthcare telemedicine applications. Key components are: The VITAL standard specifying a common (medical device independent) representation of Vital Signs Information and the Extensible Markup Language (XML) specifying the document specifications form, an architecture that, in aggregate, define the semantics and structural constraints necessary for the exchange of vital signs and related medical data. The modelling and design technique for the described application has been the Unified Modelling Language (UML). The XMI (XML Metadata Interchange Format) of the Object Management Group (OMG) provided the meta-model for this application, for sharing objects using XML, via the transfer of the application's UML model to XML documents and DTDs.

Humans↗

An overview in healthcare information systems security.

The scope of this paper is to present the current needs and trends in the field of healthcare systems security. The approach applied within the described review was based on three major steps. The first step was to define the point and ways of penetration and integration of security services in current healthcare related applications addressing technical, organisational and legal/regulatory issues. The second step was to specify and evaluate common security technologies applied in healthcare information systems pointing out gaps and efficient solutions, whereas the third was to draw conclusions for the present conditions and identify the future trends of healthcare information security. A number of EU RTD Projects were selected, categorised, analysed and comparatively evaluated in terms of security. The technical focus was on key security technologies, like Public Key Infrastructures (PKIs) based on Trusted Third Parties (TTPs) in conjunction with other state-of-the-art security components (programming tools, data representation formats, security standards and protocols, security policies and risk assessment techniques). The experience gained within this review will provide valuable input for future security applications in the healthcare sector, solving existing problems and addressing real user needs.

Computer Security↗

Simulated generation of evoked potentials components using networks with distinct excitatory and inhibitory neurons.

Long latency evoked potentials (EP's) are electrical potentials related to brain information processing mechanisms. In this paper, three-layered neurophysiologically based artificial neural network model is presented whose neurons obey to Dale's law. The first two layers of the network can memorize and recall sparsely coded patterns, oscillating at biologically plausible frequencies. Excitatory low-pass filtering synapses, from the second to the third layer, create evoked current dipoles, when the network retrieves memories related to stimuli. Based on psychophysiological indications, simulated intracranial dipoles are straightforwardly transformed into long latency EP components such as N100 and P300 that match laboratory-measured scalp EP's.

Biomedical Engineering↗

Education and training in the MEDICOM system.

MEDICOM system is a world wide telematics application for electronic commerce of medical devices. It has been designed so as to provide the health care professionals with a central Internet access to up-to-date information about medical equipment from multiple manufacturers, in a particular easy and friendly way. Moreover, the Medicom system will serve the health care professionals' requirements for high-quality information about specific products in a form of multimedia presentations and that of a secure communication channel with the community of manufacturers, especially for post marketing surveillance. The system will provide the medical staff (physicians and technicians) with demonstrations of the operation procedures and the functioning of high-tech equipment in a form of virtual models. Moreover, through the medicom system the end users of medical devices can have access to on line libraries and participate in special newsgroups. This paper discusses the architectural structure of the MEDICOM system with emphasis to its educational and training functionality.

Commerce↗

Mobile Medical Data (MOMEDA)--a Personalized Medical Information System.

MOMEDA is a two-years project supported by the European Commission (Telematics Applications Programme of DGXIII--Health Care Sector). The main objectives of the project are the development of a compact personal information terminal for hospital and home care environments that could be used by patients and a demonstrator that allows the consulting physician to access electronic patient record data from outside the hospital, using a hand held companion device connected to GSM network. Special attention is paid to a Personalized Medical Information System (PMIS) which will allow patients to access customized disease-specific information material that will enable them to fully understand in a simple and constructive form what their medical problem is, what the planned procedures are, what lifestyle they should follow during and after their hospitalization, thus becoming more qualified partners in the recovery process. Considering the fact that in most cases informed and educated patients are usually satisfied patients when the treatment is finished, patient satisfaction can be also accomplished. The design considerations for the PMIS system are presented and the implementation is discussed.

Computer Security↗

Intranet health clinic: Web-based medical support services employing XML.

In this paper, the implementation of an Internet-based telematic service for medical support is presented, which operates in pilot form within the INTRANET HEALTH CLINIC project--a two-year project supported by the European Commission under the Health Telematics Programme. The aim of the application is to offer high quality care to users of health services over inexpensive communication pathways, using Internet-based, interactive communication tools, like remote access to medical records and transmission of multimedia information. The XML technology was employed to achieve customised views on patient data, according to the access rights of different users. Strict security and access control policy were implemented to ensure secure transmission of medical data through the Internet. The system is designed to collaborate with existing clinical patient record systems and to be adjustable to different medical applications. Current pilot implementations are under clinical evaluation and include oncological patients (Greece), Lupus Erythrematosis (Canada), Obstetrics (Belgium) and Chronic Obstructive Pulmonary disease (Spain).

Computer Communication Networks↗

Vital signs monitoring from home with open systems.

This study investigates the applicability of a novel codification scheme based on two healthcare informatics standards (namely the VITAL (ENV 13734) and DICOM Sup. 30 Waveform Interchange) in addressing the robust interchange of waveform and medical data in remote healthcare applications. To further address system validation and clinical acceptance issues, pilots were set-up between home-monitoring stations and a hospital-based telemedicine consultation center. The pilots focused in assessing applicability, technical feasibility and performance of the proposed codification scheme based on the two standards. This paper presents the system and services requirements as studied for a home-care application, the design goals for the preservation of security stature, the practical issues of validation and the results of integrating these codification schemes into a commercial patient connected device.

Computer Systems↗

A new method for measuring red blood cell aggregation using pattern recognition techniques on backscattered ultrasound Doppler signals.

In order to study the important phenomenon of aggregation of red blood cell in vitro, an original ultrasound Doppler in vitro technique has been designed and developed in our laboratory. In the experiments held with this new technique, erythrocyte aggregation was examined by adding dextrans of different molecular weights and concentrations for a wide range of hematocrit values. Consequently, a large data base of backscattered ultrasound Doppler signals is created. In these signals, various pattern recognition methods have been applied, mainly morphological and statistical ones. It results from the employed analysis that the envelope, energy and area characteristics of the obtained backscattered signals are quite good indicators of the degree of RBCs aggregation. In this way, we have been able to: (a) Establish a quantitative relation between the presence of various dextrans and the degree of aggregation. (b) Determine the distribution of the size of the formed aggregates in the various experimental solutions. (c) Obtain a most accurate relation between ultrasound backscattering and actual size of the corresponding observed aggregates.

Erythrocyte Aggregation↗

A novel emergency telemedicine system based on wireless communication technology--AMBULANCE.

Recent studies conclude that early and specialized prehospital management contributes to emergency case survival. We have developed a portable medical device that allows telediagnosis, long distance support, and teleconsultation of mobile healthcare providers by expert physicians. The device allows the transmission of vital biosignals and still images of the patient from the emergency site to the consultation site using the GSM mobile telephony network. The device can telematically "bring" an expert specialist doctor at the site of the medical emergency, allow him/her to evaluate patient data, and issue directions to the emergency personnel on treatment procedures until the patient is brought to be hospital. Legal reasons mandated the inclusion at the consultation site of a multimedia database able to store and manage the data collected by the system. The performance of the system has been validated in four different countries using a controlled medical protocol and a set of 100 patients per country treated has been collected and analyzed.

Emergency Medical Services↗

Design and development of a multimedia database for emergency telemedicine.

Recent studies conclude that early and specialised pre-hospital patient management contributes to emergency cases survival. Recent developments in telecommunication and medical informatics by means of telemedicine can be extremely useful to accomplish such tasks in a cost-effective manner. Along that direction, we have designed a portable device for emergency telemedicine. This device is able to telematically "bring" the expert doctor at the emergency site, have him perform an accurate diagnosis, and subsequently direct the Emergency Medical Technicians on how to treat the patient until he arrives to the hospital. The need for storing and archiving all data being interchanged during the telemedicine sessions is very crucial for clinical, legal and administrative purposes. For this, we have developed a multimedia database able to store and manage the data collected by the AMBULANCE system. The database was equipped with a user-friendly graphical interface to enable use from computer naive users. Furthermore, the database has the possibility to display, in an standard way, ECG's, X-ray, CT and MRI images. The application is password protected with a three-level hierarchy access for users with different privileges. The scope of this application is to enhance the capabilities of the doctor on duty for a more precise and prompt diagnosis. The application has the ability to store audio files related to each emergency case and still images of the scene. Finally, this database can become a useful multimedia tool which will work together with the AMBULANCE portable device, the HIS and the PACS of the hospital. The system has been validated in selected non-critical cases and proved to be functional and successful in enhancing the ability of the doctor's on duty for prompt and accurate diagnosis and specialised pre-hospital treatment.

Ambulances↗

Loading of intact rabbit erythrocytes with fluorophores and the enzyme pronase by means of electroporation.

The application of electric field pulses in cell suspensions is known to alter membrane integrity, resulting in increased membrane permeabilization. This field-induced membrane poration provides the means to load cells with a variety of external substances, useful for clinical applications. In this work, intact rabbit erythrocytes were successfully loaded with low molecular weight fluorescent probes and with the high molecular weight enzyme pronase, which has been shown to mimic the effects of insulin. Attachment of the enzyme onto the cell surface was also achieved by modifying the applied pulse parameters. Both applications were efficient and accompanied by high cell survival rates. In this way, biological carriers loaded with active substances were produced, offering the potentials for useful clinical applications, either for diagnostic or therapeutic purposes.

Animals↗

CT-based software for 3-D localization and reconstruction in stepping source brachytherapy.

This paper describes innovative software for catheter localization and three-dimensional (3-D) reconstruction in stepping source brachytherapy applications. Patient information is a set of computed tomography (CT) slices scanned during the implantation of brachytherapy catheters. Catheter geometry and patient anatomy are exported for use with dose calculation software modules. The errors produced by the system are also encouragingly low. Time saving was achieved, in terms of other traditional reconstruction techniques. Various automated procedures, 3-D graphics and a user-friendly GUI, have contributed to providing a powerful, comprehensive software tool, directly useable in the clinical practice.

Brachytherapy↗

An augmented reality system for health care provision via telematics support.

We are developing a prototype portable health care support device for Emergency Telemedicine. This device can telematically "bring" a specialist doctor at the site of a medical emergency, allow him to evaluate patient data and issue directions to the emergency personnel on treatment procedures until the patient is brought to hospital. The portable device is carried by a paramedic technician in "wearable" form, allowing the technician to perform his normal duties while communicating with the specialist at the hospital site. This augmented reality system allows for maximum utilisation of available resources and offers a complete, practical solution for increasing survival rates before and during the transportation of accident victims to hospital.

Emergency Medical Services↗

The CARDIO-LOGOS system for ECG training and diagnosis.

A new approach in ECG training is presented. The overall approach is based on a combination of the "page-turning architecture", the "reference model" and AI techniques. A thorough analysis of the training requirements in this field has been carried out; the results determined the educational scenarios and the associated evaluation sessions. The system (CARDIO-LOGOS) is intended to be used mainly by internal medicine physicians and general practitioners, as well as by medical students. The layered structure of the whole CBT application together with the advanced learning strategies and the interactive multimedia technology offer a flexible environment that encourages experimentation and supports individualised training for a wide variety of users.

Computer Simulation↗

Determination of RBC flow clogging via micropore filters.

Using a prototype system we determine the dynamic behaviour of the clogging effect of an erythrocyte suspension flow via micropore filters. The system functions as a simple electronic device and a characteristic curve of the change in height of the level of RBC suspension which flows through the filter versus time is plotted.

Erythrocytes↗